# electronic lead screw



## greenail

I'm wondering what is state of the art for electronic lead screws these days and if anyone has advise based on implementing on on an import lathe?


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## markba633csi

Check youtube I believe a couple of guys have done it with arduino


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## JimDawson

The options are almost endless.  What exactly are you looking to do?


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## greenail

JimDawson said:


> The options are almost endless.  What exactly are you looking to do?



I'm wondering what hardware software combination to use.  the original ELS project seems a bit long in the tooth.  There are 3 or 4 on github and a Russian lead screw design.  

I "need" a 1/2"-12 left hand thread.  My lathe has no reverse so i'm thinking it would be just about as hard to do the electronic lead screw as it would be to add the reverse.  I'd also need to make a thread dial. Changing the gear on that thing set is no picnic either.


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## markba633csi

You can cut a left handed thread by simply reversing the carriage travel-  and you would need the gearing to cut 12 tpi
mark


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## JimDawson

It is really a very short distance from ELS to full on CNC and the CNC may actually be easier and cheaper to accomplish due to the availability of various kits.  The total cost could run from <$500 to as much as you want to spend.

If you want to keep full manual capability then it gets a bit more complicated, but not a show stopper.  The only addition required is backlash control on the carriage, and a couple of relays or switches to disconnect the stepper motors from the drives.  I was going to do this to my lathe but then I bought a CNC lathe and dropped that project.


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## greenail

Jim, do you ever find yourself wanting to have a manual lathe again?  I suppose the only thing stopping me is that having to do CAM for everything is a barrier to getting stuff done sometimes.  I have a cnc mill and a manual mill.  I kinda don't want to convert the manual mill since it is convenient and quicker for many things.


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## JimDawson

I still have my manual lathe, I didn't sell it when I bought the CNC.  I would really miss it if I didn't have it.  They are really 2 completely different machines with different purposes.  I have thought about adding CNC capability to the manual lathe, but keeping full manual operation with an instant change over.  I have all of the parts on the shelf to do it, but really have not had a need to do it.

My knee mill is almost instantly convertible between full manual, 2, 3, or 4 axis CNC.  Many times I use a combination of operating modes on a single job.


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## Dabbler

There's a nice ELS from Germany that they call an Electronic Lead Screw - Stefan Gotteseinter did a review of it on his youtube channel.  They will have a complete English manual available early this year. It leaves manual operation untouched and is DIY for the home machinist.


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## JimDawson

If you have not already read it, you might take a look at this thread https://www.hobby-machinist.com/threads/logan-model-200-servo-threading.64192/#post-531915


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## GreatOldOne

He’s up to video 6, where he’s been doing test cuts with the prototype.


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## greenail

My divorce got in the way of my attempt to implement an ELS but I recently saw a deal on mini lathe and ended up starting a CNC conversion with centroid which cut it's first chips last night!

I've watched clough42's videos.  I wish he had picked a more common and cheaper controller.  An esp32 is around $4 and an stm32 is about $1.5.  Both should be able to do the work.  The nice thing about the esp32 is that it has 2 cores and you can have one core handle monitoring the button inputs and the display while the other stays focused on spindle sync.  I also wonder if he is going to power the cross slide or if he is just going to leave it setup to sync the screw.  Adding cross slide feeding and feeding back to the start position saves a ton of cranking.

 My attempts used an esp32 which has plenty of processing power to synch the spindle.  I also attempted to set my implementation up to allow you to cut both ways but the backlash in my lead screw made this not possible.  I may dig back into it at some point but now that I have centroid to learn it may be a while.

If you implement an ELS you are really about 5 steps away from a full CNC implementation.  The thing that pushed me towards ELS was keeping manual control.  The ideal world has the full CNC conversion but allows for a really good manual control scheme.  I was thinking that some force feedback control wheels would be a very nice way to manually drive a converted lathe and maybe is a better project overall to work on.  I wish grbl's jog interface didn't suck so much, there are a few forks that implement spindle sync and bart dring's esp32 port is very nice.


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## kb58

greenail said:


> I've watched clough42's videos.  I wish he had picked a more common and cheaper controller.  An esp32 is around $4 and an stm32 is about $1.5.


The controller board is maybe another $20, roughly 15% of the total. Does that make it a no-go?


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## greenail

answer a: I have a few spares of the other MCU's so it would be easy to test if he chose something I already had on hand.

answer b:  I think you could get away with a non-hybrid stepper at a much cheaper cost.  the hybrid will give a much better torque curve and that really helps if you are trying to thread at a high speed.

answer c:  at $250 you are pretty close to a centroid or linux cnc setup.  The utility of a full CNC lathe setup is questionable for the hobbyist.

answer d: I think engineering the costs down as low as possible would make it more approachable to small lathe owners and the more prevalent the MCU is the more people could contribute.  I also think a fully canned threading cycle like the Russian ELS has would be fairly easy to do and would be worth the effort.  

All in all I wish the CNC community was a bit more open source oriented in general.  RepRap did a ton for 3d printing and I think there is still tons of room for the CNC hobbyist community.


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## ttabbal

I'm actually waiting for parts to give it a go on my PM1127. I ordered a larger stepper, not the hybrid. He mentioned testing both successfully, and I don't need the higher speeds. I suspect the stepper is overkill, but it wasn't that much more expensive than the smaller ones. I ordered a couple of belt and gear options, and the lathe has a gearbox for rough adjustment. 

While I have ESPs and other micros around, the cost of the MCU wasn't an issue. I know that it works and it looks like it has plenty of headroom. The MCU has a free IDE that is cross platform. Not quite as easy to pick up as Arduino, but it doesn't look difficult to work with. 

I know it's not much further to go full CNC, but I've been wanting to do at least the feeds this way for a while, and threading needs almost the same setup. That's enough for me, having a lathe has taught me that I always want a manual lathe around. CNC might be interesting on a second lathe in the future if I use my CNC router enough.


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## GreatOldOne

ttabbal said:


> I'm actually waiting for parts to give it a go



Me too. They all seem to be on the same slow boat from China though. Probably not the launchpad though. That’s coming from Digi-Key “UK”, which probably means the US but without the import duties...


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## ttabbal

I got parts in, now I need time.  I have a couple of things in the way before I can start installing things on the lathe. I did wire up everything to bench test and it looks good. 

I had some issues with the stepper setup I initially got. I found that they have a resonance point that causes what looks like missed steps. I think it would work with a digital controller, but I just got the same hybrid servo he used. 

Looking at the GT2 pulleys, it looks like the center is pressed in. Kind of annoying, as I need to cut a keyway in one. I think I'll also need to cut off the protruding bit with the set screws to fit the change gear axles on the lathe. I guess I could also press it out and replace it with my own.


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## GreatOldOne

Let the games commence!


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## Briney Eye

GreatOldOne said:


> Let the games commence!
> View attachment 303235


I’ll be interested to see how the Launchpad works for you. I used an Arduino Mega and pretty much the same parts you have, and have it working quite well but keep thinking up “one more” improvement. I suppose I should start participating in this thread and put up what I’ve done.


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## GreatOldOne

For those of you attempting the Clough42 build, these might be of help. My LED&KEY module had different hole spacing to his, so 8 ended up remixing his 3d printed parts to fit my board.









						Modified Clough42 ELS Panel by GreatOldOne
					

Remixed lid and spacer for the ELS project, as the LED&KEY TM1638 module I purchased from eBay had different hole spacing. Also the LEDs along the top are too close to the 7 segments to allow the top mounting holes to align with the spacer. These parts fit this...




					www.thingiverse.com


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## kb58

I'm building a Clough42 ELS for my Takisawa TSL-800.


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## Qtron

Dabbler said:


> There's a nice ELS from Germany that they call an Electronic Lead Screw - Stefan Gotteseinter did a review of it on his youtube channel.  They will have a complete English manual available early this year. It leaves manual operation untouched and is DIY for the home machinist.


found his site - nothing re ELS there! Searched Youtube under his name - couldn't find it. Are U referring to the expensive but slick Rocketronics.de ELS4?


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## Qtron

Briney Eye said:


> I’ll be interested to see how the Launchpad works for you. I used an Arduino Mega and pretty much the same parts you have, and have it working quite well but keep thinking up “one more” improvement. I suppose I should start participating in this thread and put up what I’ve done.


Am new to this forum, found this page & joined.. Am trying to find Jon Bryan, & more details other than the youtube clips re his amazing touchscreen ELS,
Can anyone assist please? (I am very keen to load the f/w into a Arduino Mega & test it, but need much more detail first, like backlash compensation, electronic gearbox steps, range, etc).


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## Dabbler

yes, I'm referring to the 'rocketronics' ELS.  I forgot their name (sorry)  The new one does circles and elipses, as well as tapers.  very nice...


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## Qtron

Thanks Dabbler Admin., converting EU to Oz $ plus freight, might as well use Mach3! But yes its slick as, best bit is X axis motorised.
ELS4 Pro even slicker / dearer, when released.
Jon Bryan's also very nice but no X axis drive.
I am hoping to rotate spindle slowly as well for cutting long curves, so an electronic indexer, married into Z feed, all as a standalone, for those oldies who cant use mach3 or PC's, with stored settings,memory. Probably too hard..


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## Briney Eye

Qtron said:


> Am new to this forum, found this page & joined.. Am trying to find Jon Bryan, & more details other than the youtube clips re his amazing touchscreen ELS,
> Can anyone assist please? (I am very keen to load the f/w into a Arduino Mega & test it, but need much more detail first, like backlash compensation, electronic gearbox steps, range, etc).


You found me.  I don't have any backlash compensation because it's not CNC, just a programmable "gearbox".  The number of pitch selections is arbitrary.  I've implemented every pitch that I could find in online pictures of lathes, and every tap available from McMaster-Carr.  I stopped short of having an arbitrary programmable option, but it would be possible.  I did limit it to 4tpi just because I have a small lathe.  That's getting to be some serious depth of cut, and I have already noticed some "hiccups" cutting an 8tpi Acme thread in 1144.  I'm waiting for more timing pulleys and belts so that I can gear it down from the current 4:1 ratio between the stepper and the screw.  I'm planning to test it at 5-, 6- and 8-to-1.

I still have more to do.  The touch screen is great for a lot of things, but on-the-fly feed direction control needed something more tactile, so I've added a toggle switch mounted in front of the headstock.  I quickly programmed it to control the direction, but have to add jogging support still.  I just got sidetracked by actually making some things.

I think it would be cool to do cut knurling, so I'm also thinking of adding support for multi-start threads, but that's a ways off yet.  I've only used half the RAM on the Mega so far, so there's still room to squeeze more features in .  I promise to make at least a basic version of the code available at some point when I'm satisfied with it.

-Jon


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## matthewsx

Qtron said:


> Thanks Dabbler Admin., converting EU to Oz $ plus freight, might as well use Mach3! But yes its slick as, best bit is X axis motorised.
> ELS4 Pro even slicker / dearer, when released.
> Jon Bryan's also very nice but no X axis drive.
> I am hoping to rotate spindle slowly as well for cutting long curves, so an electronic indexer, married into Z feed, all as a standalone, for those oldies who cant use mach3 or PC's, with stored settings,memory. Probably too hard..



Yes, a bit of a learning curve here but not sure it's more than doing an ELS.






						LinuxCNC
					

LinuxCNC: an open source CNC machine controller. It can drive milling machines, lathes, 3d printers, laser cutters, plasma cutters, robot arms, hexapods, and more.




					linuxcnc.org
				




Cheers,

John


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## Dabbler

The issue for me isn't just learning Mach3.  there's the entire toolchain to learn.  I programmed at all levels for 40 years, and -for me-  those days are over.  So I want a nice, pre-programmed solution that will up my game without retooling my brain for Fusion360, mach 3, dealing with feeds/speeds and other minor annoyances of CNC.  The ELS feels more like what I do manually, but reducing the operator-error possibilities.

I am following the various ELS threads on youtube as well as here.  It may be I can home-brew my own, but right now I'm leaning toward Rocketronics ELS in their largest size (My target lathe is 15" LrBlond).


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## matthewsx

Dabbler said:


> The issue for me isn't just learning Mach3.  there's the entire toolchain to learn.  I programmed at all levels for 40 years, and -for me-  those days are over.  So I want a nice, pre-programmed solution that will up my game without retooling my brain for Fusion360, mach 3, dealing with feeds/speeds and other minor annoyances of CNC.  The ELS feels more like what I do manually, but reducing the operator-error possibilities.
> 
> I am following the various ELS threads on youtube as well as here.  It may be I can home-brew my own, but right now I'm leaning toward Rocketronics ELS in their largest size (My target lathe is 15" LrBlond).



For sure there are challenges with homebrewing any of these systems and the Rocketronics stuff looks like it will be good and it should be available any day now.

I'd only wonder about two things, first will it actually be easier than a DIY solution and second, what happens if the manufacturer goes out of business and the device breaks down. If I did it myself I'd have the skills to fix it, purchasing something in a black box I'm not sure....

Sure it's a relatively small cost ~$250 but you still need to do all the electro/mechanical bits like hooking up the steppers to your machine so it's not plug-n-play by any stretch of the imagination. I'd be more inclined to try the Clough42 ELS since it's opensource and available on github but that's just me (I am typing this on an Ubuntu workstation right now ).

Neither product is actually available for purchase right now so there's time to do more research before laying down your hard earned dollars/euros.

I'm following because although I have almost all the change gears for my Seneca Falls 9x5 I'd rather punch in a number than fiddle with them for doing feeds and threading.

Cheers,

John


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## kb58

matthewsx said:


> ...Neither product is actually available for purchase right now so there's time to do more research before laying down your hard earned dollars/euros....


Well, the Clough42 "product" will only be a small board that combines several functions that several separate off-the-shelf products already perform. The CPU, display board, servo, driver, encoder, and power supplies are also off-the-shelf products. I have it running now as a cobbled-together mess, just to prove it runs. The idea is to get his board when it's done, but all that will do is eliminate a couple of the individual boards; it doesn't really do anything new.

I guess what I'm saying is that if you want to build one now, you can without needing to wait on anything.


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## matthewsx

kb58 said:


> <snip>
> I guess what I'm saying is that if you want to build one now, you can without needing to wait on anything.




That's what I gathered from Github. 

Pictures of what you've done?


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## Dabbler

well... sort of.  Matching the driver boards to the steppers, and to the logic board isn't a slam dunk.  In the sense that you can buy and entire kit from Rocketronics, it makes the procurement part a one-stop-shop.  The Clough42 solution would be a LOT cheaper, but I just don't want the uncertainty of doing it myself.  I'm not really worried about reliability and fixing:  the Rocket solution has a very good rep, and good customer service.

I'm not totally decided yet, but at the moment I'm leaning that way.  If the Clough42 option seems more like what I'm okay with, then I'll probably go that way instead.  I've got time to wait and see how things fall out.


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## kb58

matthewsx said:


> That's what I gathered from Github.
> 
> Pictures of what you've done?


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## kb58

Dabbler said:


> well... sort of.  Matching the driver boards to the steppers, and to the logic board isn't a slam dunk.  In the sense that you can buy and entire kit from Rocketronics, it makes the procurement part a one-stop-shop.  The Clough42 solution would be a LOT cheaper, but I just don't want the uncertainty of doing it myself.  I'm not really worried about reliability and fixing:  the Rocket solution has a very good rep, and good customer service.
> 
> I'm not totally decided yet, but at the moment I'm leaning that way.  If the Clough42 option seems more like what I'm okay with, then I'll probably go that way instead.  I've got time to wait and see how things fall out.


I probably have about $350 into the Clough42 build end-to-end, with about $300 of that being the pulleys, belts, servo, driver, encoder and power supply. Those costs will have to be added on to the Rocketronics unit as well, so it does add up.


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## Qtron

Briney Eye said:


> You found me.  I don't have any backlash compensation because it's not CNC, just a programmable "gearbox".  The number of pitch selections is arbitrary.  I've implemented every pitch that I could find in online pictures of lathes, and every tap available from McMaster-Carr.  I stopped short of having an arbitrary programmable option, but it would be possible.  I did limit it to 4tpi just because I have a small lathe.  That's getting to be some serious depth of cut, and I have already noticed some "hiccups" cutting an 8tpi Acme thread in 1144.  I'm waiting for more timing pulleys and belts so that I can gear it down from the current 4:1 ratio between the stepper and the screw.  I'm planning to test it at 5-, 6- and 8-to-1.
> 
> I still have more to do.  The touch screen is great for a lot of things, but on-the-fly feed direction control needed something more tactile, so I've added a toggle switch mounted in front of the headstock.  I quickly programmed it to control the direction, but have to add jogging support still.  I just got sidetracked by actually making some things.
> 
> I think it would be cool to do cut knurling, so I'm also thinking of adding support for multi-start threads, but that's a ways off yet.  I've only used half the RAM on the Mega so far, so there's still room to squeeze more features in .  I promise to make at least a basic version of the code available at some point when I'm satisfied with it.
> 
> -Jon


wow thanks Jon, glad to "meet". Thanks for the detailed reply - it takes time to draft something logically, so appreciate your time spent very much. EXCELLENT work & love the tidy background shots of your shop! (You are not gunna see mine!! - yet).  
yeah funny how work gets in the way of research/fun.
I have reviewed a few ELS designs on youtube: 
1.  *Rocketronics.de*, Germany, 



  a turnkey product, not arduino related AFAIK, he does use an Atmel,  very pricey (converting to Aussie dollar plus freight. He drives the X axis as well, so the thread cutting process is looped, down to the finish cut.. more to contemplate for you?! Your display is far more user friendly.
 [I cant see the point of designing something that makes U feel all technophobic- which happens regularly here].

 2.  *Clough42* 



He uses a heavy duty TI MCU with on board hardware handling of encoders to avoid excessive interrupts, & a floating point processor-> not sure of that animal at all. He claims only a 1/10thou threading error after running lathe for 15 min.!! (dunno where the error relates back to, i think its in the math cycle inside his Ouiji board beast). No X axis drive, 7 segment Leds & buttons display only.
- Any Threading errors occuring for you, Jon?

3.  https://www.*wadeodesign.com*/cnc-lathe-documentation.html 
"I've been a Mechanical Engineer for about 25 years and have always liked the challenges and rewards of creating solutions to problems.  My interests in building as a hobby originated from working with my Father in his wood shop where he built every piece of furniture the family ever owned and has a passion for building diy style". Heartwarming, a dedicated man indeed  
This guy has also been thorough, highly detailed doc'n (B.O.M with links to suppliers, costings) & vids,  using a Grizzly 10x22 bench top lathe, threw away the guts of the gearbox & put the stepper in there, avoiding stepper overhang at the other end. X axis 'Clearpath' servo is behind lathe not on the apron. A half-nut microswitch is used. The X axis handwheel does jut out more to accomodate the AMV-102 settable capacative low cost encoder.
The Z axis handwheel remained in situ!
- his youtube clip shows a simple display but with surprising functionality, including *3 memory settings*. His concept is to have the lathe used in manual mode, standalone arduino controlled ELS, but then switchable to Mach4 for full CNC.
With x axis powered, threading is looped too..
He uses 2 encoders on Z & X axis which enables a DRO function on the same "simple" screen! His arduino must be doing overtime,, no mention of any threading errors, .. [so maybe *Clough42* an overkill?]
.. Starting to get hard to remember who done what!
   - so much talent out there, makes me wonder whats next. 
Your colour touch LCD display is a real drawcard, but agree that messing with a touchscreen in the middle of a cut is a bit dicey, cant beat a switch to grab a hold of. Sounds like all threads catered for.. gas / plumbing threads?

  The addition of the X axis would be a real drawcard . In no way am I down playing your efforts here! not sure what U meant by 8 TPI hiccups but i presume it wasnt pretty.. But am sure u can fix it.
Yep knurling a great idea, Jon.
No point in releasing anything unless you are happy - will gladly wait. (My old Taiwanese lathe rattles like crazy with the backgears - i hate cutting threads for fear of the neighbours. The metric 127 gear has lost its mate, so cant cut metric ATM).

Getting an Arduino to do anything is a sheer fluke for this 64 yr old 'newbie' - analogue electronics is far more familiar here.
another aspect of a concept i have, is to drive the spindle from a stepper, with angular displacement control/readout,  so as to cut long spirals or splines/flutes with a toolpost mounted router - woodwork stuff
Incidentally I bought a TI Launchpad & built the Touch DRO. I decided to 'bury' it in thickish aluminium, making it military almost, & sprayed it a bronze colour after seeing Ian on "Full custom garage" spray a car in similar. But i had trouble getting the display to read properly with the cheap chinese scales. No issues with the 'proper' Igageing Easy-View scales. Yuri couldn't help here.

Cheers, QTRON.


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## Briney Eye

My shop looks tidy only because of careful framing.  It's a wreck, and I barely have room to turn around, which is why I planned to build a detached shop this year about three times the size, but it's looking more like a spring thing all the time.

I'm sticking with the "programmable gearbox" concept for the foreseeable future.  No CNC for me, thank you.  I still might look at a micro with quadrature decoding at some point.  I have no need for floating point the way I'm doing things.  I have interpolation error but no accumulation of rounding error, and I can stop at a limit on the same count all day long, better than I can measure with a tenth indicator.

I gave very serious consideration to the Clearpath servos, but cheaped out.  The "hiccups" I'm seeing are momentary stalls on heavy cuts that aren't quite big enough to cause my microstepper driver to error out.  I think I can fix it by increasing the gear ratio between the motor and lead screw.  I'm currently running 4:1, but have ordered timing pulleys and belts that will allow me to test 5-, 6- and 8-to-one.  If that's still not enough, I might start thinking about Clearpath again.  They have one that ought to be a drop-in, and would double the torque.  I just balk at the price tag.

I've been reasonably happy with my TouchDRO setups.  I'm using Shars scales with added decoupling caps in the heads to make them more stable.  I have the cross feed scale on the lathe mounted above the screw, covered and completely out of the way, and I would have a hell of a time doing that with any other kind of scale.  About the only possibility would be a DroPros magnetic scale.  I wish Yuriy would get fired up and fix a few things, but he seems to have moved on.

Take care.


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## Qtron

Dabbler said:


> well... sort of.  Matching the driver boards to the steppers, and to the logic board isn't a slam dunk.  In the sense that you can buy and entire kit from Rocketronics, it makes the procurement part a one-stop-shop.  The Clough42 solution would be a LOT cheaper, but I just don't want the uncertainty of doing it myself.  I'm not really worried about reliability and fixing:  the Rocket solution has a very good rep, and good customer service.
> 
> I'm not totally decided yet, but at the moment I'm leaning that way.  If the Clough42 option seems more like what I'm okay with, then I'll probably go that way instead.  I've got time to wait and see how things fall out.


I would be interested in your comments, Dabbler, on my comparisons, summary, presented to Jon, Briney Eye re ELS, in particular Wade'O design's efforts, scope of ELS stand alone part of his design. BTW thanks for your comment re Rocketronics good customer service.
Another excellent  DRO supplier from Germany is Caliper2pc, https://www.caliper2pc.de/en_index.html, a pc based DRO that can be used in conjunction with Mach3. Has some clever 'wizards' too. Uses Chinese scales, definitely a better investment than TouchDRO.


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## GreatOldOne

Good news: James has started selling his connection / boost board. Bad news - the first batch of 100 sold out in about 4 hours...






He‘s going to be making more, so for US peeps here’s the link 





						Electronic Leadscrew Interface PC Board – Clough42, LLC
					






					clough42.com
				




and for us international types, it’s all through eBay








						CLOUGH42 Electronic Leadscrew (ELS) Booster Pack Interface PC Board  | eBay
					

Find many great new & used options and get the best deals for CLOUGH42 Electronic Leadscrew (ELS) Booster Pack Interface PC Board at the best online prices at eBay! Free delivery for many products.



					www.ebay.co.uk
				




luckily for me, I snagged one as soon as his latest video dropped.


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## GreatOldOne

Yay! My HTD pulleys and belt arrived. Guess I know what I’ll be doing tomorrow then.


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## ttabbal

I missed the board, hopefully he'll get more soon. What pulley sizes are you going with?


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## GreatOldOne

72 & 24 tooth HTD M3 x 15mm, so the same 3:1 ratio as James. Seemed to be the easiest way forward as he’s proven that it works with the hybrid stepper / servo


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## GreatOldOne

Busy day in the shop. Both HTD pullies have been bored to the correct size for their respective shafts, and the larger of the two has had a 4mm key way broached in it. This was my first time broaching!
















Checking the fit with a 16mm endmill, prior to broaching. Nice close sliding fit





of course my arbor press didnt have enough daylight between the ram and the broach. I had to do a double boost and add a lower floor. 











Both pulleys still need to be drilled and tapped for set screws, but that’s for another day.

Ive laid out some art work mirroring what James has engraved into his enclosure. I’ve 3d printed my enclosure lid, so needed some way of putting the text on there. Heavy duty laser labels do the job nicely.









I laid the label over the whole lid with the intention of neatly cutting out all of the apertures... but it’s a real pain to get a nice neat edge and the aluminium foil labels dull craft knives real quick. So I just used the majority of the label for alignment, and then removed what wasn’t needed. Not as elegent as a CNC engraved lid, but functional.


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## GreatOldOne

My OCD got the better of me, and I re-did the decal. I think it looks better now, and it sort of looks like an old C60 cassette. Awesome Mix ELS Edition? 






I've put the decal file on my drop box, just in case anyone else wants to use it. Link:









						ELS Lid Decals.svg
					

Shared with Dropbox




					www.dropbox.com
				




Print it out, use a light behind it to line it up with the lid if you've printed one - and one you've got it stuck down use a craft / xacto knife to cut around the dotted lines and the perimeter.


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## Qtron

Briney Eye said:


> My shop looks tidy only because of careful framing.  It's a wreck, and I barely have room to turn around, which is why I planned to build a detached shop this year about three times the size, but it's looking more like a spring thing all the time.
> 
> I'm sticking with the "programmable gearbox" concept for the foreseeable future.  No CNC for me, thank you.  I still might look at a micro with quadrature decoding at some point.  I have no need for floating point the way I'm doing things.  I have interpolation error but no accumulation of rounding error, and I can stop at a limit on the same count all day long, better than I can measure with a tenth indicator.
> 
> I gave very serious consideration to the Clearpath servos, but cheaped out.  The "hiccups" I'm seeing are momentary stalls on heavy cuts that aren't quite big enough to cause my microstepper driver to error out.  I think I can fix it by increasing the gear ratio between the motor and lead screw.  I'm currently running 4:1, but have ordered timing pulleys and belts that will allow me to test 5-, 6- and 8-to-one.  If that's still not enough, I might start thinking about Clearpath again.  They have one that ought to be a drop-in, and would double the torque.  I just balk at the price tag.
> 
> I've been reasonably happy with my TouchDRO setups.  I'm using Shars scales with added decoupling caps in the heads to make them more stable.  I have the cross feed scale on the lathe mounted above the screw, covered and completely out of the way, and I would have a hell of a time doing that with any other kind of scale.  About the only possibility would be a DroPros magnetic scale.  I wish Yuriy would get fired up and fix a few things, but he seems to have moved on.
> 
> Take care.


just saw your Youtube torque test Jon, Wow , the forces involved on a leadscrew = vicious!! no wonder 1/2 nut backlash eventuates 
Jon Bryan
8 hours ago, youtube.
"Down the rabbit hole I go. I'm trying to score a force gauge and actually measure it. Rough T = KDP calculation gives me a number between 550 and 1100 pounds of force applied to the carriage depending on the friction loss. I can tell you that even before I geared it down I could push on it my hardest without slowing it down, and I weigh about 270, so I'm inclined to believe the rough calculation.  Gives you an appreciation for the kind of cutting forces that are involved when cutting an 8tpi thread."
So,
  Not being a mech engineer or F & T, i need clarification here: T = KDP?? (so something related to diametral pitch?).. 
(wikipedia = Kurdistan Democratic Party, lol.) its ok, i'll dig for it..
Why not simply do lots of light cuts, (- nicer job? ) 
 to ease up the forces on the 1/2 nuts, leadscrew, bearings etc? After all U don't cut an 8 TPI thread very oft, do you? 
Well i don't anyway, & if needed, i wouldn't be in too great a hurry.

- i Just got an answer from Clough42 re his ELS, man is he gunna be busy, new breakout boards for his TI piccolo sold out in hrs!!
I don't quite get the rush, after all he said the board isn't crucial to the project, but nice to have pretty lights to indicate activity, i suppose. 
James advised me re your latest Vid., Thanks to him, & certainly, thanks to you - the torque wrench was a profoundly simple way to indicate static stepper torque or holding force. [some drives can be set to 50% idle current, or standstill current ('Leadshine' terminology!) reducing heat build up in the stepper windings].
Q: U seem to be operating a closed loop stepper, it cant be a system reaction to the spindle encoder movement, as there's no direct link from the spindle cog & fwd/rev idlers to the gearbox input anymore, being the point of the ELS!
i mean, i get the holding control of the stepper drive, resisting forced steps, but after 1 step overcome mechanically, i would have thought it would lock into that new step, not go back as depicted, which seemed to be a heap of steps. (unless its a closed loop). Puzzled.
Also, about those idlers & the encoder drive train, wouldn't there be too much backlash / slop between spindle motion & the encoder rotation, given they are only spur gears? I get the need to sense fwd/rev. but that can be done direct off the spindle, with virtually no missed pulse edges.
Maybe i missed something there, too 

I do hope U find that suitable force gauge..
cheers, Qtron.
P.S.  A blank Mega awaits, Tongue hanging out for that magic code now Sir Jon!!


----------



## kb58

GreatOldOne said:


> ...the first batch of 100 sold out in about 4 hours...


Two hours, and I was the first to lose out. Went to Ebay and it said he had two left. Ordered two and it said, not enough in stock. Ordered one, hit Buy, and "sorry, all out." I think I'm one of the few who actually has the entire thing running; I have the discrete boards but I just like how his board cleans up the wiring. I'm pushing forward on getting it entirely finished such that his board is the only holdup.

To be honest, I'm not quite sure why I decided to put the assembly on the lathe itself instead of the wall. I guess I just like knowing that if I have to move the lathe, there aren't any "appendages" other than the power cord. And yes, there will be a cover over the assembly, because with 0.020 pitch on a couple of the ICs on the development board, it wouldn't take much for a chip to short out things...

Separately, I have no idea if the little belt I'm using will be sufficient for driving the carriage, because there's probably a dozen variables in figuring out the torque. Speed of cut, depth of cut, cutter type, cutter sharpness, material being cut, spindle speed, gear reduction of lead screw, gear reduction of QCGB, gear reduction of belt pullies, torque capacity of the servo motor, and probably more I'm forgetting.


----------



## GreatOldOne

kb58 said:


> Two hours



Insane. I must have been very fortunate to get one of the first batch then.


----------



## RJSakowski

kb58 said:


> Two hours, and I was the first to lose out. Went to Ebay and it said he had two left. Ordered two and it said, not enough in stock. Ordered one, hit Buy, and "sorry, all out." I think I'm one of the few who actually has the entire thing running; I have the discrete boards but I just like how his board cleans up the wiring. I'm pushing forward on getting it entirely finished such that his board is the only holdup.
> 
> To be honest, I'm not quite sure why I decided to put the assembly on the lathe itself instead of the wall. I guess I just like knowing that if I have to move the lathe, there aren't any "appendages" other than the power cord. And yes, there will be a cover over the assembly, because with 0.020 pitch on a couple of the ICs on the development board, it wouldn't take much for a chip to short out things...
> 
> Separately, I have no idea if the little belt I'm using will be sufficient for driving the carriage, because there's probably a dozen variables in figuring out the torque. Speed of cut, depth of cut, cutter type, cutter sharpness, material being cut, spindle speed, gear reduction of lead screw, gear reduction of QCGB, gear reduction of belt pullies, torque capacity of the servo motor, and probably more I'm forgetting.


I ordered a board yesterday and had a message from Paypal this morning to say it's been shipped.


----------



## ttabbal

RJSakowski said:


> I ordered a board yesterday and had a message from Paypal this morning to say it's been shipped.




I did as well. I think he put a few more up at some point. I just checked here and there and saw 2 available, so I went for it. 

It's not too difficult to build one from the parts he lists. I just wanted to be able to skip that. 

His lathe looks similar in size to my PM1127, so I'm going to try 3:1. My lathe gearbox also has a selectable 2:1 I can add in if needed.


----------



## RJSakowski

I've been following James for some time now.  Originally, I was planning on waiting until all the dust settled before diving in but given the popularity of this project, I decided that I had best get going on it.  Over the weekend, I ordered all the electronics save the stepper/servo driver.  Everything except the I/O interface has been shipped. 

I am still waiting to see the final verdict on the choice of motors and pulley size.   I have found several candidates for motors, a conventional stepper, and a hybrid stepper/ servo.  I expect that the maximum lead screw RPM will be in the neighborhood of 600.  At 600 RPM, that would be moving the carriage at 50 ipm which is crazy fast. If I were cutting a 4 tpi thread for some unknown reason, threading at the 150 RPM spindle speed would mean the lead screw would be turning at 450 RPM   The torque/speed curves for steppers vary quite a bit from motor to motor but it looks reasonable to expect a 50% drop in torque at 600 RPM. 

I modified the opening at the bottom of the lathe bed to accommodate either a NEMA 23 or NEMA 24 frame motor.


----------



## Briney Eye

Qtron said:


> just saw your Youtube torque test Jon, Wow , the forces involved on a leadscrew = vicious!! no wonder 1/2 nut backlash eventuates
> Jon Bryan
> 8 hours ago, youtube.
> "Down the rabbit hole I go. I'm trying to score a force gauge and actually measure it. Rough T = KDP calculation gives me a number between 550 and 1100 pounds of force applied to the carriage depending on the friction loss. I can tell you that even before I geared it down I could push on it my hardest without slowing it down, and I weigh about 270, so I'm inclined to believe the rough calculation.  Gives you an appreciation for the kind of cutting forces that are involved when cutting an 8tpi thread."
> So,
> Not being a mech engineer or F & T, i need clarification here: T = KDP?? (so something related to diametral pitch?)..
> (wikipedia = Kurdistan Democratic Party, lol.) its ok, i'll dig for it..
> Why not simply do lots of light cuts, (- nicer job? )
> to ease up the forces on the 1/2 nuts, leadscrew, bearings etc? After all U don't cut an 8 TPI thread very oft, do you?
> Well i don't anyway, & if needed, i wouldn't be in too great a hurry.
> 
> - i Just got an answer from Clough42 re his ELS, man is he gunna be busy, new breakout boards for his TI piccolo sold out in hrs!!
> I don't quite get the rush, after all he said the board isn't crucial to the project, but nice to have pretty lights to indicate activity, i suppose.
> James advised me re your latest Vid., Thanks to him, & certainly, thanks to you - the torque wrench was a profoundly simple way to indicate static stepper torque or holding force. [some drives can be set to 50% idle current, or standstill current ('Leadshine' terminology!) reducing heat build up in the stepper windings].
> Q: U seem to be operating a closed loop stepper, it cant be a system reaction to the spindle encoder movement, as there's no direct link from the spindle cog & fwd/rev idlers to the gearbox input anymore, being the point of the ELS!
> i mean, i get the holding control of the stepper drive, resisting forced steps, but after 1 step overcome mechanically, i would have thought it would lock into that new step, not go back as depicted, which seemed to be a heap of steps. (unless its a closed loop). Puzzled.
> Also, about those idlers & the encoder drive train, wouldn't there be too much backlash / slop between spindle motion & the encoder rotation, given they are only spur gears? I get the need to sense fwd/rev. but that can be done direct off the spindle, with virtually no missed pulse edges.
> Maybe i missed something there, too
> 
> I do hope U find that suitable force gauge..
> cheers, Qtron.
> P.S.  A blank Mega awaits, Tongue hanging out for that magic code now Sir Jon!!



The equation appears in slightly different forms.  Of course it's a simplification. The terms are:

T = Torque (in lb)
K = Coefficient of Friction (dimensionless, ranges typically between 0.1 - 0.2)
D = Major diameter of the screw (inches)
P = Force (lbs)

If you rearrange the terms to solve for Force, input 88.5 in-lbs of torque (10Nm), and assume the friction coefficient for a 3/4" screw is the worst-case 0.2, you get:
P = 88.5 / (0.2 * 0.75) = 590 pounds of force applied by the screw.

Caveat: I'm not an engineer, I just spent a lot of years working for them.

Yes, it's a closed-loop microstepper.  In the absence of steps it tries to stay where it is. What you're describing is precisely the behavior of an open-loop stepper.

I drive the encoder from the stud gear for simple expedience. It was the easiest and closest. As long as things are in motion backlash can be ignored. When you change direction the backlash is what it is. But that's the normal state of affairs anyway. CNC machines go to an enormous amount of trouble to minimize the backlash because they're changing direction all the time and the less they have to compensate for it the better.


----------



## RJSakowski

The two questions I still have are: 1. What is the maximum torque that the lead screw will encounter during turning or threading and 2. what does the torque speed curve look like for any given choice of motor.

The first is dependent upon the depth of cut, the feed rate, the material being cut, and the geometry of the cutting tool. The relationship between the input torque on the lead screw and the delivered force, neglecting friction, is torque x rotational angle = force x distance.  My lead screw has 12 tpi and therefore moves .08333/ revolution and ine revolution is equal to 2π radians so the force delivered = torque x 2π/.0833 =75.4 x torque (torque in lb.-in. and force in lb.).  If my input to lead screw is 200 oz.-in, or 12.5 lb.-in., I could deliver 940 lbs. of force to the carriage drive, less frictional losses.  My carriage crank has a mechanical advantage of 11:1 so I would have exert around 85 lbs of force at the crank to create the same 940 lbs.

The second question is more difficult to answer.  When I dealt with NEMA 11 and NEMA 17 steppers in the past, I had published torque speed curves to guide my selection.  Unfortunately, the motors that I have seen for this application don't seem to have that information available.  Additionally, looking at a variety of motors on line, there doesn't seem to be a set relationship between holding torque and and available torque at speed.   I am considering two motors at the present; a stepper with 425 oz.-in. of torque and a hybrid stepper with 602 oz.-in of torque.  My gut is telling me to go with the more expensive hybrid but I really would like to see some torque curves for it.  The hybrid can run at higher rpm so torque multiplication via gears is an option.  Unfortunately, conventional steppers don't enjoy the same advantage due to the serious decline of available torque at increases rpm.

As to actually measuring torque, it should really be done at the desired operating speed.  A dynamometer would be useful.  A simple one could be constructed using a brush type motor.  A cordless drill/driver comes to mind.  The speed control would for the drill would have to be disconnected and the two power leads connected to a variable resistance.  The voltage across the resistance and the current through the resistance would be monitored as the resistance was slowly decreased until the stepper lost steps or the hybrid errored out.  The product of the voltage times current would be the output power in watts which could be converted to horsepower at 748 watts/hp.  Horsepower - torque x rpm/5252 so, knowing the rpm, you can calculate the delivered torque.  Torque in lb.-ft. can be converted to oz.-in. by multiplying by 12 x 16.


----------



## GreatOldOne




----------



## RJSakowski

All parts are ordered.  I decided to go with 600 oz.-in. hybrid stepper, https://www.ebay.com/itm/1-Axis-Clo...928169?hash=item3654528529:g:yDwAAOSwVMFdfyOU and a 1:1 gear ratio.  I am a little concerned as James used  a 3:1 gearing for an output torque of 900 oz.-in. but I can always fall back on the 2:1 gearing in my gear box if necessary.  

I did some measurements of torque required to turn the engaged lead screw and was somewhat surpised to see that it required 370 oz.-in. of torque to turn the unloaded lead screw.  My Tormach 770 uses a 500 oz.-in. stepper to drive a 5mm ball screw and I have not had problems with lost steps with it.  A little investigation lead to the discovery of overly tight half nuts.  With the half nuts disengaged, the torque required to turn the gear box gears and lead screw was 80 oz.-in.  With the half nut lever backed off ever so slightly, the torque was 150 - 190 oz.-in.  Backlash increased from .001" to .002".  It doesn't appear that the half nut mechanism is adjustable but I may be able to use a shim to limit the amount of closure.


----------



## alan856

Dabbler said:


> There's a nice ELS from Germany that they call an Electronic Lead Screw - Stefan Gotteseinter did a review of it on his youtube channel.  They will have a complete English manual available early this year. It leaves manual operation untouched and is DIY for the home machinist.


Greets!  I am a proud owner of an ELS3 from Louis Schreyer (Rocketronics, Germany). It has been installed on an LMS-3536 (Sieg SC4) lathe. I have some photos of the installation if any body is interested.  Also I'd like to start a thread (where?) where we can discuss ELS vs CNC.

Currently Stefan's company (Rocketronics.de) has no English manuals. Even though his site indicates such - they are still in German. You can get the PDF and use Google Translate to get a reasonable version.  I also think he is currently not selling to the US - I guess there is too much red tape!

On of the immediate "PROs" of having the lathe controlled by cpu/steppers is that the feed-rate is ALWAYS constant and you can stop at the SAME place every time!  What amazing finishes you get... And of course the nearly infinite threading capability is yet another story... plus you can do curves and tapers and balls...
Personally I have no interest in CNC on a lathe - MAYBE on the mill.  A good ELS gives you the flexibility of manual turning with the precision and control of a "computer" driven machine.


----------



## Dabbler

alan856 said:


> Currently Stefan's company (Rocketronics.de) has no English manuals.



That is no longer true.  The English manuals for all versions can be downloaded from the Rocketronics site. 

 I was unaware that Stefan was associated with Rocketronics, but rather I thought  he liked their unit and used it on his previous lathe...



alan856 said:


> Personally I have no interest in CNC on a lathe - MAYBE on the mill. A good ELS gives you the flexibility of manual turning with the precision and control of a "computer" driven machine.



I agree.  The need to learn such a depth of tools makes CNC less attractive than a purpose-built ELS for me anyway.


----------



## Qtron

RJSakowski said:


> clipped..
> 
> The second question is more difficult to answer.  When I dealt with NEMA 11 and NEMA 17 steppers in the past, I had published torque speed curves to guide my selection.  Unfortunately, the motors that I have seen for this application don't seem to have that information available.  Additionally, looking at a variety of motors on line, there doesn't seem to be a set relationship between holding torque and and available torque at speed.   I am considering two motors at the present; a stepper with 425 oz.-in. of torque and a hybrid stepper with 602 oz.-in of torque.  My gut is telling me to go with the more expensive hybrid but I really would like to see some torque curves for it.  The hybrid can run at higher rpm so torque multiplication via gears is an option.  Unfortunately, conventional steppers don't enjoy the same advantage due to the serious decline of available torque at increases rpm.
> 
> As to actually measuring torque, it should really be done at the desired operating speed.  A dynamometer would be useful.  A simple one could be constructed using a brush type motor.  A cordless drill/driver comes to mind.  The speed control would for the drill would have to be disconnected and the two power leads connected to a variable resistance.  The voltage across the resistance and the current through the resistance would be monitored as the resistance was slowly decreased until the stepper lost steps or the hybrid errored out.  The product of the voltage times current would be the output power in watts which could be converted to horsepower at 748 watts/hp.  Horsepower - torque x rpm/5252 so, knowing the rpm, you can calculate the delivered torque.  Torque in lb.-ft. can be converted to oz.-in. by multiplying by 12 x 16.


Ha U hitting nail on the head here, THANKS for your entry!
I had a 'wrestling match' with a 'Leadshine' supplier, SteppersOnline-OMC, an otherwise good chinese communicator, who delivered a couple of nice grunty Nema 34's to me. But, on this matter, & best they could manage from their Eng. dept., was a rule of thumb for Holding vs running torque. pfft.
Not worth quoting here, too vague, & too long ago too.
If U dig hard enough, its findable, (generalised graphs), but maybe not for your specific motor.
- i am hoping Briney eye will clarify, soon, (Jon's) Torque wrench test is of course a holding torque test only.
BTW, it would have to be a hell of a drill! esp for Nema 34, thru a reduction pulley setup. AND, you would need to know the efficiency of the motor/generator, to get close to the mark, yes?-> i do appreciate the approach tho, & have used the method on a home-made, low powered VSD once. [I used a digital audio power amp, 300W, to drive a single phase cap run motor- no, don't try it - a real time sink!!] 
Qtron


----------



## Qtron

DIY dyno = 24V 200 watt brush motor, on a 1:1 pulley to a single ph. ( motor run cap) 340 watt motor.
(
	

		
			
		

		
	






	

		
			
		

		
	
cast casing unrelated)


----------



## Qtron

RJSakowski said:


> clipped
> ..  I am considering two motors at the present; a stepper with 425 oz.-in. of torque and a hybrid stepper with 602 oz.-in of torque.  My gut is telling me to go with the more expensive hybrid but I really would like to see some torque curves for it.  The hybrid can run at higher rpm so torque multiplication via gears is an option.  Unfortunately, conventional steppers don't enjoy the same advantage due to the serious decline of available torque at increases rpm.


A
I Meant to say, I am surprised that non-hybrid steppers are still avail, given the Chinese output of fairly good to real nice hybrids these days..


----------



## Qtron

Briney Eye said:


> The equation appears in slightly different forms.  Of course it's a simplification. The terms are:
> 
> T = Torque (in lb)
> K = Coefficient of Friction (dimensionless, ranges typically between 0.1 - 0.2)
> D = Major diameter of the screw (inches)
> P = Force (lbs)
> 
> If you rearrange the terms to solve for Force, input 88.5 in-lbs of torque (10Nm), and assume the friction coefficient for a 3/4" screw is the worst-case 0.2, you get:
> P = 88.5 / (0.2 * 0.75) = 590 pounds of force applied by the screw.
> 
> Caveat: I'm not an engineer, I just spent a lot of years working for them.
> 
> Yes, it's a closed-loop microstepper.  In the absence of steps it tries to stay where it is. What you're describing is precisely the behavior of an open-loop stepper.
> 
> I drive the encoder from the stud gear for simple expedience. It was the easiest and closest. As long as things are in motion backlash can be ignored. When you change direction the backlash is what it is. But that's the normal state of affairs anyway. CNC machines go to an enormous amount of trouble to minimize the backlash because they're changing direction all the time and the less they have to compensate for it the better.


Thanks again for your reply, the math, - for some reason i didn't get email notification so missed your response, till now. (was waiting with bated breath!)
so to clarify, for me, & those who have just dropped in on this thread, are you saying that 590 lbf or 2,624N is the lateral force applied to the carriage via the 1/2nuts, with your 3:1 stepper arrangement, driving the leadscrew? (and not via the gearbox). 
And is that enough to do more gentle, but not 'toy-ish', depth of cuts for an 8 TPI thread?


----------



## Qtron

RJSakowski said:


> I've been following James for some time now.  Originally, I was planning on waiting until all the dust settled before diving in but given the popularity of this project, I decided that I had best get going on it.  Over the weekend, I ordered all the electronics save the stepper/servo driver.  Everything except the I/O interface has been shipped.
> 
> I am still waiting to see the final verdict on the choice of motors and pulley size.   I have found several candidates for motors, a conventional stepper, and a hybrid stepper/ servo.  I expect that the maximum lead screw RPM will be in the neighborhood of 600.  At 600 RPM, that would be moving the carriage at 50 ipm which is crazy fast. If I were cutting a 4 tpi thread for some unknown reason, threading at the 150 RPM spindle speed would mean the lead screw would be turning at 450 RPM   The torque/speed curves for steppers vary quite a bit from motor to motor but it looks reasonable to expect a 50% drop in torque at 600 RPM.
> 
> I modified the opening at the bottom of the lathe bed to accommodate either a NEMA 23 or NEMA 24 frame motor.


i went back & looked at old emails from Stepperonline, ha, i am wrong, as it was a specific answer, not a rule of thumb,
they quoted 0.75Nm driving torque, at 200 RPM, 2.8 Amps, Full step, with a hybrid stepper  having a 1.26Nm (178.4oz.in), 2.8A, Holding Torque.
Of course that all becomes wrong at microstepping rates, sinusoidal driving, and who knows what it would be at 1000 RPM.
My understanding is max torque is achieved at full steps only, slow speeds only.. (and no mechanical resonance happening, which shouldn't below mid band resonance freq's). BTW, my assumption here, a leadscrew driven via a "rubber band" toothed pulley may not have sufficient direct coupling to the stepper to dampen this resonance.
Wikipedia: 
When the motor moves a single step it overshoots the final resting point and oscillates round this point as it comes to rest. This undesirable ringing is experienced as motor vibration and is more pronounced in unloaded motors. An unloaded or under loaded motor may, and often will, stall if the vibration experienced is enough to cause loss of synchronisation.
Stepper motors have a natural frequency of operation. When the excitation frequency matches this resonance the ringing is more pronounced, steps may be missed, and stalling is more likely. Motor resonance frequency can be calculated from the formula:





f = 100/2pi x sq.root of 2pMh/Jr
Mh Holding torque
N·mp Number of pole pairs
Jr Rotor inertia kg·m²


----------



## Briney Eye

Qtron said:


> Thanks again for your reply, the math, - for some reason i didn't get email notification so missed your response, till now. (was waiting with bated breath!)
> so to clarify, for me, & those who have just dropped in on this thread, are you saying that 590 lbf or 2,624N is the lateral force applied to the carriage via the 1/2nuts, with your 3:1 stepper arrangement, driving the leadscrew? (and not via the gearbox).
> And is that enough to do more gentle, but not 'toy-ish', depth of cuts for an 8 TPI thread?


I measured 10Nm static torque from my 5:1 setup, and the equation estimates that should provide 590 pounds of force on the end of the screw (or on the half nuts). There is further friction loss in the half nuts, and more in the sliding friction of the carriage.
I'm now the owner of a 1000lb dial force gage, and will be trying to rig something up to measure the force on the carriage when it stalls. I was busy making a precision slitting saw arbor yesterday, and I have another project to finish today, though.
I've also mounted a 120-tooth timing pulley and am running an 8:1 ratio right now. I should shortly have a 12-tooth pulley for the motor and can go to 10:1. The 120T pulley just fits under the cover, and overlaps the encoder pulley (but clears). Pulley/belt availability has improved markedly since I began this project. There must be a lot of people doing this kind of thing.


----------



## Qtron

yeah, hey sorry re that drive ratio error, been jumping across too many ELS stories!
am not in favour of hi pulley ratios tho as lead screw speed will drop off, without using a servo motor, so gentle cuts on long-ish threads may become tediously time consuming, yes?
BTW, I bought a reasonable taiwanese MT3 slitting arbour, cos time vs $$ didnt add up, but well done bro.
Go easy on ur machine! 1000lb on 1/2 nuts for 3/4" dia screw is nasty


----------



## Briney Eye

Qtron said:


> Thanks again for your reply, the math, - for some reason i didn't get email notification so missed your response, till now. (was waiting with bated breath!)
> so to clarify, for me, & those who have just dropped in on this thread, are you saying that 590 lbf or 2,624N is the lateral force applied to the carriage via the 1/2nuts, with your 3:1 stepper arrangement, driving the leadscrew? (and not via the gearbox).
> And is that enough to do more gentle, but not 'toy-ish', depth of cuts for an 8 TPI thread?


I forgot to mention that the static torque is scaling with the change in ratio.
Also, I have the microstepper set to 800 steps per revolution, which is as low as it will go. I don't know if it's also the highest-torque setting, but it seems like it ought to be. I doubt that I would be able to measure the difference between 800 and 1000 (where I had it with a 4:1 ratio) though. I guess I should try it and see.


----------



## Briney Eye

Qtron said:


> yeah, hey sorry re that drive ratio error, been jumping across too many ELS stories!
> am not in favour of hi pulley ratios tho as lead screw speed will drop off, without using a servo motor, so gentle cuts on long-ish threads may become tediously time consuming, yes?
> BTW, I bought a reasonable taiwanese MT3 slitting arbour, cos time vs $$ didnt add up, but well done bro.
> Go easy on ur machine! 1000lb on 1/2 nuts for 3/4" dia screw is nasty


I haven't recalculated the lookup tables for the ratio change yet. The step rate will be scaled, and the microstepper is rated to handle up to 200khz, so I think I have enough margin in the Arduino.
I made an expanding mandrel for modifying timing pulleys the other day and my cheap arbor and saw were really bad, so I decided making a good arbor would be good training. I hit all my dimensions to a couple of tenths, so I must be learning something.
These machines can rip their own guts out in low gears, as I have some unfortunate experience with. The stepper motor's torque limit is something of a feature on a machine with no clutch, and I think I'm still far short of the forces change gears can apply (famous last words?).


----------



## Qtron

Briney Eye said:


> I haven't recalculated the lookup tables for the ratio change yet. The step rate will be scaled, and the microstepper is rated to handle up to 200khz, so I think I have enough margin in the Arduino.
> I made an expanding mandrel for modifying timing pulleys the other day and my cheap arbor and saw were really bad, so I decided making a good arbor would be good training. I hit all my dimensions to a couple of tenths, so I must be learning something.
> These machines can rip their own guts out in low gears, as I have some unfortunate experience with. The stepper motor's torque limit is something of a feature on a machine with no clutch, and I think I'm still far short of the forces change gears can apply (famous last words?).


Me getting tenths is impossible,, carpenter wants to blame tools here.. wish I had ballscrews everywhere. Well done indeed.
The higher the drive microstepping rate, the lower the stepper torque.
Re torque, pls clarify cos I am losing the plot here, wouldnt  even 590 lb force on a tool tip,  say HSS, cutting a thread, at speed be a disaster?
Again, why not just do gentle cuts?


----------



## Briney Eye

I haven't worked through the section in Machinery's Handbook on Estimating Machining Power yet, but 590 pounds of force is way down on the scale in this world. Consider that a Grade 8 bolt has a typical tensile strength of 150,000psi. I remember Tom Lipton (oxtools) mentioning the amount of clamping force provided by a #10 screw in his Mini Pallet project a couple of years ago and being surprised. A noob like me isn't used to thinking in those terms.


----------



## RJSakowski

In theory, a stepper has an infinite torque at zero rpm.  In practice, it is limited by the resistance and inductance of the stepper.The theoretical torque is inversely proportional to rpm, torque x rpm = constant.  The constant is dependent upon the geometry of the stepper and its electrical characteristics and will vary within motors of the same frame size and detent torque.  We used to use NEMA 17 motors from Oriental Motors and they have published torque/rpm curves for their motors.  The curves vary quite a bit between similar motors. 

I made a decision on a motor for the 602 based in part on James' success with his hybrid stepper and that my Tormach steppers are 500 oz.-in.  I ordered a 600 oz.-in. hybrid stepper and driver kit, https://www.ebay.com/itm/233342928169 .    I plan on using 1:1 pulleys to drive the lead screw. I'm hoping that the inproved high speed response of the hybrid stepper will be sufficient.   My gut is telling me that the spindle motor will stall first.  If necessary, I can use the 2:1 gearing in the gear box to boost the torque.

My next concern is the power supply.  The stepper has three phase windings and a rated current of 5.8 amps/winding.  Does this mean that I need a power supply with a 20 amp rating?  At 48 volts, that's 1,000 watts. That seems a more than a bit large.  The Tormach has a 400 watt linear supply and is driving two 500 oz.-in steppers and one 700 oz.-on. stepper.


----------



## GreatOldOne

Pleased with my progress today. Enclosure for the electrics / electronics sorted.









Circular connectors for all the connections to the outside world. Smaller 6 pins will be for display, spindle encoder and servo encoder. The larger 4 pin will be for servo power. 









Now I need to wire it all up, and fit a fan on the front cover to ensure a constant flow of air


----------



## Reddinr

So, I think I'm going to take the plunge too.  I've had ELS on my mind for a couple of years now.  I just bought a TI development board to start noodling with.  I am impressed at the depth and thoroughness of his design process.  It is great to see a focused, high-quality design process that is documented that well right out of the gate.  It is also very good that he kept it simple by making it a single purpose implementation to start out.  There is lots of headroom in the chosen processor for added features later.   Well done all around AND he has a day job.   Very inspiring.

My plan is to build up an interface board that has similar functionality as Clough42's but that has differential receivers for the encoder signals because I have some of those encoders and like the noise immunity these encoders may provide.  I have a couple of big motor drives nearby and that concerns me noise-wise.  I will be using Clearpath step/direction servos because I have a couple of them leftover from a prototype I did.  

This is going to be fun!  Thankfully I retire next year so I should actually have some time for it.


----------



## Briney Eye

Qtron said:


> yeah, hey sorry re that drive ratio error, been jumping across too many ELS stories!
> am not in favour of hi pulley ratios tho as lead screw speed will drop off, without using a servo motor, so gentle cuts on long-ish threads may become tediously time consuming, yes?
> BTW, I bought a reasonable taiwanese MT3 slitting arbour, cos time vs $$ didnt add up, but well done bro.
> Go easy on ur machine! 1000lb on 1/2 nuts for 3/4" dia screw is nasty


I said in my earlier posting that 800 steps per rev was as low as my microstepper could go, but that is wrong. The setting in the table that's labeled "default" is 400 steps per rev. I said in an even earlier post that I would soon have a 12T pulley and be able to go to a 10:1 ratio. That was wrong, too. I misread the product description, which is for an HTD5M pulley, not the HTD3M that I'm using. With the 8:1 ratio I have on the machine, at 400 steps per rev, without changing my code, I'm feeding 25% too fast (25,600 steps per inch vs 32,000) already, so there will be no problem with the step rate that I can generate. I don't see any difference in the static torque test at 400 steps per rev vs 800.


----------



## Qtron

Briney Eye said:


> I said in my earlier posting that 800 steps per rev was as low as my microstepper could go, but that is wrong. The setting in the table that's labeled "default" is 400 steps per rev. I said in an even earlier post that I would soon have a 12T pulley and be able to go to a 10:1 ratio. That was wrong, too. I misread the product description, which is for an HTD5M pulley, not the HTD3M that I'm using. With the 8:1 ratio I have on the machine, at 400 steps per rev, without changing my code, I'm feeding 25% too fast (25,600 steps per inch vs 32,000) already, so there will be no problem with the step rate that I can generate. I don't see any difference in the static torque test at 400 steps per rev vs 800.


No probably no diff cos with 1.8° steppers, 400 is 1/2 stepping, 800 is 1/4 stepping, but u will see diff say at full tilt, 1/16th steps vs 1/2. (Should also see a torque diff between full steps & 1/8th stepping rate too).


----------



## Qtron

Briney Eye said:


> I haven't worked through the section in Machinery's Handbook on Estimating Machining Power yet, but 590 pounds of force is way down on the scale in this world. Consider that a Grade 8 bolt has a typical tensile strength of 150,000psi. I remember Tom Lipton (oxtools) mentioning the amount of clamping force provided by a #10 screw in his Mini Pallet project a couple of years ago and being surprised. A noob like me isn't used to thinking in those terms.


Clearly my perspective is wrong then, I am thinking here if wear forces on the brass (mine) 1/2 nuts & on smallish HSS threading tool that has to put up with lateral carriage forces and the rotational force of stock being cut/threaded. Wonder what that would be for 2'' dia, CS1020 steel, 20 thou cut for 8 tpi?!


----------



## Qtron

GreatOldOne said:


> Pleased with my progress today. Enclosure for the electrics / electronics sorted.
> Circular connectors for all the connections to the outside world. Smaller 6 pins will be for display, spindle encoder and servo encoder. The larger 4 pin will be for servo power.
> Now I need to wire it all up, and fit a fan on the front cover to ensure a constant flow of air


pics clipped.
Hiya Great Old One, yes you are! doing quite nicely, i greening up here too.
Procrastination hasn't bitten you!
Um, a Q that i cant seem to find answers for On clough42's site:
 Is there any chance you could list the characteristics, features of his design..
I don't mean a list of all thread choices, 
they maybe in one of his vid's but . Or maybe U can point me in the right direction.
cheers,


----------



## GreatOldOne

Qtron said:


> pics clipped.
> Hiya Great Old One, yes you are! doing quite nicely, i greening up here too.
> Procrastination hasn't bitten you!
> Um, a Q that i cant seem to find answers for On clough42's site:
> Is there any chance you could list the characteristics, features of his design..
> I don't mean a list of all thread choices,
> they maybe in one of his vid's but . Or maybe U can point me in the right direction.
> cheers,



As far as I know it has the following capabilities:


spindle rpm readout
ability to switch between metric & imperial units
foward and reverse the leadscrew independent of the rotational direction of the spindle
feed in a number of different increments (mm or inch) per spindle rev
set a variety of TPI threads
set a variety of mm threads.

This is all from my recollection of features seen in the vids, and probably isn’t exhaustive... he’s also canvesing for additional features to be added on the github page.









						GitHub - clough42/electronic-leadscrew: Lathe electronic leadscrew controller
					

Lathe electronic leadscrew controller. Contribute to clough42/electronic-leadscrew development by creating an account on GitHub.




					github.com
				











						Home · clough42/electronic-leadscrew Wiki
					

Lathe electronic leadscrew controller. Contribute to clough42/electronic-leadscrew development by creating an account on GitHub.




					github.com


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## Qtron

Thanks Greatoldone, & thankyou for the links.
I do hope he adds some of the functionality of Wade'O design's amazing machine, unfortunately no MCU files posted, & no responses from him. Sad indeed. something must have happened. His is a bit like Rocketronics.de,
 with auto in-feeding, cycled down to the final finishing cut.. & much more.


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## alan856

Gents - there is a SUPER ELS ready-to-go from RockeTronics in Germany. ELS4 has just been released and will do EVERYTHING you ever dreamed of with an ELS... and more!  I have the earlier version, the ELS3. I have installed it on a LMS-3536 (Sieg SC-4) lathe.  I will be putting up some pix of the install.

But before you go to all the work of “reinventing this wheel” - take a look at the RockeTronics ELS4. It is plenty of work to just get your lathe “motored-up” let alone design issues of trying to create your own.

Full Disclosure: I am NOT a rep of RockeTronics- just a very satisfied user.
=A.


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## Reddinr

The ELS4 looks like a very fine product and reasonably priced too for what it does.  For me, the fun is as much the journey as the destination.  The ELS4 would get me there faster but I would miss all the planning, debugging, hair pulling, parts throwing, starting over, swearing and learning I get to experience by rolling my own.

Some of the ELS4 documentation shows the Z stepper attached directly to the lead-screw and not through a gearbox.  I suppose that could have some benefits of less backlash.  Any opinions on that?  I had planned on putting my motor on the other side of the gearbox but I can see some advantages of not doing it that way.


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## alan856

Well - good luck on the planning/debugging!  I've been doing tech & software for 40 years, and had my first "inspiration" in  1984 for what I called an "Electronic Gear Box".  I had a Sheldon 10" lathe at the time, and  the world of tech had not advanced enough to make building such a control within my reach.  In 2013 I began dinking with the Arduino family and was hot in pursuit of my EGB dream.  Turns out the math of replacing the gear reduction from the spindle-to-leadscrew to get the needed thread turning ration was a BUGGER!  Perhaps you are more math-inclined...  But you won't be "making chips" any time soon!  I highly encourage you to d/l the ELS4 manual (English too!) and go over all that it does.  At the least this would give you a bit of a road-map as to what you will need to do.

Louis (maker of ELS4) has a lot of info on his site about NOT using ratios from stepper to leadscrew. I will enclose 3 images of my leadscrew hookup.  I did NOT want the usual thing where the motor sticks out way to the left...  I'll put the whole pix series up shortly, but these will give you an idea.  I modded the lathe as little as possible - but did need to chop up the gearbox cover for the motor to fit... mostly a cosmetic change.  That is a 400 PPI encoder (recommended by Louis) and I tried to tie it all into the existing gearbox setup.  Overall - it seems to work VERY well - but running a lathe this way is a HUGE paradigm shift you are skilled/experienced at manually "running the dials" to do your cuts.

More later...  

=A.


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## Reddinr

alan856 said:


> Well - good luck on the planning/debugging!  I've been doing tech & software for 40 years, and had my first "inspiration" in  1984 for what I called an "Electronic Gear Box".  I had a Sheldon 10" lathe at the time, and  the world of tech had not advanced enough to make building such a control within my reach.  In 2013 I began dinking with the Arduino family and was hot in pursuit of my EGB dream.  Turns out the math of replacing the gear reduction from the spindle-to-leadscrew to get the needed thread turning ration was a BUGGER!  Perhaps you are more math-inclined...  But you won't be "making chips" any time soon!  I highly encourage you to d/l the ELS4 manual (English too!) and go over all that it does.  At the least this would give you a bit of a road-map as to what you will need to do.
> 
> Louis (maker of ELS4) has a lot of info on his site about NOT using ratios from stepper to leadscrew. I will enclose 3 images of my leadscrew hookup.  I did NOT want the usual thing where the motor sticks out way to the left...  I'll put the whole pix series up shortly, but these will give you an idea.  I modded the lathe as little as possible - but did need to chop up the gearbox cover for the motor to fit... mostly a cosmetic change.  That is a 400 PPI encoder (recommended by Louis) and I tried to tie it all into the existing gearbox setup.  Overall - it seems to work VERY well - but running a lathe this way is a HUGE paradigm shift you are skilled/experienced at manually "running the dials" to do your cuts.
> 
> More later...
> 
> =A.


Roughly the same background for me.  I have done quite a bit of embedded firmware and am comfortable with the math.  I have been in the "thinking about it" stage for a couple of years now.   I did download the ELS4 manual and will read it in the next day or two.  Thanks for the pictures!


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## GreatOldOne

Baby steps, but it‘s alive!





Your browser is not able to display this video.


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## Briney Eye

Qtron said:


> Clearly my perspective is wrong then, I am thinking here if wear forces on the brass (mine) 1/2 nuts & on smallish HSS threading tool that has to put up with lateral carriage forces and the rotational force of stock being cut/threaded. Wonder what that would be for 2'' dia, CS1020 steel, 20 thou cut for 8 tpi?!


Well, if I understand Machinery's Handbook (which I probably don't), 0.02 depth and 0.02 feed rate at 100fpm (carbon steel) is removing right at 0.5 cubic inches of metal per minute, and that translates into about 0.4hp at the motor if you're using a sharp tool on a belt drive machine.

Addendum: With an electronic leadscrew that will be divided between the spindle motor and the feed motor.


----------



## Briney Eye

Qtron said:


> No probably no diff cos with 1.8° steppers, 400 is 1/2 stepping, 800 is 1/4 stepping, but u will see diff say at full tilt, 1/16th steps vs 1/2. (Should also see a torque diff between full steps & 1/8th stepping rate too).


The motor that I'm using is actually from www.omc-stepperonline.com, since it was shorter than the one that I got from Banggood and would fit in the available space. I just noticed that they now have a 3.5Nm NEMA24 motor that should fit. I would have to upgrade my power supply, which would probably mean moving to a larger enclosure as well.


----------



## Reddinr

Is there a method or calculator online that can help estimate the feed screw HP requirements?  The force on the tool will be in two axes I think; the radial force that tends to push the tool down and the longitudinal force that pushes the tool away from the headstock.  Only the longitudinal portion of that force would contribute much to the HP / torque needs of the lead-screw motor, correct?  I suppose there is some effect of the radial force too that could increase the frictional force between the ways and the saddle.  This would seem to be tool profile dependent too I would think.


----------



## Briney Eye

Reddinr said:


> Is there a method or calculator online that can help estimate the feed screw HP requirements?  The force on the tool will be in two axes I think; the radial force that tends to push the tool down and the longitudinal force that pushes the tool away from the headstock.  Only the longitudinal portion of that force would contribute much to the HP / torque needs of the lead-screw motor, correct?  I suppose there is some effect of the radial force too that could increase the frictional force between the ways and the saddle.  This would seem to be tool profile dependent too I would think.


I strongly suggest getting a copy of Machinery's Handbook if you don't already have one and reading the section on Machinery Power. That's where I pulled the info from. The power is going to be shared between turning the spindle and moving the tool. I'm going to try to measure the power drawn by each during turning and facing cuts and observe the correlation.


----------



## Briney Eye

Reddinr said:


> Is there a method or calculator online that can help estimate the feed screw HP requirements?  The force on the tool will be in two axes I think; the radial force that tends to push the tool down and the longitudinal force that pushes the tool away from the headstock.  Only the longitudinal portion of that force would contribute much to the HP / torque needs of the lead-screw motor, correct?  I suppose there is some effect of the radial force too that could increase the frictional force between the ways and the saddle.  This would seem to be tool profile dependent too I would think.


Look at the calculators at kennametal.com. You still need Machinery's Handbook.


----------



## Briney Eye

Qtron said:


> Clearly my perspective is wrong then, I am thinking here if wear forces on the brass (mine) 1/2 nuts & on smallish HSS threading tool that has to put up with lateral carriage forces and the rotational force of stock being cut/threaded. Wonder what that would be for 2'' dia, CS1020 steel, 20 thou cut for 8 tpi?!


Ha! Kennametal has a calculator! For 1018 steel, Brinnell hardness of 195, cutting depth .02, feed rate .02, 100sfm, direct belt drive gives 0.35hp at the tool, 0.39hp at the motor, 9.62 foot pounds of torque. So my 0.4hp estimate was pretty darned close.

I've ordered the 3.5Nm motor from stepperonline after looking at these numbers. I think I can rearrange things and squeeze a 350W supply into my enclosure.

Oh, it works in Firefox but not in Chrome.


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## Qtron

Briney Eye said:


> Ha! Kennametal has a calculator! For 1018 steel, Brinnell hardness of 195, cutting depth .02, feed rate .02, 100sfm, direct belt drive gives 0.35hp at the tool, 0.39hp at the motor, 9.62 foot pounds of torque. So my 0.4hp estimate was pretty darned close.
> 
> I've ordered the 3.5Nm motor from stepperonline after looking at these numbers. I think I can rearrange things and squeeze a 350W supply into my enclosure.
> 
> Oh, it works in Firefox but not in Chrome.


- Not sure how CS1020 compares w 1018 BH 195..

( i used a simple calc, http://www.discount-tools.com/sfm.htm), so @ 100sfm, stock 2" dia = 191 RPM, if i understand your fig's. correctly then.
So thats 0.35HP rotational power on the tool .. amazing what such a small cross-section of HSS puts up with!! The next Q would be the leadscrew h.p. required and axial forces in that same set of figures..

Thankyou Very Much for your clear insight, time etc, & i /others look fwd to final results, both with the force gauge measurements results, the final gearing, & the average & peak power supply requirements too.

 I guess there will be a compromise in the end, re how fast & deep cuts can be made in worst case materials vs lathe tolerance to such. I just dont wanna put your previously quoted 1100 lb axial force on my 8 TPI leadscrew, bearings, 1/2 nuts, regardless of job demands! (maybe i already unwittingly have).
Have bookmarked the Kennametal Calc., Thanks


----------



## Qtron

Briney Eye said:


> The motor that I'm using is actually from www.omc-stepperonline.com, since it was shorter than the one that I got from Banggood and would fit in the available space. I just noticed that they now have a 3.5Nm NEMA24 motor that should fit. I would have to upgrade my power supply, which would probably mean moving to a larger enclosure as well.


i got bit by a local supplier of steppers, 3 duds sitting here basically useless. The new business owners cant rebate me, but admit they were impossible to drive, & no longer sell them.
Reason is because the Inductive reactance, is way too hi, & the mechanical resonance was aweful to boot. 
The Inter-winding capacitance was also hi.

 The new ones from Stepperonline are 1/3 of the orig at XL~2,5 ohms.
XL=2pi x freq x L, so the higher the stepper rate, the greater the inductive reactance, or more simply, the impedance at that frequency. 
Anything over 180 RPM at full step rate, & those ****ty motors clagged out.
The new ones driven at full step, (so non-sinusoidally driven), stall after 1500 rpm, a big difference. Thats, no mechanical load, No mid band resonance tuning, which evidenced itself at about 950 rpm, from memory.
Alos,
Sometimes a heavy steel disc (damper) is clamped onto the stepper shaft to dampen the resonance, the downside is the accel/decel rate needs to be tempered accordingly. It also helps if a heavy-ish steel plate is fixed securely to the steeper body to help dampen this resonance.
BTW, A rubber mount method should never be used!


----------



## Qtron

GreatOldOne said:


> Baby steps, but it‘s alive!


Is that a galvanised steel mounting plate the goodies are bolted to, GreatOldOne?


----------



## Qtron

alan856 said:


> .. NOT using ratios from stepper to leadscrew..


i presume a grunty servo or perhaps a closed loop Nema 34 stepper is required then?  i like your trick of stabilising the encoder with the now obsolete gear arm (sorry the correct term evades me). And in my shop everything is so tight - a protruding motor would be a real issue, well done!


----------



## Briney Eye

Qtron said:


> i got bit by a local supplier of steppers, 3 duds sitting here basically useless. The new business owners cant rebate me, but admit they were impossible to drive, & no longer sell them.
> Reason is because the Inductive reactance, is way too hi, & the mechanical resonance was aweful to boot.
> The Inter-winding capacitance was also hi.
> 
> The new ones from Stepperonline are 1/3 of the orig at XL~2,5 ohms.
> XL=2pi x freq x L, so the higher the stepper rate, the greater the inductive reactance, or more simply, the impedance at that frequency.
> Anything over 180 RPM at full step rate, & those ****ty motors clagged out.
> The new ones driven at full step, (so non-sinusoidally driven), stall after 1500 rpm, a big difference. Thats, no mechanical load, No mid band resonance tuning, which evidenced itself at about 950 rpm, from memory.
> Alos,
> Sometimes a heavy steel disc (damper) is clamped onto the stepper shaft to dampen the resonance, the downside is the accel/decel rate needs to be tempered accordingly. It also helps if a heavy-ish steel plate is fixed securely to the steeper body to help dampen this resonance.
> BTW, A rubber mount method should never be used!


Stepperonline is selling mostly Leadshine, I think. That's the logo on the motor that I bought from them, and I noticed that they explicitly say that their driver is designed in-house and built by Leadshine. I've got one of their CL57T drivers, but wound up using the HBS57 that I got from Banggood because it runs quieter and cooler. I tried tuning the CL57T and may try it again to get a better handle on what the different parameters do, but the HBS57 just worked without fiddling with it.

I tweak the step rate in my code to mitigate resonances and it has worked pretty well. It's been almost silent at lower rpm's, and only whines a little at higher speeds. We'll see what happens with the new ratios and motor.

I also just noticed that Stepperonline has a new CL57Y driver (in Hot Rod Red) with "a new generation of 32-bit DSP control technology" that I probably would have ordered with the motor if I'd noticed it sooner.


----------



## GreatOldOne

Qtron said:


> Is that a galvanised steel mounting plate the goodies are bolted to, GreatOldOne?



It was purchased from the local DIY shed. It didn’t specifically mention that is was galvanised, just 1mm thick and yay big. I needed something to mount all the goodies to, as the plastic box didn’t have a real backplane to speak of. Just some grooved ridges for screws. All the main parts bar the launchpad are fixed in place with rivnuts and M4 screws, the launchpad has some m3 plastic standoffs. The mounting plate is anchored in the box with M3 self taping cap heads.


----------



## RJSakowski

I got my hybrid stepper and driver in yesterday along with the Omron encoder.  The stepper is from StepperOnline and is their 24HS40-5840-E1000 with 4.25 N-m holding  torque, 24-48 volt, 6 amp.  The question that I am facing is what is an appropriate power supply.  StepperOnline recommended a 250W 36volt switching supply but that seems a little light to me.


----------



## Briney Eye

RJSakowski said:


> I got my hybrid stepper and driver in yesterday along with the Omron encoder.  The stepper is from StepperOnline and is their 24HS40-5840-E1000 with 4.25 N-m holding  torque, 24-48 volt, 6 amp.  The question that I am facing is what is an appropriate power supply.  StepperOnline recommended a 250W 36volt switching supply but that seems a little light to me.


I see that they list their 350W 48V supply with the motor, and I think that I would want the extra headroom. My 2Nm Nema 23 stepper setup seems to "behave" better with a 36V supply, but I don't know what will happen when I switch it to a 3.5Nm Nema 24 motor and a 350W supply.


----------



## whitmore

Reddinr said:


> Is there a method or calculator online that can help estimate the feed screw HP requirements?


If you use the wrong drill on brass, the problem isn't feed pressure, it's feed TENSION as the drill
tries to dig in.   So, feed pressure (like from the feed screw) will depend strongly on tool geometry,
and material being worked.   Torque will be proportional to pressure, with some friction added.
If your tool is a grinding wheel, the expected applied pressure will be near zero.

It might be prudent to analyze the feed-motor power and adjust cut depth (rather than 
hit the limit and stall, which could ruin a workpiece).


----------



## Flyinfool

36 volts at 6A equals 216 watts, so the 36V 250W PS would be adequate.
48V at 6A equals 288 watts, so a 48 V 350W will also get the job done.
To figure watts it is volts times amps equals watts.

48V will get more motor torque that 36V.


----------



## Qtron

Briney Eye said:


> Stepperonline is selling mostly Leadshine, I think. That's the logo on the motor that I bought from them, and I noticed that they explicitly say that their driver is designed in-house and built by Leadshine. I've got one of their CL57T drivers, but wound up using the HBS57 that I got from Banggood because it runs quieter and cooler. I tried tuning the CL57T and may try it again to get a better handle on what the different parameters do, but the HBS57 just worked without fiddling with it.
> 
> I tweak the step rate in my code to mitigate resonances and it has worked pretty well. It's been almost silent at lower rpm's, and only whines a little at higher speeds. We'll see what happens with the new ratios and motor.
> 
> I also just noticed that Stepperonline has a new CL57Y driver (in Hot Rod Red) with "a new generation of 32-bit DSP control technology" that I probably would have ordered with the motor if I'd noticed it sooner.


CL57Y sounds good but flaws may not show up for a while (if any). Will keep in mind, Thanks! Not sure what U mean by ''tweek the step rate in my code to mitigate..'' - normally the stepper is tuned in with the driver, which sometimes comes with a tuning software tool as per the CL57Y.
Does that mean, when U release the code, that users will have to tweek (if no software tool avail)? [technophobia is starting to show-eh!]
FYI, the pdf for their manual is a dud link: https://www.omc-stepperonline.com/download/CL57Y.pdf


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## RJSakowski

Thanks Briney, Flyinfool;

I wasn't certain as to whether the quoted current spec. was per winding or total current.  In my past experience, it has been the latter. I also don't know what the relationship is between winding current and power supply draw.  Additionally, my concern is the ability of a switching supply to handle current surges and back voltage spikes. I had read that linear supplies were preferred for that reason.   When excess current is demanded from a linear supply, the voltage just drops.  A switching supply will error out.  Back voltages on a transformer/diode bridge/capacitor supply are absorbed by the capacitor.  How does a switching supply handle them?

I'm leaning towards the 400W 48 volt supply. There is about 20% more available  torque at speeds above 200RPM over a 36 volt supply.  The 20% extra current capacity won't hurt either.


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## homebrewed

All power supplies, switcher or linear, have some capacitors across their outputs.  Passive filtering is the way to go to ensure low output impedance at higher frequencies (which is a Good Thing for a PSU to possess).  However, switchers may have smaller caps compared to linears.  So what's wrong with adding your own capacitors to the switcher output?  The current needed to charge them might cause the switcher to error out; but maybe not, because the charging current is directly related to how fast the switcher's output can ramp up:  I = C*dv/dt, where dv/dt is the output ramp rate.

To handle large transient current demands the outboard caps have to be fairly large values, but certainly no larger than what a linear would have.  And you still avoid the added size and weight of the linear's transformer.

Hanging caps on the output of a switcher should NOT cause it to become unstable, because all electronics have power supply bypass capacitors in them anyway.  So that's not the issue, it's whether or not the supply will complain about the initial charging current.


----------



## GreatOldOne

It’s ALLLLLLLLIVE! 






I’ve added a small 80mm fan to draw air in at the bottom. The blue light is a buck convector stepping down the 24v supply to 12v.









All the connectors are of the locking type. I had to get a larger, 16mm connector for the servo encoder, as the cable diameter was to great for the shell. I’ve added some vents to the top of the case to allow hot air out. 3D printed grills from thingiverse, as was the fan grill on the front.








Flashed the board with James’s firmware, and fingers crossed:




Your browser is not able to display this video.




















It works! Yay. Happy dance ensue.


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## Briney Eye

Qtron said:


> CL57Y sounds good but flaws may not show up for a while (if any). Will keep in mind, Thanks! Not sure what U mean by ''tweek the step rate in my code to mitigate..'' - normally the stepper is tuned in with the driver, which sometimes comes with a tuning software tool as per the CL57Y.
> Does that mean, when U release the code, that users will have to tweek (if no software tool avail)? [technophobia is starting to show-eh!]
> FYI, the pdf for their manual is a dud link: https://www.omc-stepperonline.com/download/CL57Y.pdf


Since the CL57Y has a USB rather than the "standard" RJ connector I'll be waiting for the manual to actually become available before I think about buying one. A USB connector ought to mean a USB interface, right? 

I have a small lookup table that makes adjustments to the PWM period according to the number of steps output per spindle count. I was able to mitigate some small resonances that way and have less stepper whine. I actually started off dynamically varying the period according to RPM, but that introduces its own resonances. My results were pretty good with the simpler scheme so I went with that. I may be revisiting it. I've been pondering a "spread spectrum" scheme, but it already kind of does that just because of the nature of distributing the steps per spindle count for a given rate. We shall see.


----------



## eurofox

Hi,

Here is my version of use of ELS on an Emco 8 lathe.

I can still use my lathe manually with a DRO
I can use my lathe as an CNC lathe with Mach3
I can use an advanced ELS with many features:
 Gearbox Left
 Gearbox Right
 Turning
 Boring
 Facing
 Parting
 Ext Thread
 Int Thread
 Ext Thread <0
 Ext Taper
 Int Taper
 Ext Radius )
 Ext Radius (
 Int Radius )
 Int Radius (
 Grinding
 Angle
 Settings

Have a nice day


----------



## Qtron

Wow, Eurofox, sounds very slick, any details re controller?
Arduino based or commercial off the shelf?


----------



## eurofox

I use the ELS system from Rocketronics and a genereric USB Mack3 4 axis + spindle with VFD interface.
You will find here on a French machinist forum more detail, you can use Google translator.
The ELS allow to "free" the steppers, this way is easy to use the lathe in the manual mode with a DRO.


----------



## Qtron

eurofox said:


> I use the ELS system from Rocketronics and a genereric USB Mack3 4 axis + spindle with VFD interface.
> You will find here on a French machinist forum more detail, you can use Google translator.
> The ELS allow to "free" the steppers, this way is easy to use the lathe in the manual mode with a DRO.


Oh, thought it was your design, couldn't tell from photo. So I assume ELS4? (Big $$ landed here, Oz)


----------



## GreatOldOne

Designed and printed some parts to fit the encoder to the spindle:






Mounting consists of a bracket, spindle / shaft coupler and a stud that is threaded to screw into an existing mounting hole (it used to have a cap head that helps hold the side of the gear box case to the headstock)














Here's STLs & STEP files on thingiverse... it might be of help to other SC4 owners (usual caveats apply - just because they fit my lathe, doesn't mean to say it will fit all SC4s)









						Spindle Encoder Mount and Coupling by GreatOldOne
					

A bracket and coupling to mount an Omron rotary encoder on the spindle of my SIEG SC4 lathe, for use with the Clough42 ELS system. The coupler is 16mm to 6mm, with a 4mm keyway for the larger shaft, and a hole for a 3mm set screw to secure the smaller shaft. Bracket uses a 1/2" stud that...




					www.thingiverse.com


----------



## Qtron

GreatOldOne said:


> Designed and printed some parts to fit the encoder to the spindle:
> (pics clipped)
> Mounting consists of a bracket, spindle / shaft coupler and a stud that is threaded to screw into an existing mounting hole (it used to have a cap head that helps hold the side of the gear box case to the headstock)
> 
> 
> 
> 
> 
> Here's STLs & STEP files on thingiverse... it might be of help to other SC4 owners (usual caveats apply - just because they fit my lathe, doesn't mean to say it will fit all SC4s)
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Spindle Encoder Mount and Coupling by GreatOldOne
> 
> 
> A bracket and coupling to mount an Omron rotary encoder on the spindle of my SIEG SC4 lathe, for use with the Clough42 ELS system. The coupler is 16mm to 6mm, with a 4mm keyway for the larger shaft, and a hole for a 3mm set screw to secure the smaller shaft. Bracket uses a 1/2" stud that...
> 
> 
> 
> 
> www.thingiverse.com


Very nice work bro., the Prusa i3 Mk3 any issues? jams? what material ? heard that there's a new printable material out that's 4 x tougher than ABS!


----------



## GreatOldOne

Qtron said:


> Very nice work bro., the Prusa i3 Mk3 any issues? jams? what material ? heard that there's a new printable material out that's 4 x tougher than ABS!



Its a good printer, with loads of support from an active community. I have had jams in the past, but not had any recently. Those parts are printed in PETG. It’s like a half way house between ABS and PLA. Easy to print, but stronger and UV stable.


----------



## RJSakowski

I have collected all of the components for my ELS with the exception of the drive belt for the encoder and the machining is completed except for mounting the encoder bracket. 

The NEMA 24 stepper fit nicely in the opening at the base of my G0602 lathe. A 130 to 136 tooth belt will work in this position.   Rather than machine the flanges of the GT2 drive pulley as Clough42 did, I counterbored the pulley to accept the e clip.




	

		
			
		

		
	
.......
	

		
			
		

		
	





Time to start on the electronics.  I resurrected my ESD mat and am ready to assemble and test the circuitry.

I have one question for the group.  I have elected to go with a 1:1 drive for the stepper and will need to change the 3:1 ratio.  I am having trouble locating where the stepper pulley ratio is defined in the source code.  If anyone can direct me, I would appreciate it.


----------



## kb58

Watch Part 2 for how he works out the numbers. I'm facing the same issue, made more fun by the additional reduction inside my QCGB.


----------



## RJSakowski

kb58 said:


> Watch Part 2 for how he works out the numbers. I'm facing the same issue, made more fun by the additional reduction inside my QCGB.


The correct ratio could be set by changing the lead screw pitch.  Since I am driving at 1:1 (same lathe) and James is driving at 3:1, my lead screw will turn at 3x his.  If I set the lead screw pitch at 36 tpi, , it will advance 1/3rd as far for each revolution and all should be good.  However, this seems a kludgy way to do it.

I know that James ran 1:1 when he ran the stepper and he talked about possibly running other ratios to optimize so I suspect he has a variable for that ratio.


----------



## ttabbal

I haven't looked at the latest code version, but the one I looked at had a steps per rev value. I think that's what you use to adjust for the ratio.

I haven't gotten the stepper mounted yet, so I could be off there.


----------



## GreatOldOne

USB socket added to the control box for easy firmware upgrades. Servo / Hybrid stepper mounted, Control box hung on the back of the lathe, change gear cover modified to fit over the encoder and servo. Oh, and wired in so it all turns on when the lathe is switched on.


































What I have encountered whilst testing is I can quite easily get the driver alarm to trigger... depending on spindle speed and thread pitch / feed selected. My lathe has a top speed of 2000rpm, and with the pulley ratio of 3:1 and then whatever the multiplier is for feed - you can quite easily top out the max RPM of the servo. I've just made a chart of max possible spindle speed for a given feed. For the most part, the feeds are fine. it's the thread pitches that can make it go down... but I very much doubt I'd ever need to do any single point threading above a couple of hundred RPM anyway. And the convenience of not having to bugger about with change gears far outweighs the possible need to do a 5 TPI thread at over 1000RPM


----------



## GreatOldOne

RJSakowski said:


> I have one question for the group.  I have elected to go with a 1:1 drive for the stepper and will need to change the 3:1 ratio.  I am having trouble locating where the stepper pulley ratio is defined in the source code.  If anyone can direct me, I would appreciate it.





kb58 said:


> Watch Part 2 for how he works out the numbers. I'm facing the same issue, made more fun by the additional reduction inside my QCGB.





RJSakowski said:


> The correct ratio could be set by changing the lead screw pitch.  Since I am driving at 1:1 (same lathe) and James is driving at 3:1, my lead screw will turn at 3x his.  If I set the lead screw pitch at 36 tpi, , it will advance 1/3rd as far for each revolution and all should be good.  However, this seems a kludgy way to do it.
> 
> I know that James ran 1:1 when he ran the stepper and he talked about possibly running other ratios to optimize so I suspect he has a variable for that ratio.





ttabbal said:


> I haven't looked at the latest code version, but the one I looked at had a steps per rev value. I think that's what you use to adjust for the ratio.
> 
> I haven't gotten the stepper mounted yet, so I could be off there.



Guys - the ratio of stepper to leadscrew pulleys is handled by the micro step value in the config file. It took me a while to work this out and find the video where he explains it again... but if you’re using a hybrid stepper / servo you’re supposed to set this to 1, as they don’t micro step. But he sets his to 3 micro steps as this takes care of the 3:1 ratio he has - as it essentially triples the number of steps sent to the motor.

When I first flashed the firmware to the board and started testing I couldn’t work out why it was turning so slowly... until I realised that it was set to 1:1 rather than 3:1 as I have the same pulley ratio as James. After changing that it seems to be dead on now. Test cuts will show if thats true.


----------



## kb58

Another issue is whether the lathe's gearbox reverses rotation of the lead screw. If so, the servo driver box may have a way to correct that. If not, it means modifying the ELS software.


----------



## RJSakowski

GreatOldOne said:


> Guys - the ratio of stepper to leadscrew pulleys is handled by the micro step value in the config file. It took me a while to work this out and find the video where he explains it again... but if you’re using a hybrid stepper / servo you’re supposed to set this to 1, as they don’t micro step. But he sets his to 3 micro steps as this takes care of the 3:1 ratio he has - as it essentially triples the number of steps sent to the motor.
> 
> When I first flashed the firmware to the board and started testing I couldn’t work out why it was turning so slowly... until I realised that it was set to 1:1 rather than 3:1 as I have the same pulley ratio as James. After changing that it seems to be dead on now. Test cuts will show if thats true.


Great Old One, thanks for that insight.  I am using a 1:1 ratio with a hybrid stepper so it sounds like I don't need to make a change.


----------



## GreatOldOne

kb58 said:


> Another issue is whether the lathe's gearbox reverses rotation of the lead screw. If so, the servo driver box may have a way to correct that. If not, it means modifying the ELS software.



My servo driver has dip switch settings to set the initial rotation direction. I thought I might have to mess with it as the spindle on my lathe is fed by the shaft the encoder is on via a 1:1 spur gear setup deeper in the head stock - so it spins in the opposite direction to the encoder. Seems I lucked out though.


----------



## GreatOldOne

i completed my install with a 3d printed bracket which holds the ELS controls under my DRO display. I designed it to be offset so the cable wouldn’t interfere with the DRO mount, and to pick up the existing mounting holes in the DRO case.









Maybe I can get back to using my lathe now rather than modifying it!


----------



## ttabbal

Nice job! I might have to think about mounting the controls to the DRO display as well. I hadn't considered that.


----------



## kb58

GreatOldOne said:


> i completed my install with a 3d printed bracket which holds the ELS controls under my DRO display. I designed it to be offset so the cable wouldn’t interfere with the DRO mount, and to pick up the existing mounting holes in the DRO case.
> 
> View attachment 306642
> 
> 
> Maybe I can get back to using my lathe now rather than modifying it!


Curious how you power the ELS. Is there a separate power switch, or is it on whenever the lathe is powered up? I'm thinking of having both, basically a switch downstream of the lathe breaker dedicated to the ELS.

Edit - which reminds me, I found that the "power" button on the ELS doesn't do anything. I'm guessing that it'll flip an output bit intended to drive a relay. I'd be happy if it just disabled driving the servo, because there's no point in running it if not needed. Easy enough to modify it myself I guess...


----------



## GreatOldOne

kb58 said:


> Curious how you power the ELS. Is there a separate power switch, or is it on whenever the lathe is powered up? I'm thinking of having both, basically a switch downstream of the lathe breaker dedicated to the ELS.



The SC4 has a IEC socket on the back of the headstock. It’s there to provide mains power whenever the lathe is turned on for an optional milling head. As I don’t have that, I’m using it to power both the DRO and the ELS. I can switch either of those off As the ELS has a switched power I out socket, and the DRO has a power switch on the back of the display.


----------



## GreatOldOne

So, in a shocking turn of events, it actually does what it’s advertised to. 

Quick and dirty M12 x1.75.








Things to note:


My lathe has a metric leadscrew, 2mm pitch
Due to this (and the lack of a thread dial) I need to keep the leadscrew engaged all the time and reverse the lathe at the end of the cut
Stopping the lathe when you get to the lead out trough is something I’m going to have to get use to as the lathe doesn’t slow down as quickly as it did with all the change gears.


----------



## RJSakowski

GreatOldOne said:


> So, in a shocking turn of events, it actually does what it’s advertised to.
> 
> Quick and dirty M12 x1.75.
> View attachment 306671
> View attachment 306672
> 
> Things to note:
> 
> 
> My lathe has a metric leadscrew, 2mm pitch
> Due to this (and the lack of a thread dial) I need to keep the leadscrew engaged all the time and reverse the lathe at the end of the cut
> Stopping the lathe when you get to the lead out trough is something I’m going to have to get use to as the lathe doesn’t slow down as quickly as it did with all the change gears.


Take a look at Tom Lipton, OxToolsn for a solution to stopping the lathe when you reach the lead out trough on metric threading.


----------



## RJSakowski

I have the Launchpad up and running and I am having a problem deciding what the proper parameter settings are.  I am using a SteppersOnline hybrid stepper driver, CL57T, which appear to be a clone of the the Leadshine ES-D508 driver.  However, Clough42 used a KL-5080H driver.  One obvious difference is that his driver has no microstep setting switches whereas the other two do.  

It appears that I should be daisy chaining the + inputs and connecting PUL-, DI-, and EN- leads to their respective driver inputs.  It also appears that the STEP and DIRECTION logic should be left active high while the ENABLE and ALARM logic should be active low.

I am also guessing that I should be setting my MICROSTEPS to 8 and my RESOLUTION to 200 to match my selection on the drive.

Any guidance will be greatly appreciated.

links to the three manuals:


			https://www.automationtechnologiesinc.com/wp-content/uploads/downloads/2012/06/KL-5080H.pdf
		



			https://www.omc-stepperonline.com/download/CL57T.pdf
		



			http://www.americanmotiontech.com/upload/HardwareInstallation/ES-Dhm_V1.1.pdf


----------



## GreatOldOne

RJSakowski said:


> I have the Launchpad up and running and I am having a problem deciding what the proper parameter settings are.  I am using a SteppersOnline hybrid stepper driver, CL57T, which appear to be a clone of the the Leadshine ES-D508 driver.  However, Clough42 used a KL-5080H driver.  One obvious difference is that his driver has no microstep setting switches whereas the other two do.
> 
> It appears that I should be daisy chaining the + inputs and connecting PUL-, DI-, and EN- leads to their respective driver inputs.  It also appears that the STEP and DIRECTION logic should be left active high while the ENABLE and ALARM logic should be active low.
> 
> I am also guessing that I should be setting my MICROSTEPS to 8 and my RESOLUTION to 200 to match my selection on the drive.
> 
> Any guidance will be greatly appreciated.
> 
> links to the three manuals:
> 
> 
> https://www.automationtechnologiesinc.com/wp-content/uploads/downloads/2012/06/KL-5080H.pdf
> 
> 
> 
> 
> https://www.omc-stepperonline.com/download/CL57T.pdf
> 
> 
> 
> 
> http://www.americanmotiontech.com/upload/HardwareInstallation/ES-Dhm_V1.1.pdf



 Reading the CL57T manual, I’d set the driver to 1000: 





as I believe the term microstep is being used interchangeably. I reckon this is the steps per revolution. Then in configuration.h set the steps to 1000, and the micro steps to the ratio of pulleys being used (I like James have 3:1 so I set mine to 3).

Try it out At low speed and check your movement.


----------



## RJSakowski

RJSakowski said:


> It appears that I should be daisy chaining the + inputs and connecting PUL-, DI-, and EN- leads to their respective driver inputs.  It also appears that the STEP and DIRECTION logic should be left active high while the ENABLE and ALARM logic should be active low.
> 
> I am also guessing that I should be setting my MICROSTEPS to 8 and my RESOLUTION to 200 to match my selection on the drive.
> 
> A


I connected everything together and powered up.  With connections and parameters set as above, the system works and at 12 tpi it tracks 1:1 as it should.  Spinning the encoder by hand, I lost steps at something over 1000 rpm.  Spinning at over 450 rpm, I still tracked. 12.tpi is .0833"/rev and at 1000 rpm, that is 83 ipm.which is moving fairly fast.  Clough42 has set the upper limit for feed at .040"/rev. so everything looks good so far.

I will have to wait for a more precise test until I have the encoder mounted on the lathe.  

On to enclosures as I wait for the encoder belt.


----------



## Qtron

GreatOldOne said:


> So, in a shocking turn of events, it actually does what it’s advertised to.
> 
> Quick and dirty M12 x1.75.
> View attachment 306671
> View attachment 306672
> 
> Things to note:
> 
> 
> My lathe has a metric leadscrew, 2mm pitch
> Due to this (and the lack of a thread dial) I need to keep the leadscrew engaged all the time and reverse the lathe at the end of the cut
> Stopping the lathe when you get to the lead out trough is something I’m going to have to get use to as the lathe doesn’t slow down as quickly as it did with all the change gears.


Your enthusiasm inspires! well done indeed. A VFD brake would solve your stopping issue. Some VFD's inject DC into the field coils.. stops DEAD fast.
- hey did U make the collect chuck? if not where buy U?


----------



## RJSakowski

I would be concerned about a sudden spindle stop or reversal of direction causing high back emf in the stepper and triggering a driver error.


----------



## GreatOldOne

Qtron said:


> - hey did U make the collect chuck? if not where buy U?



it was an eBay purchase. One of the ubiquitous Chinese 5c chucks out there. I turned the back plate though.


----------



## Qtron

GreatOldOne said:


> it was an eBay purchase. One of the ubiquitous Chinese 5c chucks out there. I turned the back plate though.


Ah will get one then,  - making a backing plate one needs an ELS, well, at least for a threaded spindle. Cam lock poses more problems I suppose (never used one).


----------



## Qtron

RJSakowski said:


> I would be concerned about a sudden spindle stop or reversal of direction causing high back emf in the stepper and triggering a driver error.


Agree, RJ. 
Another alternative, as you probably know,
But for the sake if others,
A less vicious brake can be a VSD braking power resistor. The higher the value, the slower the wind down, particularly towards the last few revs as the little amount of energy generated has a very small residual field current, - all assuming V bus is disconnected in the VSD (Coasting mode).
Well, that's my understanding of the brake mechanism.
DC injection is usually on bigger machines w very high inertial loads.


----------



## RJSakowski

I received my encoder belt on Monday; the last item on my BOM.  However, I also had carpal tunnel surgery that day and had to delay  the mounting of the encoder.  I managed to get the encoder mounted and connected everything together for a test run.  I was disappointed in the available torque.  I expected more from a 600 oz.-in stepper. Running the spindle at 175 rpm and the 12 tpi lead screw at .125"/rev. (8 tpi) , the stepper was turning at 262 rpm.  I could make the motor lose steps with 40 lbs. of force applied to the carriage.  I tried cutting a 7/16 -14 tpi thread and was able to cut the thread although the motor encoder kicked in to make up lost steps. 

One obvious improvement would be to increase the supply voltage.  I am running a 36 volt supply and the drive is capable of handling 48 volts. From the torque curve, this would give me about 20 - 30% more torque. A simple experiment would be to use the 602 gear box to do a 2:1 reduction, doubling the torque.  This would be similar to Clough42's 3:1 motor pulley ratio.  The concern is that the stepper motor has a relatively flat torque x rpm curve so very little is gained by using pulleys.





Here is that curve for my motor, running at 36 volts, derived from the published specs.

Another possible issue is driver tuning.  Supposedly, the driver has an autotune feature but this may be making compromises for torque for the sake of other features.  StepperOnline is secretive about the tuning software but others have suggested that Leadshine's tuning software is the one to use.  I'll have to make up the serial cable.  It's been a long time since I've done any work with RS232 cables but as I recall, only RX, TX, and GND are needed and the RX and TX lines are crossed.  (Someone please correct me if I'm wrong.)

I am using a setting of 1600 steps/rev on the driver and 200 steps and 8 microsteps in the Clough42 software.  This gives me the correct spindle to lead screw ratio.  However, other have used the motor encoder resolution of 1000 pulses in setting the driver and in the controller software.  Is there possibly an impact on torque there?

As I recall, a stepper has its best torque output at full step positions.  Would there be an advantage to decreasing the number of microsteps?  So many questions to answer.


----------



## Qtron

Qtron said:


> Agree, RJ.
> Another alternative, as you probably know,
> But for the sake if others,
> A less vicious brake can be a VSD braking power resistor. The higher the value, the slower the wind down, particularly towards the last few revs as the little amount of energy generated has a very small residual field current, - all assuming V bus is disconnected in the VSD (Coasting mode).
> Well, that's my understanding of the brake mechanism.
> DC injection is usually on bigger machines w very high inertial loads.


Both methods cause extra motor heating which with repetitive stopping, can become a problem


RJSakowski said:


> I received my encoder belt on Monday; the last item on my BOM.  However, I also had carpal tunnel surgery that day and had to delay  the mounting of the encoder.  I managed to get the encoder mounted and connected everything together for a test run.  I was disappointed in the available torque.  I expected more from a 600 oz.-in stepper. Running the spindle at 175 rpm and the 12 tpi lead screw at .125"/rev. (8 tpi) , the stepper was turning at 262 rpm.  I could make the motor lose steps with 40 lbs. of force applied to the carriage.  I tried cutting a 7/16 -14 tpi thread and was able to cut the thread although the motor encoder kicked in to make up lost steps.
> 
> One obvious improvement would be to increase the supply voltage.  I am running a 36 volt supply and the drive is capable of handling 48 volts. From the torque curve, this would give me about 20 - 30% more torque. A simple experiment would be to use the 602 gear box to do a 2:1 reduction, doubling the torque.  This would be similar to Clough42's 3:1 motor pulley ratio.  The concern is that the stepper motor has a relatively flat torque x rpm curve so very little is gained by using pulleys.
> View attachment 307253
> 
> Here is that curve for my motor, running at 36 volts, derived from the published specs.
> 
> Another possible issue is driver tuning.  Supposedly, the driver has an autotune feature but this may be making compromises for torque for the sake of other features.  StepperOnline is secretive about the tuning software but others have suggested that Leadshine's tuning software is the one to use.  I'll have to make up the serial cable.  It's been a long time since I've done any work with RS232 cables but as I recall, only RX, TX, and GND are needed and the RX and TX lines are crossed.  (Someone please correct me if I'm wrong.)
> 
> I am using a setting of 1600 steps/rev on the driver and 200 steps and 8 microsteps in the Clough42 software.  This gives me the correct spindle to lead screw ratio.  However, other have used the motor encoder resolution of 1000 pulses in setting the driver and in the controller software.  Is there possibly an impact on torque there?
> 
> As I recall, a stepper has its best torque output at full step positions.  Would there be an advantage to decreasing the number of microsteps?  So many questions to answer.


110,000 oz.INS/sec =776.7707 watts! Acc to a converter, pls check.
 Thats enormous!


----------



## Qtron

Qtron said:


> Both methods cause extra motor heating which with repetitive stopping, can become a problem
> 
> 110,000 oz.INS/sec =776.7707 watts! Acc to a converter, pls check.
> Thats enormous!


Whats the average current draw at 400 rpm?


----------



## RJSakowski

Qtron said:


> Both methods cause extra motor heating which with repetitive stopping, can become a problem
> 
> 110,000 oz.INS/sec =776.7707 watts! Acc to a converter, pls check.
> Thats enormous!


There is actually a unitless factor of 2π, if I am not mistaken, so it more like 120 watts.


----------



## Qtron

RJSakowski said:


> There is actually a unitless factor of 2π, if I am not mistaken, so it more like 120 watts.


Not sure where 2 pi fits in the graph, pls clarify


----------



## RJSakowski

One revolution is 2π radians


----------



## Qtron

RJSakowski said:


> One revolution is 2π radians


----------



## RJSakowski

It actually doesn't as I am simply looking at torque times rpm to determine if there would be a benefit to gearing up or down.  From the graph, it appears that I wouldn't.  The y axis is proportional to power so a flat curve kind of makes sense.


----------



## Qtron

RJSakowski said:


> It actually doesn't as I am simply looking at torque times rpm to determine if there would be a benefit to gearing up or down.  From the graph, it appears that I wouldn't.  The y axis is proportional to power so a flat curve kind of makes sense.


A while back Briney Eye was quoting huge forces on the saddle, 700 lb plus, for 8 tpi threads in harder steels,, He had received a torque gauge but dunno the outcome of measurements.


----------



## kb58

RJSakowski said:


> ...The concern is that the stepper motor has a relatively flat torque x rpm curve so very little is gained by using pulleys...


No, whatever torque the motor develops will be multiplied by the gear ratio, regardless of rpm.


----------



## Qtron

Qtron said:


> A while back Briney Eye was quoting huge forces on the saddle, 700 lb plus, for 8 tpi threads in harder steels,, He had received a torque gauge but dunno the outcome of measurements.


Pulleys would provide torque  below 300 revs on graph?


----------



## RJSakowski

kb58 said:


> No, whatever torque the motor develops will be multiplied by the gear ratio, regardless of rpm.


Right, but a 2:1 increase in torque by virtie of gearing is accompanied by a halving of the motor torque by virtue if the soubling of motor speed to provide the same output rpm.


----------



## Qtron

RJSakowski said:


> Right, but a 2:1 increase in torque by virtie of gearing is accompanied by a halving of the motor torque by virtue if the soubling of motor speed to provide the same output rpm.


Understood


----------



## Qtron

RJSakowski said:


> I received my encoder belt on Monday; the last item on my BOM.  However, I also had carpal tunnel surgery that day and had to delay  the mounting of the encoder.  I managed to get the encoder mounted and connected everything together for a test run.  I was disappointed in the available torque.  I expected more from a 600 oz.-in stepper. Running the spindle at 175 rpm and the 12 tpi lead screw at .125"/rev. (8 tpi) , the stepper was turning at 262 rpm.  I could make the motor lose steps with 40 lbs. of force applied to the carriage.  I tried cutting a 7/16 -14 tpi thread and was able to cut the thread although the motor encoder kicked in to make up lost steps.
> 
> One obvious improvement would be to increase the supply voltage.  I am running a 36 volt supply and the drive is capable of handling 48 volts. From the torque curve, this would give me about 20 - 30% more torque. A simple experiment would be to use the 602 gear box to do a 2:1 reduction, doubling the torque.  This would be similar to Clough42's 3:1 motor pulley ratio.  The concern is that the stepper motor has a relatively flat torque x rpm curve so very little is gained by using pulleys.
> View attachment 307253
> 
> Here is that curve for my motor, running at 36 volts, derived from the published specs.
> 
> Another possible issue is driver tuning.  Supposedly, the driver has an autotune feature but this may be making compromises for torque for the sake of other features.  StepperOnline is secretive about the tuning software but others have suggested that Leadshine's tuning software is the one to use.  I'll have to make up the serial cable.  It's been a long time since I've done any work with RS232 cables but as I recall, only RX, TX, and GND are needed and the RX and TX lines are crossed.  (Someone please correct me if I'm wrong.)
> 
> I am using a setting of 1600 steps/rev on the driver and 200 steps and 8 microsteps in the Clough42 software.  This gives me the correct spindle to lead screw ratio.  However, other have used the motor encoder resolution of 1000 pulses in setting the driver and in the controller software.  Is there possibly an impact on torque there?
> 
> As I recall, a stepper has its best torque output at full step positions.  Would there be an advantage to decreasing the number of microsteps?  So many questions to answer.


Full steps = Max torque, but far more prone to 'mid band resonance'. (Bench tested!).


----------



## Qtron

Qtron said:


> Full steps = Max torque, but far more prone to 'mid band resonance'. (Bench tested!).


A while back Briney Eye was quoting huge forces on the saddle, 700 lb plus, for 8 tpi threads in harder steels,, He had received a torque gauge but dunno the outcome of measurements.


----------



## Qtron

Qtron said:


> A while back Briney Eye was quoting huge forces on the saddle, 700 lb plus, for 8 tpi threads in harder steels,, He had received a torque gauge but dunno the outcome of measurements.


Sorry but still figuring out forum 'syntax' behaviour


----------



## RJSakowski

Qtron said:


> Pulleys would provide torque  below 300 revs on graph?


That can be misleading as the low RPM is pulling down the product.  A theoretical stepper motor would have infinte torque at 0 RPM but in reality, it is limited by electrical characteristics.  Looking at the torque vs. RPM curve, the torque is relatively constant at low rpm.  At .001"/rev power feed @ 625 RPM spindle, the lead screw is only turning at about 8 RPM


Qtron said:


> Full steps = Max torque, but far more prone to 'mid band resonance'. (Bench tested!).


That's what I rememberas well.  I am thinking that the lost steps I am seeing are the happening during the microsteps and the motor feedback corrects for them.


----------



## Qtron

Qtron said:


> Sorry but still figuring out forum 'syntax' behaviour


Try 1/4 steps, sh give better torque, but if 700 lb needed, there's a gulf to be bridged


----------



## Qtron

Qtron said:


> Try 1/4 steps, sh give better torque, but if 700 lb needed, there's a gulf to be bridged


James Clough42 probably has the answer


----------



## Qtron

Qtron said:


> James Clough42 probably has the answer


He did use a servo motor, almost full torque at zero


----------



## RJSakowski

Qtron said:


> He did use a servo motor, almost full torque at zero


The stepper has full torque at zero as well.  Where steppers fall down is at high RPM. Servos have a much flatter torque vs. RPM curve which is why he was able to use a 3:1 pulley to his advantage.  My mistake was thinking that the hybrid stepper that I bought would have a similar curve.  I bought the motor/driver kit  before I found the torque curve.


----------



## Qtron

RJSakowski said:


> The stepper has full torque at zero as well.  Where steppers fall down is at high RPM. Servos have a much flatter torque vs. RPM curve which is why he was able to use a 3:1 pulley to his advantage.  My mistake was thinking that the hybrid stepper that I bought would have a similar curve.  I bought the motor/driver kit  before I found the torque curve.


Oh. Whats the power rating, in watts of the stepper.. stated, (not graph calculated)?
 Really appreciate the graph tho. 
I intend to use a 200 watt 24v skew wound brushed DC motor and tack an AMT102 capacitive encoder on its bum, thus a servo, to drive the leadscrew, thru the lathe gearbox, for more torque, as Briney eye indicates. My lathe is bigger than cloughs, so I reckon I need all the torque I can get, for larger dia coarse threading jobs. Direct to LS mounting of a stepper is ONLY recommended by Rocketronics with their ELS 4, cos - I thinks, they r trying to minimize resonances.


----------



## kb58

Regardless of stepper/servo motor size, at some point we just have to limit how deep a cut we take. The question becomes subjective as to whether that cutting depth is acceptable.


----------



## Briney Eye

I see my name being taken in vain, so here's an update.

I've changed my setup to an 8:1 ratio between my stepper and leadscrew, and have my drive module set to 400 microsteps per rev.  Speed is not an issue since I'm actually generating 20% fewer steps now than I was with a 4:1 drive and 1000 microsteps.  I've been sorting the code out before I swap my 2Nm Nema 23 motor for a 3.5Nm Nema 24 motor.

Changing the ratios and microsteps gave me the incentive to finally become conversant with function-like macros, so I'm a big step closer to calling myself a C programmer.  No more hand-calculating steps when I build the lookup tables.  I'm still avoiding the step to C++ because I really don't see an advantage to all the "syntactical sugar" at this point.

Once I have things sorted out I intend to use my "new" dial force gage to measure just how much mechanical advantage I have.  I hope to post some results in the next few days.  I'm mildly concerned that I have less wrap on the stepper drive pulley with the greater differential in pulley size, but we'll see what happens.  If it's necessary I can make a new motor bracket and incorporate an idler to get more wrap.


----------



## Qtron

Briney Eye said:


> I see my name being taken in vain, so here's an update.
> 
> I've changed my setup to an 8:1 ratio between my stepper and leadscrew, and have my drive module set to 400 microsteps per rev.  Speed is not an issue since I'm actually generating 20% fewer steps now than I was with a 4:1 drive and 1000 microsteps.  I've been sorting the code out before I swap my 2Nm Nema 23 motor for a 3.5Nm Nema 24 motor.
> 
> Changing the ratios and microsteps gave me the incentive to finally become conversant with function-like macros, so I'm a big step closer to calling myself a C programmer.  No more hand-calculating steps when I build the lookup tables.  I'm still avoiding the step to C++ because I really don't see an advantage to all the "syntactical sugar" at this point.
> 
> Once I have things sorted out I intend to use my "new" dial force gage to measure just how much mechanical advantage I have.  I hope to post some results in the next few days.  I'm mildly concerned that I have less wrap on the stepper drive pulley with the greater differential in pulley size, but we'll see what happens.  If it's necessary I can make a new motor bracket and incorporate an idler to get more wrap.


Wrap???


----------



## Qtron

kb58 said:


> Regardless of stepper/servo motor size, at some point we just have to limit how deep a cut we take. The question becomes subjective as to whether that cutting depth is acceptable.


Yep, lighter cuts suggested twice previously, but my post on that didnt draw any fire..


----------



## Qtron

Qtron said:


> Wrap???


Ah, got what u mean,, tooth belt traction around the now smaller stepper pulley


----------



## Qtron

Qtron said:


> Ah, got what u mean,, tooth belt traction around the now smaller stepper pulley


Does anyone have info on the Clough42 setup, does he have enuf torque for deep cuts?


----------



## Qtron

Qtron said:


> Does anyone have info on the Clough42 setup, does he have enuf torque for deep cuts?


Maybe better just to use the lathe as intended? Change gears on mine not too hard to set up, I just have to put up w back gear noise/clatter.
Besides, how many of us are cutting threads all day?


----------



## Briney Eye

Qtron said:


> Maybe better just to use the lathe as intended? Change gears on mine not too hard to set up, I just have to put up w back gear noise/clatter.
> Besides, how many of us are cutting threads all day?


Normal everyday use has not been a problem so far.  I'm taking pretty deep, fast cuts on aluminum with no issues.  The only time I've seen any anomalies is when I was cutting 8tpi Acme threads in 1144 Stressproof with a cheap Chinese carbide insert and it was digging in.  I actually stalled the spindle and slipped the belt a couple of times, which would be no different with change gears.  I took a couple more turns on the belt tension screw and then thought that it hung slightly a couple of times, but didn't stall long enough to error out the stepper drive (which takes a little less than a quarter turn on the motor shaft).  With the belt tightened, the lower ratio and a stouter motor I've got a good feeling about how it will perform, even in steel.  I think it will be a pretty good match with the power the lathe has.


----------



## Qtron

Briney Eye said:


> Normal everyday use has not been a problem so far.  I'm taking pretty deep, fast cuts on aluminum with no issues.  The only time I've seen any anomalies is when I was cutting 8tpi Acme threads in 1144 Stressproof with a cheap Chinese carbide insert and it was digging in.  I actually stalled the spindle and slipped the belt a couple of times, which would be no different with change gears.  I took a couple more turns on the belt tension screw and then thought that it hung slightly a couple of times, but didn't stall long enough to error out the stepper drive (which takes a little less than a quarter turn on the motor shaft).  With the belt tightened, the lower ratio and a stouter motor I've got a good feeling about how it will perform, even in steel.  I think it will be a pretty good match with the power the lathe has.


Late night 4 U? Wasnt expecting a reply till late tonight. . Whats your local time?
Whats the HP of your lathe? Am quite surprised by ur last statement! Well done indeed. And all on the existing smaller 2 Nm nema 23 stepper?


----------



## Briney Eye

Qtron said:


> Late night 4 U? Wasnt expecting a reply till late tonight. . Whats your local time?
> Whats the HP of your lathe? Am quite surprised by ur last statement! Well done indeed. And all on the existing smaller 2 Nm nema 23 stepper?


Oh, it's 6:30pm here in New Mexico.  As for the match between the ELS and lathe, that's a fairly low bar since the lathe only has a 1/2hp motor.  That's still more than sufficient to break things in lower gears when there is no clutch, so having limited feed torque available is kind of a "feature."


----------



## Briney Eye

Qtron said:


> Late night 4 U? Wasnt expecting a reply till late tonight. . Whats your local time?
> Whats the HP of your lathe? Am quite surprised by ur last statement! Well done indeed. And all on the existing smaller 2 Nm nema 23 stepper?


It's after midnight there in Oz, isn't it?


----------



## RJSakowski

Briney Eye, did you find a source for the CL57T tuning software?  I tried using the Leadshine software but it only recognizes their products.


----------



## Qtron

Briney Eye said:


> It's after midnight there in Oz, isn't it?


No, its 12:45, arvo,


----------



## Qtron

Briney Eye said:


> Oh, it's 6:30pm here in New Mexico.  As for the match between the ELS and lathe, that's a fairly low bar since the lathe only has a 1/2hp motor.  That's still more than sufficient to break things in lower gears when there is no clutch, so having limited feed torque available is kind of a "feature."


Mines a 550lb 1 HP lathe, no VSD/VFD yet.
So I may end up needing a. ..Nm servo?
If ur needing a 3.4Nm then mine 6Nm servo?


----------



## Briney Eye

Qtron said:


> No, its 12:45, arvo,


Oops.  I went the wrong way 'round.


----------



## Briney Eye

RJSakowski said:


> Briney Eye, did you find a source for the CL57T tuning software?  I tried using the Leadshine software but it only recognizes their products.


It's been months, but I think it was a version of the Leadshine Protuner software for their CS-something(?) motors.  I remember trying more than one version before I found one that would talk to it.  It was klunky and hard to understand, but things might have gotten better since.


----------



## Briney Eye

Qtron said:


> Mines a 550lb 1 HP lathe, no VSD/VFD yet.
> So I may end up needing a. ..Nm servo?
> If ur needing a 3.4Nm then mine 6Nm servo?


I will try to provide some kind of answer to that question in the next few days.  Assuming that you would be driving through your gearbox, you would have some leeway by virtue of the ratio selection available there.  Work backward from the maximum pulse rate that the ELS could output and scale things from there.  You will always have a practical limit on how fast you can spin the leadscrew.  I detect when I can't keep up and show an error, or the driver itself shuts down.  I just tested it and with the lathe running at 210rpm (no load) I was able to get to 5 1/2 tpi before the driver itself crapped out.  It would be sooner with the half nuts engaged, but it would be trying to move the carriage about 40 inches per minute.  When that happens I have to turn it off for a minute to reset.  Must be a thermal protection circuit.  So far it's always come back.  So far.


----------



## Qtron

Briney Eye said:


> I will try to provide some kind of answer to that question in the next few days.  Assuming that you would be driving through your gearbox, you would have some leeway by virtue of the ratio selection available there.  Work backward from the maximum pulse rate that the ELS could output and scale things from there.  You will always have a practical limit on how fast you can spin the leadscrew.  I detect when I can't keep up and show an error, or the driver itself shuts down.  I just tested it and with the lathe running at 210rpm (no load) I was able to get to 5 1/2 tpi before the driver itself crapped out.  It would be sooner with the half nuts engaged, but it would be trying to move the carriage about 40 inches per minute.  When that happens I have to turn it off for a minute to reset.  Must be a thermal protection circuit.  So far it's always come back.  So far.


I hope to be able to use lathe as designed, ie, down to 4 tpi, with 1/2 nuts in, doing real work in CS1040, or 40 ton steel. Will drive as U r, thru the gearbox. I think I would smash gbox if I stalled the leadscrew too, (no safety clutch provided)
But as KB said earlier, lighter cuts probably.


----------



## Qtron

Qtron said:


> I hope to be able to use lathe as designed, ie, down to 4 tpi, with 1/2 nuts in, doing real work in CS1040, or 40 ton steel. Will drive as U r, thru the gearbox. I think I would smash gbox if I stalled the leadscrew too, (no safety clutch provided)
> But as KB said earlier, lighter cuts probably.


Smash with backgears in, 70 rpm spindle, with the 1 HP motor, geared down thru gbox


----------



## Briney Eye

Qtron said:


> I hope to be able to use lathe as designed, ie, down to 4 tpi, with 1/2 nuts in, doing real work in CS1040, or 40 ton steel. Will drive as U r, thru the gearbox. I think I would smash gbox if I stalled the leadscrew too, (no safety clutch provided)
> But as KB said earlier, lighter cuts probably.





Qtron said:


> Smash with backgears in, 70 rpm spindle, with the 1 HP motor, geared down thru gbox


You're worrying me. Are you saying you just broke something?


----------



## Qtron

Briney Eye said:


> You're worrying me. Are you saying you just broke something?


''..think I would smash gbox if I stalled the leadscrew too, (no safety clutch provided)''
- So a separate drive via a stepper/servo is a good safety mechanism!


----------



## Qtron

Qtron said:


> ''..think I would smash gbox if I stalled the leadscrew too, (no safety clutch provided)''
> - So a separate drive via a stepper/servo is a good safety mechanism!


I mean smash would be highly likely if the backgears were employed, a massive torque increase.


----------



## whitmore

Briney Eye said:


> I've changed my setup ... and have my drive module set to 400 microsteps per rev.


That's the French setting.   400 microsteps per rev is exactly one grad per microstep.
The world's Francophile population salutes you, mon ami!


----------



## Qtron

whitmore said:


> That's the French setting.   400 microsteps per rev is exactly one grad per microstep.
> The world's Francophile population salutes you, mon ami!


Pardon Monsieur, but, malheureursement, I don't mind admitting that 1 grad isnt on my android units converter..


----------



## Briney Eye

I'm afraid that my ELS efforts are going to be on hold for a while.  My father's health has taken a bad turn and the family is gathering.

Thank you all for your interest.  I've been trying to get the code into good enough shape to post to GitHub.  I'll get back to it as soon as circumstances permit.


----------



## whitmore

Qtron said:


> Pardon Monsieur, but, malheureursement, I don't mind admitting that 1 grad isnt on my android units converter..


So, it might be time to edit it in;   /usr/share/misc/units.lib
is the place and
grad              .0025 turn
under "/ dimensionless" heading, is the line to add.

If memory serves, French artillery and HP-34c calculators also support that unit.


----------



## Qtron

Briney Eye said:


> I'm afraid that my ELS efforts are going to be on hold for a while.  My father's health has taken a bad turn and the family is gathering.
> 
> Thank you all for your interest.  I've been trying to get the code into good enough shape to post to GitHub.  I'll get back to it as soon as circumstances permit.


Am so sorry to hear Jon, hard time for U, your family. I guess he is in late 80's age, very hard to fight illness. Will be praying, kindest regards,
Qtron.


----------



## RJSakowski

Today I was making torque and force measurements on my G0602 lathe.  To measure torque, I made a 3" pulley to fit on the lead screw input shaft. I wrapped several turns of some light cord, one end secured through a small hole in the pulley and the other end with a loop to attach a 20 lb. digital scale.  The scale reading times the 1.5" radius will be the applied torque in lb.-in. and will measure torque from 0 to 30 lb.-in. or 480 oz.-in..  On the other end, I anchored one side a 50 lb. digital scale to the tailstock  and the other side to the carriage.

I had previously decided to use the 2:1 gear reduction in the gear box.  My first measurement was of the torque required to turn the lead screw.  There was some stiction on startup and some variability in the readings but the dynamic torque ranged between 5 and 10 oz.-in. Next was with the half nuts engaged but no load. Here was a  bit of a surprise.  The required torque  was 91 oz.-in.  Considering that the stepper that I am using has a torque of around 300 oz.-in. at 350 rpm, that is a lot of overhead.  

After some investigation I discovered that the half nuts had a death grip on the lead screw with the additional friction causing the large torque requirement.  Clearly, what I needed to do was to limit the travel of the half nut cam.  I pulled the apron, prepared to put some sort of a shim in and discovered that there was an M6 threaded hole directly below the thread dial which exited at the face of the half nut cam when the half nuts were closed.  Two M6 sets screws, one for the adjustment and the second as a lock, and I have my adjustable stop.  With set screws in place, the amount of backlash increased by about 3 thou.  The measured torque with the half nuts engaged and no load was 38 oz.-in.. I

t was interesting to find the threaded hole as I can think of no other reason for it other than my use.  The set screw(s) are not on the BOM so it isn't a case of parts missed in manufacturing.

Next was to measure torque with a load.  I put the 50 lb. scale in place and engaged the lead screw.  At 50 lbs. of force working against the carriage travel, I measured 91 oz.-in. of torque.  Given that 38 oz.-on. is due to the frictional losses, that nets out at 53 oz.-in. or approximately an oz.-in. of torque for each lb. of resisting force.  Assuming that I really do have 300 pz.-in of available torque, I should net out at around 250 lbs. of available force at the carriage.


----------



## Qtron

whitmore said:


> So, it might be time to edit it in;   /usr/share/misc/units.lib
> is the place and
> grad              .0025 turn
> under "/ dimensionless" heading, is the line to add.
> 
> If memory serves, French artillery and HP-34c calculators also support that unit.


So 1 grad = 0.9 degrees of rotation?


----------



## Qtron

RJSakowski said:


> Today I was making torque and force measurements on my G0602 lathe.  To measure torque, I made a 3" pulley to fit on the lead screw input shaft. I wrapped several turns of some light cord, one end secured through a small hole in the pulley and the other end with a loop to attach a 20 lb. digital scale.  The scale reading times the 1.5" radius will be the applied torque in lb.-in. and will measure torque from 0 to 30 lb.-in. or 480 oz.-in..  On the other end, I anchored one side a 50 lb. digital scale to the tailstock  and the other side to the carriage.
> 
> I had previously decided to use the 2:1 gear reduction in the gear box.  My first measurement was of the torque required to turn the lead screw.  There was some stiction on startup and some variability in the readings but the dynamic torque ranged between 5 and 10 oz.-in. Next was with the half nuts engaged but no load. Here was a  bit of a surprise.  The required torque  was 91 oz.-in.  Considering that the stepper that I am using has a torque of around 300 oz.-in. at 350 rpm, that is a lot of overhead.
> 
> After some investigation I discovered that the half nuts had a death grip on the lead screw with the additional friction causing the large torque requirement.  Clearly, what I needed to do was to limit the travel of the half nut cam.  I pulled the apron, prepared to put some sort of a shim in and discovered that there was an M6 threaded hole directly below the thread dial which exited at the face of the half nut cam when the half nuts were closed.  Two M6 sets screws, one for the adjustment and the second as a lock, and I have my adjustable stop.  With set screws in place, the amount of backlash increased by about 3 thou.  The measured torque with the half nuts engaged and no load was 38 oz.-in.. I
> 
> t was interesting to find the threaded hole as I can think of no other reason for it other than my use.  The set screw(s) are not on the BOM so it isn't a case of parts missed in manufacturing.
> 
> Next was to measure torque with a load.  I put the 50 lb. scale in place and engaged the lead screw.  At 50 lbs. of force working against the carriage travel, I measured 91 oz.-in. of torque.  Given that 38 oz.-on. is due to the frictional losses, that nets out at 53 oz.-in. or approximately an oz.-in. of torque for each lb. of resisting force.  Assuming that I really do have 300 pz.-in of available torque, I should net out at around 250 lbs. of available force at the carriage.


I was reluctant to say that motor tuning may not provide the extra torque U were chasing.
But again a gulf of 450 - 500 lb may still exist,  ref Briney figures.
Thankyou RJ for this yardstick provided


----------



## Qtron

RJSakowski said:


> Today I was making torque and force measurements on my G0602 lathe.  To measure torque, I made a 3" pulley to fit on the lead screw input shaft. I wrapped several turns of some light cord, one end secured through a small hole in the pulley and the other end with a loop to attach a 20 lb. digital scale.  The scale reading times the 1.5" radius will be the applied torque in lb.-in. and will measure torque from 0 to 30 lb.-in. or 480 oz.-in..  On the other end, I anchored one side a 50 lb. digital scale to the tailstock  and the other side to the carriage.
> 
> I had previously decided to use the 2:1 gear reduction in the gear box.  My first measurement was of the torque required to turn the lead screw.  There was some stiction on startup and some variability in the readings but the dynamic torque ranged between 5 and 10 oz.-in. Next was with the half nuts engaged but no load. Here was a  bit of a surprise.  The required torque  was 91 oz.-in.  Considering that the stepper that I am using has a torque of around 300 oz.-in. at 350 rpm, that is a lot of overhead.
> 
> After some investigation I discovered that the half nuts had a death grip on the lead screw with the additional friction causing the large torque requirement.  Clearly, what I needed to do was to limit the travel of the half nut cam.  I pulled the apron, prepared to put some sort of a shim in and discovered that there was an M6 threaded hole directly below the thread dial which exited at the face of the half nut cam when the half nuts were closed.  Two M6 sets screws, one for the adjustment and the second as a lock, and I have my adjustable stop.  With set screws in place, the amount of backlash increased by about 3 thou.  The measured torque with the half nuts engaged and no load was 38 oz.-in.. I
> 
> t was interesting to find the threaded hole as I can think of no other reason for it other than my use.  The set screw(s) are not on the BOM so it isn't a case of parts missed in manufacturing.
> 
> Next was to measure torque with a load.  I put the 50 lb. scale in place and engaged the lead screw.  At 50 lbs. of force working against the carriage travel, I measured 91 oz.-in. of torque.  Given that 38 oz.-on. is due to the frictional losses, that nets out at 53 oz.-in. or approximately an oz.-in. of torque for each lb. of resisting force.  Assuming that I really do have 300 pz.-in of available torque, I should net out at around 250 lbs. of available force at the carriage.


Hope you can do a live test at 8 tpi in 20 or 40 ton steel, middle of the road depth of cuts..
I'd be interested in the carriage travel rate u set in that senario


----------



## RJSakowski

Qtron said:


> I was reluctant to say that motor tuning may not provide the extra torque U were chasing.
> But again a gulf of 450 - 500 lb may still exist,  ref Briney figures.
> Thankyou RJ for this yardstick provided


Yesterday, I tried unsuccessfully to use the Leadshine tuning software on my StepperOnline driver.  Unfortunately, the software only talks to Leadshine drivers.  My driver has an autotune feature but I wanted to see what was set for drive current and idle current. I sent an e-mail to StepperOnline asking where I can find their software.

My power supply is actually a 48 volt supply which was reset to 36 volts by the manufacturer.  I was able to boost the voltage to 42 volts with the voltage adjust pot.  Any further increase will no doubt involve changing a Zener reference diode or voltage divider.  42 volts will give me a 6 volt cushion for back EMF.  According to Leadshine a safe operating range for the power supply  is between 10% above minimum and 10% below maximum driver voltage which would be 43 volts.  Tomorrow, I'll have a go at trying the changes.


----------



## RJSakowski

For tomorrow's test, I won't reflash the firmware so I an 8 tpi thread will actually be 16 tpi at the lead screw and a.0040"/rev. feed will be .020" due to my 2:1 gear reduction.  The other area that I want to look at is low feed rates.  I had noticed some erratic movement before and I want to see if it has improved.  If everything looks good, I'll reflash the firmware.


----------



## Qtron

16 tpi sounds good.
Just finished documenting my auto feed rates avail on my lathe, a subject not related to threading, altho, using a stepper/servo via the gearbox enables normal lathe usage of the autofeed as well as threading. And therefore providing some crash safety too.
Autofeed rates on mine from slowest, with backgears, 60 rpm spindle, @ 0.2''/minute (0.0034''/Rev)
Thru to 3+ metres a minute (or 119.66''),
@ 1240 rpm.


----------



## Qtron

Qtron said:


> 16 tpi sounds good.
> Just finished documenting my auto feed rates avail on my lathe, a subject not related to threading, altho, using a stepper/servo via the gearbox enables normal lathe usage of the autofeed as well as threading. And therefore providing some crash safety too.
> Autofeed rates on mine from slowest, with backgears, 60 rpm spindle, @ 0.2''/minute (0.0034''/Rev)
> Thru to 3+ metres a minute (or 119.66''),
> @ 1240 rpm.


Autofeeds quoted are Z travel.


----------



## RJSakowski

OK  All hooked up and testing went well. No hitch in the gitalong at feed of .0005"/rev. @ 170 rpm or 580 rpm or at .063"/rev @ 580 rpm.  I cut a 3/8 16 thread (the coarsest possible with my current parameters) in hot rolled with .020" depth of cut on the first two passes without any issues.  Next, I turned some 1.5" steel, first at .063", 010" doc.  When I ran into the shoulder where the depth of cut would be about .05", the lathe stalled but the stepper didn't error out.

I reflashed the Launchpad to account for the 2:1 gearing that I added to the drive train. I redefined my lead screw pitch to 24 tpi rather than the actual 12 tpi to compensate for the gearing. A quick check shows that the setting is correct.

One question that I have is what is the action the controller takes when it receives an alarm signal?  The driver output goes high on a fault.


----------



## kb58

The answers will be in the code, but given that he hasn't said, I'd guess "nothing", or maybe the LED turns on. Probably just a stub in the code for now.


----------



## Qtron

RJSakowski said:


> OK  All hooked up and testing went well. No hitch in the gitalong at feed of .0005"/rev. @ 170 rpm or 580 rpm or at .063"/rev @ 580 rpm.  I cut a 3/8 16 thread (the coarsest possible with my current parameters) in hot rolled with .020" depth of cut on the first two passes without any issues.  Next, I turned some 1.5" steel, first at .063", 010" doc.  When I ran into the shoulder where the depth of cut would be about .05", the lathe stalled but the stepper didn't error out.
> 
> I reflashed the Launchpad to account for the 2:1 gearing that I added to the drive train. I redefined my lead screw pitch to 24 tpi rather than the actual 12 tpi to compensate for the gearing. A quick check shows that the setting is correct.
> 
> One question that I have is what is the action the controller takes when it receives an alarm signal?  The driver output goes high on a fault.


Maybe a Q for greatoldone! But sounds like you're on the road, makes me question the need for a servo. At 36 '' per minute carriage travel, thats not slow! 
Btw, What is the overall dia of ur leadscrew?


----------



## RJSakowski

Qtron said:


> Maybe a Q for greatoldone! But sounds like you're on the road, makes me question the need for a servo. At 36 '' per minute carriage travel, thats not slow!
> Btw, What is the overall dia of ur leadscrew?


My lead screw diameter is .792". I'm curious as to why you ask.

My lathe maxes out at 2400 rpm although I seldom operate above 750 rpm.   At 2400 rpm and .040"/rev, that's almost 100 ipm.  That would be around 2300 rpm from the stepper but it's crazy fast.  A more reasonable maximum for me would be 750 rpm and .020"/rev. for 15 ipm and 360 stepper rpm.  Even that is probably more than the spindle motor can handle.

With the closed loop hybrid stepper, the servo offers little advantage. It has a flatter torque curve but servos provide less torque for a given size.


----------



## Qtron

RJSakowski said:


> My lead screw diameter is .792". I'm curious as to why you ask.
> 
> My lathe maxes out at 2400 rpm although I seldom operate above 750 rpm.   At 2400 rpm and .040"/rev, that's almost 100 ipm.  That would be around 2300 rpm from the stepper but it's crazy fast.  A more reasonable maximum for me would be 750 rpm and .020"/rev. for 15 ipm and 360 stepper rpm.  Even that is probably more than the spindle motor can handle.
> 
> With the closed loop hybrid stepper, the servo offers little advantage. It has a flatter torque curve but servos provide less torque for a given size.


----------



## Qtron

RJSakowski said:


> My lead screw diameter is .792". I'm curious as to why you ask.
> 
> My lathe maxes out at 2400 rpm although I seldom operate above 750 rpm.   At 2400 rpm and .040"/rev, that's almost 100 ipm.  That would be around 2300 rpm from the stepper but it's crazy fast.  A more reasonable maximum for me would be 750 rpm and .020"/rev. for 15 ipm and 360 stepper rpm.  Even that is probably more than the spindle motor can handle.
> 
> With the closed loop hybrid stepper, the servo offers little advantage. It has a flatter torque curve but servos provide less torque for a given size.


Oh, OK, will fit an amt102 encoder to my dual shaft stepper then, cheers!
My leadscrew is 22 mm, or imperial equiv, so ½nut drag / friction overhead greater than yours.


----------



## Qtron

Qtron said:


> Oh, OK, will fit an amt102 encoder to my dual shaft stepper then, cheers!
> My leadscrew is 22 mm, or imperial equiv, so ½nut drag / friction overhead greater than yours.


well slightly, i mean!
its a 7/8" shaft but a bit of meat lost when made, so ended up at 22.16mm. 
i suppose the angle of attack of the tool for a given material would impact on carriage loading too.
rewatched part 4, Clough's alarm led on, he power cycles to reset. But dunno if he monitors it.


----------



## RJSakowski

Qtron said:


> well slightly, i mean!
> its a 7/8" shaft but a bit of meat lost when made, so ended up at 22.16mm.
> i suppose the angle of attack of the tool for a given material would impact on carriage loading too.
> rewatched part 4, Clough's alarm led on, he power cycles to reset. But dunno if he monitors it.


On my driver, when it lost steps,  the lost step led came on but as long as the motor's lost steps had not exceeded the preset(and unknown) threshold ,the feedback loop tries to compensate and the motor continues.  When the threshold is exceeded the driver shuts down and presumably sends the alarm to the controller.  The driver then has to be power cycled to resume.  The controller has no mechanism to shut the driver down having only PUL, DIR, and EN inputs.  I haven't tested the enable function but I suspect that it just inhibits the movement of the motor and doesn't shut the driver down.

Since the driver would most likely be buried in a control cabinet, it would be difficult to see the flashing LED.  Having an external signal for the user would be a plus.  I would guess that the alarm function would just be used to display the the error on the user control panel.  Since Clough has no individual LED for alarm, it would have to be displayed on the seven segment display; something like flashing all the decimal points in synchronization with the driver LED or trying to spell out the condition with the display limited alphanumeric capability.  The curiosity is that Clough recommended leaving the USE_ALARM_PIN enabled in his video #10.  I would think he would have disabled it until he had built in the functionality.

I haven't seen an over current or over voltage alarm yet so I don't know how the driver reacts.  According to the manual, the driver shuts down and has to be powered down to resume.  On lost steps, it flashes six times, not seven.  I counted the three times to be sure that I was counting right.  If the threshold is exceeded the driver shuts down.  This happened when I changed from forward to reverse at a fairly high leadscrew rpm.  Then I have to power down the driver to resume operation.  

I think the force presented to the carriage during turning will depend on a lot of factors besides material, depth of cut, and feed/rev.  Certainly a dull tool will require much greater force.  I am not sure of a good way to assess this  quantitatively.  A dynamometer on the lead screw or load cell directly driving the carriage.  As a rough estimate, the crank on my lathe is on a 3.5" circle so each revolution of the crank travels  3.5 x π" or 11".  18 full turns of the crank moves the carriage 17" so the mechanical advantage of the crank is 11 x 18/17 or 11.6.  Neglecting friction, one lb. of force applied to the crank will produce 11.6 lbs. of force at the carriage.


----------



## Qtron

RJSakowski said:


> On my driver, when it lost steps,  the lost step led came on but as long as the motor's lost steps had not exceeded the preset(and unknown) threshold ,the feedback loop tries to compensate and the motor continues.  When the threshold is exceeded the driver shuts down and presumably sends the alarm to the controller.  The driver then has to be power cycled to resume.  The controller has no mechanism to shut the driver down having only PUL, DIR, and EN inputs.  I haven't tested the enable function but I suspect that it just inhibits the movement of the motor and doesn't shut the driver down.
> 
> Since the driver would most likely be buried in a control cabinet, it would be difficult to see the flashing LED.  Having an external signal for the user would be a plus.  I would guess that the alarm function would just be used to display the the error on the user control panel.  Since Clough has no individual LED for alarm, it would have to be displayed on the seven segment display; something like flashing all the decimal points in synchronization with the driver LED or trying to spell out the condition with the display limited alphanumeric capability.  The curiosity is that Clough recommended leaving the USE_ALARM_PIN enabled in his video #10.  I would think he would have disabled it until he had built in the functionality.
> 
> I haven't seen an over current or over voltage alarm yet so I don't know how the driver reacts.  According to the manual, the driver shuts down and has to be powered down to resume.  On lost steps, it flashes six times, not seven.  I counted the three times to be sure that I was counting right.  If the threshold is exceeded the driver shuts down.  This happened when I changed from forward to reverse at a fairly high leadscrew rpm.  Then I have to power down the driver to resume operation.
> 
> I think the force presented to the carriage during turning will depend on a lot of factors besides material, depth of cut, and feed/rev.  Certainly a dull tool will require much greater force.  I am not sure of a good way to assess this  quantitatively.  A dynamometer on the lead screw or load cell directly driving the carriage.  As a rough estimate, the crank on my lathe is on a 3.5" circle so each revolution of the crank travels  3.5 x π" or 11".  18 full turns of the crank moves the carriage 17" so the mechanical advantage of the crank is 11 x 18/17 or 11.6.  Neglecting friction, one lb. of force applied to the crank will produce 11.6 lbs. of force at the carriage.


Yes agree with all stated re Alarm situ.
Maybe a word to Clough via his site may prompt a clarification re enabling the alarm status.
I am surprised clough's f/w allows a sudden reversal without a deceleration ramp, then stopping first!
Seeing that U already are set up, is there a need for rigorous measurements? Maybe just find a real world fail threshold, then address it.
Certain jobs I have avoided / wont do so wont need the HP to cut, one being course threading of stainless steel.
(Briney eye will probably gonna do a load cell/ strain gauge test on his carriage, later on.)
Rocketronics video of a vicious cut shows absurdly fast, deep low pitch cutting; you may have seen it. But its in aluminium AFAIK. 
Thankyou RJ, for the specifics re 6x flash, lost steps


----------



## RJSakowski

I had some question regarding the alarm and enable settings.  I left both as they were in the default settings (#define INVERT_ENABLE_PIN true and #define INVERT_ALARM_PIN true).

From the driver manual, I can leave the enable pins unconnected which from their circuit diagram would imply that enabled operation occurs with zero volts across the inputs.  Given that Clough has tied all three + pins and assuming that he used the same configuration as in #4 video, and the software settings use negative logic, I should measure 0 volts across the enable pins . I actually measured 3.48 volts.  It may be that Clough leaves the driver disabled except when he is sending step and direction.  I'll have to check that further. ( Maybe time to pull out the scope.)









I measured 3.29 volts across the alarm pins which is probably acceptable.  Just considering my 5.2 volt supply and the two 10K resistors in Clough's drawing, the voltage would be be 2.6 but adding in the LED voltage drop  in the optoisolator would bring the voltage near my measured voltage.  Allowable tolerances for the resistors could make up the difference.  However, from the software settings, 0 volts should be true which is the opposite of what I see.  I need to do some further investigating to clear this in my head.

I was hoping to use the enable signal to turn off the driver when I am not using the lead screw.  I will probably just cut the power to the driver instead.


----------



## Qtron

RJSakowski said:


> I had some question regarding the alarm and enable settings.  I left both as they were in the default settings (#define INVERT_ENABLE_PIN true and #define INVERT_ALARM_PIN true).
> 
> From the driver manual, I can leave the enable pins unconnected which from their circuit diagram would imply that enabled operation occurs with zero volts across the inputs.  Given that Clough has tied all three + pins and assuming that he used the same configuration as in #4 video, and the software settings use negative logic, I should measure 0 volts across the enable pins . I actually measured 3.48 volts.  It may be that Clough leaves the driver disabled except when he is sending step and direction.  I'll have to check that further. ( Maybe time to pull out the scope.)
> View attachment 307571
> View attachment 307572
> 
> 
> I measured 3.29 volts across the alarm pins which is probably acceptable.  Just considering my 5.2 volt supply and the two 10K resistors in Clough's drawing, the voltage would be be 2.6 but adding in the LED voltage drop  in the optoisolator would bring the voltage near my measured voltage.  Allowable tolerances for the resistors could make up the difference.  However, from the software settings, 0 volts should be true which is the opposite of what I see.  I need to do some further investigating to clear this in my head.
> 
> I was hoping to use the enable signal to turn off the driver when I am not using the lead screw.  I will probably just cut the power to the driver instead.


Am glad U are diving into all this, THANKYOU!! these details are not covered by Clough.
afaik, when enable pin is hi, in this setup, the H bridge is floating, so no stepper coil currents flow,, except, If the stepper is already in motion, & the drive is suddenly not enabled, (or disabled), the stepper back-emf will be dissipated by the bridge (intrinsic fet diodes or better, external fast diodes) & power supply rail protection diodes, as a recirculating current. Whether these diodes exist or not is unknown to me. But, they should be fitted if the manufacturer has scruples!
BTW, and this may not be pertinent to your drive type,
there is a warning i read somewhere re the low cost TB6560 ( https://www.ebay.com.au/itm/TB6560-...ngle-1Axis-Controller-Stepper-Motor-Drive-cw/) and this family of drives,
that the powering up & down sequence should be done in the correct order so as to not have the driver powered up without its inputs from the pc, or other signal source present first, vague memory here, sorry but cant clarify further. But U may know more..


----------



## RJSakowski

I'll have to try to deactivate the enable input to see if there really is no stepper current.  The manual says nothing about the enable signal other than it must be activated at least 5 µsec before the direction signal or step signal.  The controller is sending out a pulse stream whenever the lathe spindle is turning.  The simpler approach will be to power down the driver after stopping the spindle.  So far, that hasn't caused any problems shutting down either controller or driver first.


----------



## Qtron

RJSakowski said:


> I'll have to try to deactivate the enable input to see if there really is no stepper current.  The manual says nothing about the enable signal other than it must be activated at least 5 µsec before the direction signal or step signal.  The controller is sending out a pulse stream whenever the lathe spindle is turning.  The simpler approach will be to power down the driver after stopping the spindle.  So far, that hasn't caused any problems shutting down either controller or driver first.


I Been TRYING very hard, too hard- long Hrs, to prog the 'piccolo', I keep getting message,
Nothing to build, after selecting the 'hammer' tool
 Followed instructions precisely, except using latest release from github. Bah. Numb legs.
Maybe should go back to clough's first release.


----------



## RJSakowski

Qtron said:


> I Been TRYING very hard, too hard- long Hrs, to prog the 'piccolo', I keep getting message,
> Nothing to build, after selecting the 'hammer' tool
> Followed instructions precisely, except using latest release from github. Bah. Numb legs.
> Maybe should go back to clough's first release.


I am running the first release, 1.0.0 and had no problems in flashing the program.  I tried loading the 1.1.01 els-f280049c [active release] and the build completed and it got as far as preparing to flash.  It errored out because I didn't have the Launchpad connected but it looked like it would have flashed had it been connected.

I have had a bit of a diversion in assembling a properly built enclosure but I should have that completed tomorrow and will be back to some testing.


----------



## Qtron

RJSakowski said:


> I am running the first release, 1.0.0 and had no problems in flashing the program.  I tried loading the 1.1.01 els-f280049c [active release] and the build completed and it got as far as preparing to flash.  It errored out because I didn't have the Launchpad connected but it looked like it would have flashed had it been connected.
> 
> I have had a bit of a diversion in assembling a properly built enclosure but I should have that completed tomorrow and will be back to some testing.


Thanks RJ, will give the 1.1.01 els-f280049c a go then. I am not TI's  EDA compatible!!
Look FWD to ur testing then, cheers!


----------



## GreatOldOne

kb58 said:


> The answers will be in the code, but given that he hasn't said, I'd guess "nothing", or maybe the LED turns on. Probably just a stub in the code for now.





Qtron said:


> Maybe a Q for greatoldone! But sounds like you're on the road, makes me question the need for a servo. At 36 '' per minute carriage travel, thats not slow!
> Btw, What is the overall dia of ur leadscrew?



When I got my setup to alarm, the LED on the driver does indeed light - and the servo halts. A power cycle to the driver is required to get it to restart.


----------



## RJSakowski

GreatOldOne said:


> When I got my setup to alarm, the LED on the driver does indeed light - and the servo halts. A power cycle to the driver is required to get it to restart.


I get the same response from my driver.  No effect on the Launchpad controller.


----------



## Qtron

RJSakowski said:


> I get the same response from my driver.  No effect on the Launchpad controller.


Hiya RJ,
Got no further at this point, been distracted.
Am hoping that Briney eye's project will be completed when he is able to, of course, because, & I may be wrong, but I think he uses limit switches, which Clough42 does not do.
I reckon thats a must have feature.
A bit more messing about but a sliding position limit switch arrangement, set to be in line with the thread's gutter would be ideal.
Overspeed sensing is another important safety feature too, after seeing Mach3 / Smoothstepper go ape, and crash our router CNC at work.


----------



## RJSakowski

Qtron said:


> Hiya RJ,
> Got no further at this point, been distracted.
> Am hoping that Briney eye's project will be completed when he is able to, of course, because, & I may be wrong, but I think he uses limit switches, which Clough42 does not do.
> I reckon thats a must have feature.
> A bit more messing about but a sliding position limit switch arrangement, set to be in line with the thread's gutter would be ideal.
> Overspeed sensing is another important safety feature too, after seeing Mach3 / Smoothstepper go ape, and crash our router CNC at work.


I have a design on the back burner for an electromechanical limit switch using a solenoid activated trigger mechanism to pull the half nut lever.  The objective was to enable more precise end of travel for threading of machining to a shoulder.  If the enable circuit works out, it would be simpler to just disable the driver.  I have a mechanical stop on my ways which could be easily modified to operate an electrical circuit.  There are several issues that I see. 

The first is what type of proximity switching to use.  I would prefer to have position repeatability to within a thou and, in my experience, microswitches can't hold that. I added optoelectronic limit switching to my Tormach and it will hold +/- .0001" but care must be taken to avoid fouling of the optics.  Hall effect switches are another possibility but the magnet would have to be protected from picking up swarf.  I looked at my lathe and it appears that I might be able to mount the switch on the back side of the apron.

The second issue would be the addition of wires to the front of the lathe.  Any wiring adds to the clutter and creates the potential for tangling with turnings.  I think I would be able to route the wires through flexible SS conduit towards the tailstock.  I already have my DRO wiring routed in that direction and it hasn't been a hassle.

A third issue would be direction sensing.  Ideally, a stop moving forward would still permit moving in reverse and vice versa.  This could conceivably be done with steering circuitry, using the signal to the DIR input on the driver.


----------



## whitmore

RJSakowski said:


> I have a design on the back burner for an electromechanical limit switch using a solenoid activated trigger mechanism to pull the half nut lever.
> ... I would prefer to have position repeatability to within a thou and, in my experience, microswitches can't hold that. I added optoelectronic limit switching to my Tormach...


Optical switching  with good accuracy... can a DRO be programmed for that function?   Or, does this
really have to be a separate wired-in item?

There's good technology out there (LVDT comes to mind) for microinch triggered switches, if that is really necessary.   The half-nut
might not be as fast to disengage as an electric clutch, or motor brake solution.


----------



## RJSakowski

whitmore said:


> Optical switching  with good accuracy... can a DRO be programmed for that function?   Or, does this
> really have to be a separate wired-in item?
> 
> There's good technology out there (LVDT comes to mind) for microinch triggered switches, if that is really necessary.   The half-nut
> might not be as fast to disengage as an electric clutch, or motor brake solution.



My DRO's are not capable of outputing a signal at some preset position.

The advantage of optical switching is that I already have the design done.  The mechanical part would need to be modified but the circuit board is already done.  I don't believe that I would have to disengage the half nut.  I could simply cut the pulses to the driver. It might coast for a few steps but it should be fairly repeatable.  A full step is .00021" on my lathe.


----------



## Flyinfool

If you stop the lead screw at the gutter, how will you pick up the same lead for the next pass on the thread?


----------



## RJSakowski

Flyinfool said:


> If you stop the lead screw at the gutter, how will you pick up the same lead for the next pass on the thread?


Good point, thank yout!  The lead screw has to remain on in order to maintain the relationship with the spindle.  Back to disengaging the half nuts.


----------



## homebrewed

Based on some work I did in the long past, you may be able to further improve your optical switch'es resolution with a lens to focus the light to a smaller point at the interrupt point.  I was using a HeNe laser at that time so its diameter at the focal point was a few multiples of the wavelength -- 635nm.  White light won't be as good as that, but a decent diode laser module could get you pretty close.

As an aside, 635nm is 25 micro-inches.....


----------



## RJSakowski

homebrewed said:


> Based on some work I did in the long past, you may be able to further improve your optical switch'es resolution with a lens to focus the light to a smaller point at the interrupt point.  I was using a HeNe laser at that time so its diameter at the focal point was a few multiples of the wavelength -- 635nm.  White light won't be as good as that, but a decent diode laser module could get you pretty close.
> 
> As an aside, 635nm is 25 micro-inches.....


I installed optical homing on my Tormach 770 to improve homing repeatability some years ago.  I used an Omron OPB829DZ optointerupter, combined with regulated emitter LED current, comparison to a regulated reference voltage via an LM311 comparator, and well designed optics.  This provides consistent positioning to within +/- .0001", the resolution of my Tormach DRO.


----------



## Qtron

whitmore said:


> Optical switching  with good accuracy... can a DRO be programmed for that function?   Or, does this
> really have to be a separate wired-in item?
> 
> There's good technology out there (LVDT comes to mind) for microinch triggered switches, if that is really necessary.   The half-nut
> might not be as fast to disengage as an electric clutch, or motor brake solution.



The proximity sensor shown is on our router at work,
It is very low cost, its within 0.1 mm, BUT, has a repeatability of 0.01 mm !!
LVDT's have come a long way since first conceived, but wont match this on the same price/accuracy page.
I like the idea of a spindle motor brake, as synchronicity can be maintained with the LS.
One vid i saw (seen so many, hard to remember) has the operator cut a first pass, stop, reverse the lathe then, run fwd again &  cut the second pass etc, no 1/2 nut disengaged.
He did have a stepper on the cross-slide to slighly retract during 'rewind'.
Excellent system. It may have been Wade'O Design on youtube. No answers forthcoming on enquiries placed to his website, sadly.


----------



## RJSakowski

Tormach's Path Pilot controller has the ability, once homing has been set, to electronically stop the at the homing and far limit positions at the same position exactly with no overshoot, even when approaching at full rapid speed (130 ipm). To do so, it has to be decellerating as it approaches the limit position based upon feedback regarding its current position vs. target position.


----------



## Qtron

RJSakowski said:


> My DRO's are not capable of outputing a signal at some preset position.
> 
> The advantage of optical switching is that I already have the design done.  The mechanical part would need to be modified but the circuit board is already done.  I don't believe that I would have to disengage the half nut.  I could simply cut the pulses to the driver. It might coast for a few steps but it should be fairly repeatable.  A full step is .00021" on my lathe.


Whats a "Tormach's Path Pilot controller " whats its primary function? -web link?
Going back a few pages in this thread, Have you any idea why Briney Eye, Jon, was alarmed (.. Eek! ..) when he discovered Clough was doing sums on the fly in his code?- ( as vs Jon, & i guess many arduino users,  doing the math's first, then kicking off the stepper etc.)
is there a distinct advantange to Clough's approach? - a sudden spindle speed drop, or?


----------



## RJSakowski

Tormach makes several "personal" CNC machines.  Several years ago, they replaced the Mach 3 controller with a proprietary controller based on Linux CNC and called PathPilot. My 770 came with Mach 3 controller and if I ran full bore up to the limit switch, it would overshoot and hit a hard stop. 

With PathPilot, once you home the machine , you will not ever actually hit the limit switches (the home position is set about .050" shy of the limit switch).  PathPilot also programs in a far limit, the default position based on the machine parameters but user programmable so the machine works to electronic limit positions.

You can download the manual here: https://www.tormach.com/support/wpdmpro/um10349-pcnc1100-manual-0916a-web/  Some people running non Tormach machines are using PathPilot.  Since it is based on Linux CNC, it has to be open source. The communication is through a special board called a Mesa, IIRC.

I thought that Clough used a rather peculiar way of syncing the lead screw to the spindle.  He explains his logic in his second video, around 26 min. in.


----------



## Qtron

RJSakowski said:


> Tormach makes several "personal" CNC machines.  Several years ago, they replaced the Mach 3 controller with a proprietary controller based on Linux CNC and called PathPilot. My 770 came with Mach 3 controller and if I ran full bore up to the limit switch, it would overshoot and hit a hard stop.
> 
> With PathPilot, once you home the machine , you will not ever actually hit the limit switches (the home position is set about .050" shy of the limit switch).  PathPilot also programs in a far limit, the default position based on the machine parameters but user programmable so the machine works to electronic limit positions.
> 
> You can download the manual here: https://www.tormach.com/support/wpdmpro/um10349-pcnc1100-manual-0916a-web/  Some people running non Tormach machines are using PathPilot.  Since it is based on Linux CNC, it has to be open source. The communication is through a special board called a Mesa, IIRC.
> 
> I thought that Clough used a rather peculiar way of syncing the lead screw to the spindle.  He explains his logic in his second video, around 26 min. in.


Using mobile ph ATM, this forum's protocols wont allow upload of a ph file, but anyway I note from your kindly provided link to Tormach user manual, they use 3 phase steppers! Must be an advantage with them, or are they simply a lower cost device?
I presume the 770 is not cheap!
Maybe Mach 4 has solved the 'head butting' issues of Mach 3 as u defined, RJ.
Will replay vid 2 re Clough, THANKS!, but largely the Q re Jon's approach, vs Cloughs remains unclarified.
Certainly the arduino is cheaper,  easier to prog, (still no joy re mine not talking to the TI ide properly- I've asked Clough), and of course, the big appeal is Jon's touch screen, plus, and still the big unknown, the better torque achieved by fully utilizing the lathes gearbox (I don't mean change gears), an added complication of his ELS setup , but a worthwhile trade-off.


----------



## GreatOldOne

Flyinfool said:


> If you stop the lead screw at the gutter, how will you pick up the same lead for the next pass on the thread?



As per the video someone posted previously. Disengage the leadscrew when you hit the relief. Stop the lathe. Back the tool out, reverse the lathe and start it up. When the thread dial comes back to the mark you where using, re-engage the halfnuts. Run the lathe back to the beginning of the thread and stop the lathe. Push the tool back in, and put your cut on. Lathe back into forward, start. Rinse and repeat.

if you don’t have thread dial, you’ll need to keep the half nuts engaged, and try and stop the lathe in the relief - but the rest of the procedure stays the same.


----------



## Qtron

...


----------



## Qtron

RJSakowski said:


> Tormach makes several "personal" CNC machines.  Several years ago, they replaced the Mach 3 controller with a proprietary controller based on Linux CNC and called PathPilot. My 770 came with Mach 3 controller and if I ran full bore up to the limit switch, it would overshoot and hit a hard stop.
> 
> With PathPilot, once you home the machine , you will not ever actually hit the limit switches (the home position is set about .050" shy of the limit switch).  PathPilot also programs in a far limit, the default position based on the machine parameters but user programmable so the machine works to electronic limit positions.
> 
> You can download the manual here: https://www.tormach.com/support/wpdmpro/um10349-pcnc1100-manual-0916a-web/  Some people running non Tormach machines are using PathPilot.  Since it is based on Linux CNC, it has to be open source. The communication is through a special board called a Mesa, IIRC.
> 
> I thought that Clough used a rather peculiar way of syncing the lead screw to the spindle.  He explains his logic in his second video, around 26 min. in.


Wish u defined peculiar re syncing with the encoder!, re listened, makes sense, well, from a layman's p.o.v., but the floating point method is not necessarily more accurate than Jon's.. he said, 1 in 32000 of an inch. That was probably not your main point tho.


----------



## Qtron

GreatOldOne said:


> As per the video someone posted previously. Disengage the leadscrew when you hit the relief. Stop the lathe. Back the tool out, reverse the lathe and start it up. When the thread dial comes back to the mark you where using, re-engage the halfnuts. Run the lathe back to the beginning of the thread and stop the lathe. Push the tool back in, and put your cut on. Lathe back into forward, start. Rinse and repeat.
> 
> if you don’t have thread dial, you’ll need to keep the half nuts engaged, and try and stop the lathe in the relief - but the rest of the procedure stays the same.


Hiya Greatoldone,
Did u prog Clough's board on a 32 bit machine, or 64 bit? And did u do it via the JTAG, or via the USB debug probe? (USB port).


----------



## Qtron

GreatOldOne said:


> As per the video someone posted previously. Disengage the leadscrew when you hit the relief. Stop the lathe. Back the tool out, reverse the lathe and start it up. When the thread dial comes back to the mark you where using, re-engage the halfnuts. Run the lathe back to the beginning of the thread and stop the lathe. Push the tool back in, and put your cut on. Lathe back into forward, start. Rinse and repeat.
> 
> if you don’t have thread dial, you’ll need to keep the half nuts engaged, and try and stop the lathe in the relief - but the rest of the procedure stays the same.


Or u can simply, manually set the tool in the thread, by a good eye, wind back, set depth then restart lathe.. a pita tho, lol


----------



## RJSakowski

Qtron said:


> Using mobile ph ATM, this forum's protocols wont allow upload of a ph file, but anyway I note from your kindly provided link to Tormach user manual, they use 3 phase steppers! Must be an advantage with them, or are they simply a lower cost device?
> I presume the 770 is not cheap!
> Maybe Mach 4 has solved the 'head butting' issues of Mach 3 as u defined, RJ.
> Will replay vid 2 re Clough, THANKS!, but largely the Q re Jon's approach, vs Cloughs remains unclarified.
> Certainly the arduino is cheaper,  easier to prog, (still no joy re mine not talking to the TI ide properly- I've asked Clough), and of course, the big appeal is Jon's touch screen, plus, and still the big unknown, the better torque achieved by fully utilizing the lathes gearbox (I don't mean change gears), an added complication of his ELS setup , but a worthwhile trade-off.


I bought my 770 eight years ago, almost to the day.  We had just sold our startup company and it was a gift to myself.  I wanted the capability that a CNC mill has and made up a package to include maximum machining options at the time, including 4th axis and the TTS tooling system and the package set me back over $14K.  

As to why Tormach chose 3 phase steppers, I don't know.  They are NEMA 34 motors.  The rated torque for the x and y motors is 600 oz.-in. but the only time that I have lost steps has been on a hard crash.  It was the reason that I decided to go with the 602 oz.-in. stepper for the ELS.  They are driving 4mm pitch ball screws with angular contact thrust bearings so friction is reduced considerably (I believe that my total frictional load is around 50 oz.-in.) and they are driving with 80 volts vs. my 42 volts.  My suspicion is that 3 phase offers an advantage over the two phase motor, particularly when microstepping.  IIRC, microstepping is achieved by reducing the current to the windings by sine and cosine factors of the angle between the steps.

When I first read about Clough's strategy, I thought it a bit cumbersome to count steps from the point of the beginning and produce driver steps according to a given ratio of the encoder step count but I may have been over simplifying it.  I guess the issue is the spindle rpm isn't a constant and can change with applied load but I am a long way from being an authority on these matters.

As to why Tormach went with the Linux CNC engine rather than moving to Mach 4, I believe that there were several factors at play.  Mach 3 wasn't cutting it and they needed to move on.  Mach 4 was still in development and I guess they liked what they saw in PathPilot. I really haven't used it much but Path Pilot is definitely superior to Mach 3.  I am way behind on version updates and they have added a lot more features to the controller from the version that I am using.

Back to the ELS, I would like to see the ability to add user defined lead and thread pitch rather than the preset values.  It would be nice to be able to set up some custom thread pitch if desired. Another nicety would be changing feed and pitch by just holding the buttons down rather than separate presses.  However, the Clough controller offers greater thread capability than the geared option so I am still better off.


----------



## RJSakowski

Qtron said:


> Hiya Greatoldone,
> Did u prog Clough's board on a 32 bit machine, or 64 bit? And did u do it via the JTAG, or via the USB debug probe? (USB port).


The TI IDE only works on a 64 bit machine as I found out when I tried loading it on my laptop.


----------



## GreatOldOne

Qtron said:


> Hiya Greatoldone,
> Did u prog Clough's board on a 32 bit machine, or 64 bit? And did u do it via the JTAG, or via the USB debug probe? (USB port).



64 bit MacOS, via usb.


----------



## kb58

I'll preface this by saying that it may be my setup, but the Clough42 ELS hiccupped on me.

I had it set for a feed rate of 0.020" and had used it successfully several times. I put another part in and engaged the feed, then noticed that it was moving much faster. Somehow, it switched from Feed to Thread, and though I don't remember the actual thread number displayed, it wasn't as desired!

So, it "may" be EMI in my setup, so I'll keep an eye on it each time I start the lathe. If that's it, cables will be shielded and/or separated. It "may" also be the software, and as Clough42 said himself, this is beta code and not for anything important. So, yeah, as more people get these up and running, we need to keep an eye on things. And to be clear, I don't blame James for any of this, and very much appreciate him contributing such a cool tool to the community.


----------



## Qtron

RJSakowski said:


> I bought my 770 eight years ago, almost to the day.  We had just sold our startup company and it was a gift to myself.  I wanted the capability that a CNC mill has and made up a package to include maximum machining options at the time, including 4th axis and the TTS tooling system and the package set me back over $14K.
> 
> As to why Tormach chose 3 phase steppers, I don't know.  They are NEMA 34 motors.  The rated torque for the x and y motors is 600 oz.-in. but the only time that I have lost steps has been on a hard crash.  It was the reason that I decided to go with the 602 oz.-in. stepper for the ELS.  They are driving 4mm pitch ball screws with angular contact thrust bearings so friction is reduced considerably (I believe that my total frictional load is around 50 oz.-in.) and they are driving with 80 volts vs. my 42 volts.  My suspicion is that 3 phase offers an advantage over the two phase motor, particularly when microstepping.  IIRC, microstepping is achieved by reducing the current to the windings by sine and cosine factors of the angle between the steps.
> 
> When I first read about Clough's strategy, I thought it a bit cumbersome to count steps from the point of the beginning and produce driver steps according to a given ratio of the encoder step count but I may have been over simplifying it.  I guess the issue is the spindle rpm isn't a constant and can change with applied load but I am a long way from being an authority on these matters.
> 
> As to why Tormach went with the Linux CNC engine rather than moving to Mach 4, I believe that there were several factors at play.  Mach 3 wasn't cutting it and they needed to move on.  Mach 4 was still in development and I guess they liked what they saw in PathPilot. I really haven't used it much but Path Pilot is definitely superior to Mach 3.  I am way behind on version updates and they have added a lot more features to the controller from the version that I am using.
> 
> Back to the ELS, I would like to see the ability to add user defined lead and thread pitch rather than the preset values.  It would be nice to be able to set up some custom thread pitch if desired. Another nicety would be changing feed and pitch by just holding the buttons down rather than separate presses.  However, the Clough controller offers greater thread capability than the geared option so I am still better off.


Wow u must have a lot of customers for $14 k spend. Slick machine! 
BTW, after relisten to vid 2 I suddenly realised he has no accel/decel built in. Not good.


----------



## Qtron

kb58 said:


> I'll preface this by saying that it may be my setup, but the Clough42 ELS hiccupped on me.
> 
> I had it set for a feed rate of 0.020" and had used it successfully several times. I put another part in and engaged the feed, then noticed that it was moving much faster. Somehow, it switched from Feed to Thread, and though I don't remember the actual thread number displayed, it wasn't as desired!
> 
> So, it "may" be EMI in my setup, so I'll keep an eye on it each time I start the lathe. If that's it, cables will be shielded and/or separated. It "may" also be the software, and as Clough42 said himself, this is beta code and not for anything important. So, yeah, as more people get these up and running, we need to keep an eye on things. And to be clear, I don't blame James for any of this, and very much appreciate him contributing such a cool tool to the community.





kb58 said:


> I'll preface this by saying that it may be my setup, but the Clough42 ELS hiccupped on me.
> 
> I had it set for a feed rate of 0.020" and had used it successfully several times. I put another part in and engaged the feed, then noticed that it was moving much faster. Somehow, it switched from Feed to Thread, and though I don't remember the actual thread number displayed, it wasn't as desired!
> 
> So, it "may" be EMI in my setup, so I'll keep an eye on it each time I start the lathe. If that's it, cables will be shielded and/or separated. It "may" also be the software, and as Clough42 said himself, this is beta code and not for anything important. So, yeah, as more people get these up and running, we need to keep an eye on things. And to be clear, I don't blame James for any of this, and very much appreciate him contributing such a cool tool to the community.


Thanks for the heads up KB58


----------



## Qtron

GreatOldOne said:


> 64 bit MacOS, via usb.


Maybe TI 32 bit version, which I fully updated is my problem then


----------



## RJSakowski

No cus


Qtron said:


> Wow u must have a lot of customers for $14 k spend. Slick machine!
> BTW, after relisten to vid 2 I suddenly realised he has no accel/decel built in. Not good.


No customers.  Strictly hobby.  It was a self administered present for my immanent retirement.  Actually, I had a kitchen lighting project that could only be done with a CNC mill.  I could have farmed it out at a cost of several thousand $ but what fun is that?

As to the lack of accel/decel, I wouldn't be concerned about it.  The stepper is always tracking the spindle and the spindle's natural momentum will limit acceleration and deceleration.


----------



## Qtron

RJSakowski said:


> No cus
> 
> No customers.  Strictly hobby.  It was a self administered present for my immanent retirement.  Actually, I had a kitchen lighting project that could only be done with a CNC mill.  I could have farmed it out at a cost of several thousand $ but what fun is that?
> 
> As to the lack of accel/decel, I wouldn't be concerned about it.  The stepper is always tracking the spindle and the spindle's natural momentum will limit acceleration and deceleration.


Agree re fun too.
Good point re accel. I was thinking purely of the mass of my LS considering its length. But yes spindle dictates.
I suppose you will be watching for that potential flaw / setup sensitivity KB58 described.
BTW, u seem very studious! Thanks for info re 50 oz in friction of the 770, a good observation!


----------



## RJSakowski

I completed the ELS build this afternoon.  The last task was to make the faceplate for the display module.  I used a piece of .063" sheet aluminum for the panel.  I used my spindle mounted microscope in the Tormach CNC is an optical comparator to scan the display pcb  to determine the position of the components and laid out the panel in SolidWorks.  Since I had no way to make the flexible keypad, I opted for simple round buttons. For a bezel for the seven segment display, I used a piece of 1/8" red acrylic and I milled a shoulder  around the perimeter so the bezel would be flush with the front of the panel but still retained by the seven segment display.  This required .330" standoffs for the display pcb mount.  For the push button switches, I made Delrin top hat button extensions, 





I replaced the original LED's with new so I could take advantage of the longer leads to bring the LED's through the panel. The panel lettering was set up in SolidWorks.  In engraving fonts, it is desireable to use a single line font.  Unfortunately, Truetype fons are outline fonts. I chose the SWGDT font as the spacing is close enough that for all intents and purposes, it is a single line. For the switch lables, I used a 6 pt. font to avoid crowding  due to the close spacing of the switches.  For the LED's, the spacing was more  relaxed so I used a 9 pt. font there.  The G code was done in SprutCam.  Engraving was .008" deep, using a 30º engraving tool.  I chose .187" for the push button diameter so I could use my 3/16" 5C collet in the collet chuck.  

To make the seven buttons, I used 1/4" black Delrin rod with the first op done with the three jaw.  I 
used my carbide parting tool for all machining. To machine the button, I set up my carriage stop plus an 1/8" spacer.  With this setting, I faced the top of the button.  Then I pulled the spacer and cut the shoulder. Then I moved the carriage to slightly past the facing position and move the stock so that I could part a slightly over length part. The spacer was reinserted and the second part was made.  Once all the buttons were made, I switched to the 5C collet chuck with a 3/16" collet.  The part was inserted in the collet and the carriage set up to cut a .152" length.  When using a collet in this manner, especially on a material like Delrin, it is important to use consistent torque on the chuck key as the more torque you use, the deeper the collet is seated and the longer the part will be.  I tightened the key until I could just feel some resistance.

The lettering was filled in with Rustoleum flat black spray on a plastic sheet and applied with a swab.  The excess was sanded off with 360 grit wet and the faceplate was coated with automotive clear coat.

The enclosure is a phenolic box acquired many years ago.  It is mounted on a second box made from a piece of 3" aluminum channel and a cover plate.  This box houses the two power switches, one for the driver and the other for the controller, plus a fuse.  That box is mounted on a repurposed residential mains fuse box which contains the 42 volt power supply for the driver, a 5 volt power supply for the Clough42 board and Launchpad. and the stepper driver.




ELS Faceplate back





ELS Faceplate front





ELS Control and Power enclosures, mounted





ELS mechanical


----------



## RJSakowski

Qtron said:


> Agree re fun too.
> Good point re accel. I was thinking purely of the mass of my LS considering its length. But yes spindle dictates.
> I suppose you will be watching for that potential flaw / setup sensitivity KB58 described.
> BTW, u seem very studious! Thanks for info re 50 oz in friction of the 770, a good observation!


Thanks for the compliment.

I already found that the stepper doesn't like 5mm/rev @ 588 rpm.  It will handle 2.5mm/rev and possibly higher.  5mm/rev is 130 ipm at that spindle rpm.  However, so far no other issues.  Lots more testing to do.

The friction torque was measured as a better way to set preload on the angular contact thrust bearings.  Tormach's recommendation was to loosen the gib to remove any friction associated with it and then loosen the thrust bearing.  In theory, the remaining friction is due to the ball nut.  Then slowly increase the bearing preload as you rotate the ball screw, stopping as you start to feel some resistance.  That is where I devised the torque meter to measure the increase.  My initial torque was 21 oz.-in. and I tightened the preload to 37 oz. in.  Then I tightened the gib to the final 50 oz.-in.  I did a thread here. https://www.hobby-machinist.com/threads/measuring-ball-and-lead-screw-torque.37492/  John Saunders, NYC CNC, picked up on it and did a You Tube video on it as well.


----------



## kb58

Clough42 recommends against bundling the encoder and servo cables, for EMI reasons.  I bundled mine and had it hiccup (change settings) on me, so he may be right.


----------



## Qtron

kb58 said:


> Clough42 recommends against bundling the encoder and servo cables, for EMI reasons.  I bundled mine and had it hiccup (change settings) on me, so he may be right.


Encoder input on the piccolo would be impacted by EMR from the stepper/ servo but I fail to see how that would cause it to jump from feed to thread mode or vv.
But the MCU should be in a metal box with earthing strategy well thought thru.!


----------



## GreatOldOne

> I fail to see how that would cause it to jump from feed to thread mode or vv.



At a guess, it’s probably down to the coms to and from the keypad to the launchpad. It’s serialish IIRC... noise on the data line could be misinterpreted by the launchpad, and it does the switching thinking it’s a legitimate command from the pad - sending the change of state back to the pad.


----------



## Qtron

GreatOldOne said:


> At a guess, it’s probably down to the coms to and from the keypad to the launchpad. It’s serialish IIRC... noise on the data line could be misinterpreted by the launchpad, and it does the switching thinking it’s a legitimate command from the pad - sending the change of state back to the pad.


Ur right, of course, was regretting that statement overnight, lol.
I guess its best to have short leads from piccolo to the ''led&key''. (Maybe place both in the same metaI box?).
I  read somewhere that in some situations a ferrite bead on the earth wire/lead to a sensitive device on the end of a chain provides better noise immunity..
But maybe not relevant if cables/wires are short.
I do think a ferrite bead on the encoder cable right at the piccolo would be beneficial.
(Think of better type of USB Leads for PC's etc.)


----------



## Qtron

RJSakowski said:


> Thanks for the compliment.
> 
> I already found that the stepper doesn't like 5mm/rev @ 588 rpm.  It will handle 2.5mm/rev and possibly higher.  5mm/rev is 130 ipm at that spindle rpm.  However, so far no other issues.  Lots more testing to do.
> 
> The friction torque was measured as a better way to set preload on the angular contact thrust bearings.  Tormach's recommendation was to loosen the gib to remove any friction associated with it and then loosen the thrust bearing.  In theory, the remaining friction is due to the ball nut.  Then slowly increase the bearing preload as you rotate the ball screw, stopping as you start to feel some resistance.  That is where I devised the torque meter to measure the increase.  My initial torque was 21 oz.-in. and I tightened the preload to 37 oz. in.  Then I tightened the gib to the final 50 oz.-in.  I did a thread here. https://www.hobby-machinist.com/threads/measuring-ball-and-lead-screw-torque.37492/  John Saunders, NYC CNC, picked up on it and did a You Tube video on it as well.


Will check out vid. Very good, lots of fiddle for  U.
Try the damper plate technique on your stepper.
May raise the revs. Whats ur microstepping rate set to? (U may have already stated).


----------



## Qtron

RJSakowski said:


> I completed the ELS build this afternoon.  The last task was to make the faceplate for the display module.  I used a piece of .063" sheet aluminum for the panel.  I used my spindle mounted microscope in the Tormach CNC is an optical comparator to scan the display pcb  to determine the position of the components and laid out the panel in SolidWorks.  Since I had no way to make the flexible keypad, I opted for simple round buttons. For a bezel for the seven segment display, I used a piece of 1/8" red acrylic and I milled a shoulder  around the perimeter so the bezel would be flush with the front of the panel but still retained by the seven segment display.  This required .330" standoffs for the display pcb mount.  For the push button switches, I made Delrin top hat button extensions,
> View attachment 308143
> 
> I replaced the original LED's with new so I could take advantage of the longer leads to bring the LED's through the panel. The panel lettering was set up in SolidWorks.  In engraving fonts, it is desireable to use a single line font.  Unfortunately, Truetype fons are outline fonts. I chose the SWGDT font as the spacing is close enough that for all intents and purposes, it is a single line. For the switch lables, I used a 6 pt. font to avoid crowding  due to the close spacing of the switches.  For the LED's, the spacing was more  relaxed so I used a 9 pt. font there.  The G code was done in SprutCam.  Engraving was .008" deep, using a 30º engraving tool.  I chose .187" for the push button diameter so I could use my 3/16" 5C collet in the collet chuck.
> 
> To make the seven buttons, I used 1/4" black Delrin rod with the first op done with the three jaw.  I
> used my carbide parting tool for all machining. To machine the button, I set up my carriage stop plus an 1/8" spacer.  With this setting, I faced the top of the button.  Then I pulled the spacer and cut the shoulder. Then I moved the carriage to slightly past the facing position and move the stock so that I could part a slightly over length part. The spacer was reinserted and the second part was made.  Once all the buttons were made, I switched to the 5C collet chuck with a 3/16" collet.  The part was inserted in the collet and the carriage set up to cut a .152" length.  When using a collet in this manner, especially on a material like Delrin, it is important to use consistent torque on the chuck key as the more torque you use, the deeper the collet is seated and the longer the part will be.  I tightened the key until I could just feel some resistance.
> 
> The lettering was filled in with Rustoleum flat black spray on a plastic sheet and applied with a swab.  The excess was sanded off with 360 grit wet and the faceplate was coated with automotive clear coat.
> 
> The enclosure is a phenolic box acquired many years ago.  It is mounted on a second box made from a piece of 3" aluminum channel and a cover plate.  This box houses the two power switches, one for the driver and the other for the controller, plus a fuse.  That box is mounted on a repurposed residential mains fuse box which contains the 42 volt power supply for the driver, a 5 volt power supply for the Clough42 board and Launchpad. and the stepper driver.
> View attachment 308149
> 
> ELS Faceplate back
> 
> View attachment 308150
> 
> ELS Faceplate front
> 
> View attachment 308148
> 
> ELS Control and Power enclosures, mounted
> 
> View attachment 308151
> 
> ELS mechanical


Very nice RJ.
Any chance of dxf files for the front panel?


----------



## RJSakowski

Qtron said:


> Very nice RJ.
> Any chance of dxf files for the front panel?


This should be it.


----------



## RJSakowski

Qtron said:


> Will check out vid. Very good, lots of fiddle for  U.
> Try the damper plate technique on your stepper.
> May raise the revs. Whats ur microstepping rate set to? (U may have already stated).


My driver is set for 8 microsteps.

I am unfamiliar with the term "damper plate technique"


----------



## Qtron

RJSakowski said:


> My driver is set for 8 microsteps.
> 
> I am unfamiliar with the term "damper plate technique"


Sorry posted earlier in this thread.
A search on steppers should reveal. A co., in think in France makes them.
Its a simple disc of steel, scaled according to stepper size, fitted onto the shaft w grub screw, to help dampen mechanical resonance.
But at 8 micros u simply may be running it up to its limits,  depending on its inductance, etc.
If its a mech resonance issue, u can usually hear it growling, or not sounding  smooth.


----------



## Qtron

RJSakowski said:


> This should be it.


Cheers!


----------



## Qtron

Qtron said:


> Will check out vid. Very good, lots of fiddle for  U.
> Try the damper plate technique on your stepper.
> May raise the revs. Whats ur microstepping rate set to? (U may have already stated).


Cant find his ballscrew measuring vid... huge no. Of Vids!


----------



## Qtron

RJSakowski said:


> My driver is set for 8 microsteps.
> 
> I am unfamiliar with the term "damper plate technique"


ah goofed, Not French! but Oriental Motors make dampers and a bit more than just a lump of steel..


----------



## RJSakowski

Qtron said:


> ah goofed, Not French! but Oriental Motors make dampers


 edit: somehow, I missed your attachments.  Disregard the following two sentences. I couldn't find anything on dampers on the Oriental Motors website. An online search just yielded articles in dampers for motor mounts.  I haven't noticed any resonance issues but then I have limited options for the stepper rpm and I have yet to explore all possible settings.

Here is an article on stepper motors that some may find interesting.  One thing that I may try is adding a large capacitor to the driver p.s. input.  Most switching supplies have limited capacitive filtering, relying on feedback to keep the output voltage constant and it may be that the motor instantaneous current demand exceeds the p.s. capability.


----------



## homebrewed

There are other reasons you might want to add bypass capacitors to the power supply lines at the driver end of the connections.  Inductance of the connector wires, if they're long (or form a loop with substantial area between the line and ground return), could produce transients.  

I once was designing an audio amplifier, and this particular design produced some really nasty transients on its output when driven with a fast square wave.  I tried all kinds of things in the circuit, to no avail -- until I put an oscilloscope right on the output transistors' collectors (the power supply inputs).  Lo and behold, a really nasty transient!  Bypass caps right next to the output transistors cured the problem.  It didn't matter how beefy the PS wires were -- that has a small impact on the inductance.


----------



## RJSakowski

I did a couple of cuts using the ELS.  I successfully turned a length of 1" HR with a feed of .030"/rev. and .030" d.o.c. @ 588 rpm.  If I did the math right, that amounted to 1.66 cu. in./min which is a fairly healthy stock removal rate.  This amounts to a feed of almost 18 ipm and a stepper speed of 423 rpm.  (I use a 2:1 gear box reduction) so my stepper rpm is twice my lead screw rpm.)

When I tried .030"/rev. and .050 d.o.c., it stalled the lathe and chipped the insert in the process.

Looking a no load ceiling, at 3 mm/rev, the stepper tracks but it fails at 3.5mm/rev.  This corresponds to stepper speeds of 1667 and 1945 rpm, and 69 and 81 ipm, respectively.  

With that, I am fairly convinced that the ELS will be able to handle my needs.


----------



## Qtron

RJSakowski said:


> edit: somehow, I missed your attachments.  Disregard the following two sentences. I couldn't find anything on dampers on the Oriental Motors website. An online search just yielded articles in dampers for motor mounts.  I haven't noticed any resonance issues but then I have limited options for the stepper rpm and I have yet to explore all possible settings.
> 
> Here is an article on stepper motors that some may find interesting.  One thing that I may try is adding a large capacitor to the driver p.s. input.  Most switching supplies have limited capacitive filtering, relying on feedback to keep the output voltage constant and it may be that the motor instantaneous current demand exceeds the p.s. capability.


The mechanical Dampers may not be made any more as driver tuning mitigates the mech resonance issue somewhat.
Servo's easier to drive, & good drivers now have great PID tuning!
Thanks for the PDF, yes, unregulated linear supplies are actually a better choice than smps.
Reason is  they are 'softer'.. I mean they have nice big filter cap, pref. Low ESR, but also they are able to 'flex' a bit with the load. Smps cant, they're tightly reg'd. In the old days the unreg'd supply had a ballast resistor in series with the common lead of unipolar steppers. That R provided 2 features, load 'softening' to stop coil burnout, thus allowing a higher headroom voltage, (to overcome motor coil inductance), and also dampened coil resonances a bit.
You are probably aware of all this, but stated for those that may be interested.
Yes important to have that reservoir cap at the driver input, lowest ESR Panasonics!


----------



## Qtron

RJSakowski said:


> I did a couple of cuts using the ELS.  I successfully turned a length of 1" HR with a feed of .030"/rev. and .030" d.o.c. @ 588 rpm.  If I did the math right, that amounted to 1.66 cu. in./min which is a fairly healthy stock removal rate.  This amounts to a feed of almost 18 ipm and a stepper speed of 423 rpm.  (I use a 2:1 gear box reduction) so my stepper rpm is twice my lead screw rpm.)
> 
> When I tried .030"/rev. and .050 d.o.c., it stalled the lathe and chipped the insert in the process.
> 
> Looking a no load ceiling, at 3 mm/rev, the stepper tracks but it fails at 3.5mm/rev.  This corresponds to stepper speeds of 1667 and 1945 rpm, and 69 and 81 ipm, respectively.
> 
> With that, I am fairly convinced that the ELS will be able to handle my needs.


Great! Glad solution exists. Yeah 1900 rpm in bigger steppers is poking along a bit quick!
Max I achieved w mine, was about 1500 on the bench, so all good.


RJSakowski said:


> I did a couple of cuts using the ELS.  I successfully turned a length of 1" HR with a feed of .030"/rev. and .030" d.o.c. @ 588 rpm.  If I did the math right, that amounted to 1.66 cu. in./min which is a fairly healthy stock removal rate.  This amounts to a feed of almost 18 ipm and a stepper speed of 423 rpm.  (I use a 2:1 gear box reduction) so my stepper rpm is twice my lead screw rpm.)
> 
> When I tried .030"/rev. and .050 d.o.c., it stalled the lathe and chipped the insert in the process.
> 
> Looking a no load ceiling, at 3 mm/rev, the stepper tracks but it fails at 3.5mm/rev.  This corresponds to stepper speeds of 1667 and 1945 rpm, and 69 and 81 ipm, respectively.
> 
> With that, I am fairly convinced that the ELS will be able to handle my needs.


Am sure 1.66 ci would suit me too RJ, well done. 50 thou doc on smaller lathes is pretty vicious. Mine's a bit bigger, heavier, and wouldn't try that.
Looks like your tests show that your LS not being overloaded with reasonable cuts.
What was the Nm rating of your stepper again?
(Being lazy here).
So what happened re finding the right driver tuning software ( u had asked Briney eye).?


----------



## RJSakowski

Qtron said:


> Great! Glad solution exists. Yeah 1900 rpm in bigger steppers is poking along a bit quick!
> Max I achieved w mine, was about 1500 on the bench, so all good.
> 
> Am sure 1.66 ci would suit me too RJ, well done. 50 thou doc on smaller lathes is pretty vicious. Mine's a bit bigger, heavier, and wouldn't try that.
> Looks like your tests show that your LS not being overloaded with reasonable cuts.
> What was the Nm rating of your stepper again?
> (Being lazy here).
> So what happened re finding the right driver tuning software ( u had asked Briney eye).?


Yes, that is a far more aggressive cut than I would normally make.

The holding torque of my stepper is 4.25 Nm.   Remember that I am running a 2:1 gear reduction to the lead screw.  Looking at the torque curve, my findings fairly well corresponds to what the curve predicts.

I have not received a reply from StepperOnline about the tuning software as yet.  I sent a second request today.


----------



## Qtron

RJSakowski said:


> Yes, that is a far more aggressive cut than I would normally make.
> 
> The holding torque of my stepper is 4.25 Nm.   Remember that I am running a 2:1 gear reduction to the lead screw.  Looking at the torque curve, my findings fairly well corresponds to what the curve predicts.
> 
> I have not received a reply from StepperOnline about the tuning software as yet.  I sent a second request today.


Thanks, um, whats the breakaway torque?
Bit poor of stepperonline, but i Suspect leadshine are holding out.


----------



## RJSakowski

The pull out torque is about 3.3 Nm @ 30 rpm, 23.0@ 150 rpm, 2.5 @ 300 rpm, 1.75@ 450 rpm, and 1.30@ 600 rpm (from their graph).


----------



## Qtron

RJSakowski said:


> The pull out torque is about 3.3 Nm @ 30 rpm, 23.0@ 150 rpm, 2.5 @ 300 rpm, 1.75@ 450 rpm, and 1.30@ 600 rpm (from their graph).


Much appreciated RJ, i better let u make something


----------



## RJSakowski

Qtron said:


> Much appreciated RJ, i better let u make something


Mostly catching some shuteye.  There's a 17 hour time difference.


----------



## Qtron

RJSakowski said:


> Mostly catching some shuteye.  There's a 17 hour time difference.


Wish I could. 2:40 AM, unknown quantities walking up & down our street, loud voices, continual jabbering eminating from a house up the road. Nervous after theft from car in carport a few weeks ago. Cops said that night was very 'hot' in our street. They oft way too slow to respond. Manpower shortage.bah.


----------



## RJSakowski

The joys of urban life!  Our nearest neighbor is a quarter of a mile away and all our neighbors go to bed earlier than we do.  We also have very litle traffic on our road, especially  after 6PM.  It makes for a quiet life.


----------



## Qtron

RJSakowski said:


> The joys of urban life!  Our nearest neighbor is a quarter of a mile away and all our neighbors go to bed earlier than we do.  We also have very litle traffic on our road, especially  after 6PM.  It makes for a quiet life.


Time to move. . Getting too old for this crap. Jealous!
Anyway nice chatting RJ. Bon Nuit.


----------



## Qtron

RJSakowski said:


> The joys of urban life!  Our nearest neighbor is a quarter of a mile away and all our neighbors go to bed earlier than we do.  We also have very litle traffic on our road, especially  after 6PM.  It makes for a quiet life.


----------



## Qtron

Happy Christmas to you RJ, & all the Sakowski clan/s
Cheers, & lots of quiet nights too


----------



## Qtron

RJSakowski said:


> The joys of urban life!  Our nearest neighbor is a quarter of a mile away and all our neighbors go to bed earlier than we do.  We also have very litle traffic on our road, especially  after 6PM.  It makes for a quiet life.



Happy Christmas to you RJ, & all the Sakowski clan/s
Cheers, & lots of quiet nights too


----------



## RJSakowski

Qtron said:


> Happy Christmas to you RJ, & all the Sakowski clan/s
> Cheers, & lots of quiet nights too


And a very Merry Christmas to you and yours as well.

BTW, I had the tuning software all along.  I had downloaded the compressed file before I actually got the driver and hadn't bothered to install it.  My issue now is that I can't establish the COM link.  I wired up my own cable and as I recall, the RXD and TXD lines are crossed, but no joy.  I checked my COM port on my laptop with a loopback connection and it is functioning.  There's no way of checking the driver end though.  

Maybe it's a sign.  The first rule of engineering is if its working, don't fix it.


----------



## Qtron

RJSakowski said:


> And a very Merry Christmas to you and yours as well.
> 
> BTW, I had the tuning software all along.  I had downloaded the compressed file before I actually got the driver and hadn't bothered to install it.  My issue now is that I can't establish the COM link.  I wired up my own cable and as I recall, the RXD and TXD lines are crossed, but no joy.  I checked my COM port on my laptop with a loopback connection and it is functioning.  There's no way of checking the driver end though.
> 
> Maybe it's a sign.  The first rule of engineering is if its working, don't fix it.


Sorry missed the email prompt.
Thankyou for your sentiments too.
Yes agree re the E.rule
But am really curious, esp now u have done real world tests, as to what the tuning differences would actually be, if any.
Someone (Briney?) indicated that the software generally is clunky. So maybe a mysterious stepper driver setting needed? Or something in the s/w? Maybe another forum like cnczone can help.
I doubt if u are Robinson Crusoe here


----------



## RJSakowski

I guess my main interest was to see what the default operating parameters were.  I think the operation is close to the ragged edge but still functional.  My preference would be to have a greater operating margin.

I'm not sure why I can't connect.  The computer COM port is working; I verified that with another serial device.  As I read the CL57T diagram, TXD is an output and should be connected to the computer RXD pin and the RXD is an input and connected to the computer TXD pin.  Gnd is connected to Gnd pin on the computer and the +5 pin is unconnected.  It's possible that the CL57T driver serial connection is not functioning or the RJ11 plug isn't connecting, I suppose.


----------



## jaek

Is the board logic-level or RS-232? If it’s logic level you might need a transceiver to talk to the computer...

Baud rates and parity and such all match up?


----------



## RJSakowski

I finally got the driver to communicate with a computer, an old desktop running XT.  For some reason, it won't communicate with my laptop with identical COM port settings.

 Anyway, the settings of interest are: encoder resolution, 4000;  lock shaft current 40% of max; max following error 4000 counts; motor peak current, 8 amps.; and closed loop holding current, 45%.


----------



## Qtron

RJSakowski said:


> I finally got the driver to communicate with a computer, an old desktop running XT.  For some reason, it won't communicate with my laptop with identical COM port settings.
> 
> Anyway, the settings of interest are: encoder resolution, 4000;  lock shaft current 40% of max; max following error 4000 counts; motor peak current, 8 amps.; and closed loop holding current, 45%.


Great stuff RJ, what was on laptop, win 7?
Been trying to find this,
an interesting link re certain type of lower count encoder, cheeeep, but issues:








						Pauper's Rotary Encoder - Codrey Electronics
					

Quadrature Encoder is a familiar everyday sensor in robotics world. A quadrature encoder is a handy rotary encoder that let you know the speed and direction of a rotating shaft or linear motion. Let’s start […]




					www.codrey.com


----------



## RJSakowski

Qtron said:


> Great stuff RJ, what was on laptop, win 7?
> Been trying to find this,
> an interesting link re certain type of lower count encoder, cheeeep, but issues:
> 
> 
> 
> 
> 
> 
> 
> 
> Pauper's Rotary Encoder - Codrey Electronics
> 
> 
> Quadrature Encoder is a familiar everyday sensor in robotics world. A quadrature encoder is a handy rotary encoder that let you know the speed and direction of a rotating shaft or linear motion. Let’s start […]
> 
> 
> 
> 
> www.codrey.com


The laptop is running Win 7 Ultimate and the COM port is on the docking station.  I thought that I had solved the mystery when I discovered an internal connection between the RI pin and the DTR in the RS232 plug which I removed with a .045" drill but it is still not working.  I tried using a USB to RS 232 adapter but the lowest available COM port was 15 and the software only allows up to COM 10. .

I have another small desktop with an RS232 port which I will try.  I would like to have the ability to make changes in situ if necessary.

Thanks for the link on the encoder.  An interesting read.


----------



## Qtron

RJSakowski said:


> The laptop is running Win 7 Ultimate and the COM port is on the docking station.  I thought that I had solved the mystery when I discovered an internal connection between the RI pin and the DTR in the RS232 plug which I removed with a .045" drill but it is still not working.  I tried using a USB to RS 232 adapter but the lowest available COM port was 15 and the software only allows up to COM 10. .
> 
> I have another small desktop with an RS232 port which I will try.  I would like to have the ability to make changes in situ if necessary.
> 
> Thanks for the link on the encoder.  An interesting read.


I had been warned a while back re those rs232 adapters, compatibility. Thanks for that info re port limits.
Yes would be great if someone were to crack open the 4096 transitions encoder & see what booboos if any r inside!
BTW , never heard of win 7 Ultimate! Wonder if thats a north America special?


----------



## RJSakowski

Win 7 Ultimate is a combination of Win 7 home edition and the professional edition.  It include all of the media stuff.


----------



## RJSakowski

OK.  I dragged the desktop down to the shop and loaded the tuning software.  It works.  

A thought that I had is that the tuning software isn't compatible with Win 7 64 bit.  Both computers that run the software successfully are running 32 bit operating systems; one on XP and the other Win 7.


----------



## Qtron

RJSakowski said:


> OK.  I dragged the desktop down to the shop and loaded the tuning software.  It works.
> 
> A thought that I had is that the tuning software isn't compatible with Win 7 64 bit.  Both computers that run the software successfully are running 32 bit operating systems; one on XP and the other Win 7.


AM SOOO glad U said this, cos was contemplating a new 64 bit system after finding out the hard way that its impossible to program the piccolo using ver 8, 32 bit of the IDE. 
Clough's f/w was written in the 64 bit environs. I used another pc to do the programming & will use this 17" laptop for the tuning.


----------



## Qtron

RJSakowski said:


> OK.  I dragged the desktop down to the shop and loaded the tuning software.  It works.
> 
> A thought that I had is that the tuning software isn't compatible with Win 7 64 bit.  Both computers that run the software successfully are running 32 bit operating systems; one on XP and the other Win 7.


we seem to have missed the elephant in the room! or i did anyway
Re Briney eye & Leadscrew loading, 700 lb+ carriage forces etc, you obviously succeeded with the 25th D.O.C.'s for the 8 TPI or whatever,
So does this mean a loading capability of 700lb+ not required or?


----------



## RJSakowski

Qtron said:


> AM SOOO glad U said this, cos was contemplating a new 64 bit system after finding out the hard way that its impossible to program the piccolo using ver 8, 32 bit of the IDE.
> Clough's f/w was written in the 64 bit environs. I used another pc to do the programming & will use this 17" laptop for the tuning.


Thinking about it, the laptop is running Win 7 32 bit as welll so I am at a loss as to why  I can't connect with the laptop.


----------



## Qtron

RJSakowski said:


> Thinking about it, the laptop is running Win 7 32 bit as welll so I am at a loss as to why  I can't connect with the laptop.


Laptops are an issue for lots of reasons, will be a hardware compromise somewhere.
As an example, My longstanding friend, just tonight, reminded me not to use a laptop for fast applications.


----------



## RJSakowski

It doesn't take a lot of force on the carriage crank to stall out the stepper.  I calculated that I have a mechanical advantage of 11:1 with my hand crank so a few simple measurements should indicate the maximum force that the stepper can deliver to the carriage.   Back in post #132, I made some measurements of stall force that were fairly anemic but since then, I changed the gear ratio and increased the driver voltage.  I did some rough measurements this morning and it would be safe to say that I don't have much more than 100 lbs of force available.  

I really need some way of applying a direct force to the carriage.  Possibly a line over a pulley at the tailstock end lifting a dead weight?I have a pulley mounted for the flexible conduit from my cross slide DRO already.


----------



## Qtron

RJSakowski said:


> It doesn't take a lot of force on the carriage crank to stall out the stepper.  I calculated that I have a mechanical advantage of 11:1 with my hand crank so a few simple measurements should indicate the maximum force that the stepper can deliver to the carriage.   Back in post #132, I made some measurements of stall force that were fairly anemic but since then, I changed the gear ratio and increased the driver voltage.  I did some rough measurements this morning and it would be safe to say that I don't have much more than 100 lbs of force available.
> 
> I really need some way of applying a direct force to the carriage.  Possibly a line over a pulley at the tailstock end lifting a dead weight?I have a pulley mounted for the flexible conduit from my cross slide DRO already.


I like the simple pulley/  weight approach. But, if u have only 100lb or so at your disposal, then how come it cuts as quoted?
Surely it should have failed to cut.. anyway, regardless of computations, & anticipated requirements, it worked on your particular machine!
U must feel the need for more grunt!
BTW, in the process of updating a laptop to win10, from 7. On a 64 bit machine.
All done via MS, & a downloaded .iso file from them. All free. Just hope nothing goes wrong.


----------



## RJSakowski

Qtron said:


> I like the simple pulley/  weight approach. But, if u have only 100lb or so at your disposal, then how come it cuts as quoted?
> Surely it should have failed to cut.. anyway, regardless of computations, & anticipated requirements, it worked on your particular machine!
> U must feel the need for more grunt!
> BTW, in the process of updating a laptop to win10, from 7. On a 64 bit machine.
> All done via MS, & a downloaded .iso file from them. All free. Just hope nothing goes wrong.


The truth will come out when I do the test.  Based on the force required to turn the carriage crank in the past, 100 lbs. is probably sufficient.  I will see.
I am a bit disturbed by the fact that I can stall out the stepper with so little force and would like it to be higher.  I prefer to have more of an operating margin.  OTOH, I could just consider it to be a safety feature by stalling out and preventing a serious crash.


----------



## Qtron

RJSakowski said:


> The truth will come out when I do the test.  Based on the force required to turn the carriage crank in the past, 100 lbs. is probably sufficient.  I will see.
> I am a bit disturbed by the fact that I can stall out the stepper with so little force and would like it to be higher.  I prefer to have more of an operating margin.  OTOH, I could just consider it to be a safety feature by stalling out and preventing a serious crash.


yes  i like the safety idea,, TBH, i crashed my machine when learning threading


----------



## RJSakowski

deleted, dual post


----------



## RJSakowski

I did a bit of testing of the ELS.  

To assess the maximum force available, I have a bucket of lead wheel weights as a dead weight.  It is able to move against a 110 lb. force which is the capacity of the bucket.  At 105 lbs. it balked at a feed rate of 3.5 mm/rev. which corresponds to 1040 rpm on the stepper but was happy with 3 mm/rev. or 890 rpm.  At 110 lbs. the limit was 2.5 mm/rev or a stepper speed of 744 rpm. 

I doubt seriously that I would ever be running that fast.  Certainly not with metal.  I will thread at 170 rpm for the spindle speed and the coarsest inch thread I can cut is 8 tpi which would be 510 rpm on the stepper motor.  Even if I cut a metric 5 mm thread at 170 rpm, the stepper rpm would only be 800 rpm.


----------



## Qtron

RJSakowski said:


> I did a bit of testing of the ELS.
> 
> To assess the maximum force available, I have a bucket of lead wheel weights as a dead weight.  It is able to move against a 110 lb. force which is the capacity of the bucket.  At 105 lbs. it balked at a feed rate of 3.5 mm/rev. which corresponds to 1040 rpm on the stepper but was happy with 3 mm/rev. or 890 rpm.  At 110 lbs. the limit was 2.5 mm/rev or a stepper speed of 744 rpm.
> 
> I doubt seriously that I would ever be running that fast.  Certainly not with metal.  I will thread at 170 rpm for the spindle speed and the coarsest inch thread I can cut is 8 tpi which would be 510 rpm on the stepper motor.  Even if I cut a metric 5 mm thread at 170 rpm, the stepper rpm would only be 800 rpm.


does this mean Briney Eye was led astray by an Eng book?


----------



## RJSakowski

I found this online calculator.




__





						Lead Screw Torque and Force Calculator
					





					www.daycounter.com
				



The calculations agree fairly well with what I observed earlier today.


----------



## Qtron

RJSakowski said:


> I found this online calculator.
> 
> 
> 
> 
> __
> 
> 
> 
> 
> 
> Lead Screw Torque and Force Calculator
> 
> 
> 
> 
> 
> 
> www.daycounter.com
> 
> 
> 
> 
> The calculations agree fairly well with what I observed earlier today.


sorry re belated response,
Thankyou 4 the link, but re Torque(raise) = F*Dm/2*(L+u*PI*DM)/(PI*Dm-u*L) , Torque(lower)= F*Dm/2*(L-u*PI*DM)/(PI*Dm+u*L)
  definitions, terms, not found.
plugged in values left coefficient at 0.1, "compute", got ans of "Torque Raise" 0.512, "lower" of -0.156 but i don't get what that means, no units, just 'select units' in parentheses.


----------



## RJSakowski

Qtron said:


> sorry re belated response,
> Thankyou 4 the link, but re Torque(raise) = F*Dm/2*(L+u*PI*DM)/(PI*Dm-u*L) , Torque(lower)= F*Dm/2*(L-u*PI*DM)/(PI*Dm+u*L)
> definitions, terms, not found.
> plugged in values left coefficient at 0.1, "compute", got ans of "Torque Raise" 0.512, "lower" of -0.156 but i don't get what that means, no units, just 'select units' in parentheses.


If you dig into the site, they are talking about a vertical lead screw so gravity is taken into account.  Raising the load against gravity requires a driving (+) torque while lowering the load in a controlled fashion requires a braking (-) torque.  For our purposes, we need only look at the torque required to raise the load.


----------



## Qtron

RJSakowski said:


> If you dig into the site, they are talking about a vertical lead screw so gravity is taken into account.  Raising the load against gravity requires a driving (+) torque while lowering the load in a controlled fashion requires a braking (-) torque.  For our purposes, we need only look at the torque required to raise the load.


Thanks RJ.
BTW, & i normally wouldn't do this so freely, if U want a rotary divider WITH auto settable  X table feed for automated cutting of gears, I can highly recommend Steve Ward's version, his webpage not updated yet, as the improved version just completed.
Very smart , comprehensive, & well written s/w, using a PIC.
I just today got it going with an auto-tuning stepper driver from Leadshine.
8000 microsteps soooo smooth!
Www.worldofward.com


----------



## Qtron

RJSakowski said:


> If you dig into the site, they are talking about a vertical lead screw so gravity is taken into account.  Raising the load against gravity requires a driving (+) torque while lowering the load in a controlled fashion requires a braking (-) torque.  For our purposes, we need only look at the torque required to raise the load.


Hiya RJ hope ur OK, didnt hear back re Staves rotary table controller. (I didnt pay heaps for it!).
Am not his 'official' promoter, in case I gave that impression.
Finally Got cloughs els going, after long delay with led& key board delivery.


----------



## RJSakowski

Qtron said:


> Hiya RJ hope ur OK, didnt hear back re Staves rotary table controller. (I didnt pay heaps for it!).
> Am not his 'official' promoter, in case I gave that impression.
> Finally Got cloughs els going, after long delay with led& key board delivery.


Things are fine here.  Just settling finally into winter.  I hope you are far enough away from the wild fires to not eat too much smoke and ash.

I probably wouldn't have an interest in the rotary divider.  I already have a 6" 4th axis for my Tormach. It too is crazy smooth.  I don't recall what the driver microstep setting is but it increments in .001º or .36 seconds of arc.  My 12" RT is coarse by comparison at 5 second resolution.

I have designed a tool post for the Tormach so I can use it as a vertical CNC lathe.  The working length is comparatively short but I can, in theory, turn lengths of around 6".  Because of the R8 spindle, I wouldn't be able to run work through the spindle, a problem in common with the ER collet chucks.  The Tormach also doesn't have the capability of synchronizing the spindle to the other axes so threading in that mode is out but I have threadmilling capability so I'm covered there.  I also would need to get a small three or four jaw chuck to be able to turn work larger than the R8 collet capability.






Glad to hear the ELS is finally working for you.  I want to change out the LED's on mine for brighter ones but that isn't urgent.  When I ordered the display board, I actually ordered two so I have a spare.  I haven't ordered the LED's yet but it will be a quick fix when I finally get them in.  

I did some threading using the ELS a week or so ago.  A bunch of studs for fastening 1-2-3 blocks together. It sure was nice to be able to switch from feed to threading without messing with gears. It makes me wanting a VFD for the spindle though. Always another project. Actually, next on the list is to finish work on the auto release for the half nuts. The design has been done for some time and parts have been acquired. I just need to cut some metal. My expectation is that it should be repeatable to within a few thousandths.


----------



## Qtron

RJ, U've been busy! Thanks for sharing & posting the cad drawing too, very nice. Not sure re the need for a vertical lathe, horizontal seems more natural.
Tool post to be motorized?
 Probably wont  need 0.01° provided on Steves drive, let alone your precision quoted, except if driving a telescope! 
Smoke has hit us again, but not as bad, rain has doused some of the fires, ~ 100 still burning tho.
Smoke has travelled around the world now. 9-13 miles up!
So thats why the 1-2-3 blocks are Swiss cheese.
(I had asked at a shop, but no answers).
I have a VSD, but not fitted yet. Pain changing belt position on the motor end of the lathe. Upper belt OK.
Just a thought re feeds vs threading, if u use the els to provide the faster feed mode, that would add to the wear of the leadscrew c/f using the built in auto feed already provided on the lathe.

I am quite interested as to how U auto release the ½ nuts, and integrate that with cloughs els.
Cheers,


----------



## RJSakowski

The z axis moves rather than the tool.  Likewise, the x axis will move taking the place of a conventional cross feed.  The y axis wouldn't normally move but it could be used to access other tools.  The primary reason for doing this is to allow CNC turning with a piece of equipment  I already have.  The only requirement is to remember that because the work is moving rather than the tool, the G code is reversed.  If drilling  is required, drills can be mounted vertically on the table, ditto with boring bars.

I'm not sure of the origin of the holes in 1-2-3 blocks.  I tried digging into the history of them but was unable to find any information.  Like a lot of tools we have, they sprung from the necessity by a machinist and became commercialized.  The blocks that Tom Lipton, Ox Tools, made are a superior design.

I don't think that using the ELS will cause any more wear other than the fact that I would use it more.  I haven't used the power feed much in the past, largely because it was such a pain to be changing from feeding to threading and back.  Now that it is just the push of a button, I'll be more inclined to do so.  My plan is to cut power to my driver unless I plan to use the ELS which will stop the lead screw rotating when not in use.  This will cut down on gear case wear.

Re: the auto release, there is a discussion in post #2 in this thread. https://www.hobby-machinist.com/thr...ops-or-disengage-mechanism.79084/#post-675769
I decided to use a mechanism similar to a firearm or crossbow trigger rather than a simple mechanical action.  The seer is released by a solenoid (the rectangular box) and an extension spring will pull rod to the left and in turn, pull the pin on the half nut lever to release the half nut.  The rod is slotted to allow the half nuts to be disengaged manually.  Engaging the half nuts will cock the mechanism.  The solenoid will be activated by a microswitch or possibly an optical or Hall effect sensor.

Unfortunately, as Clough as discovered, there is no easy way to use the ELS to trigger the mechanism.  His design has the encoder adding counts whenever the spindle is turning, performing an occasional subtraction to avoid overflow. Using the ELS to stop z axis movement would require keeping the half nut engaged all the time.  Otherwise, positional information will be lost. I think it is possible to keep track of the total number of counts but it may require some sort of homing circuitry for the carriage.  We'll have to see what Clough comes up with.

Actually, it should be possible to keep the half nuts engaged at all times and use the enable and steering circuitry on the driver to to disengage and reverse the lead screw motor.


----------



## Qtron

RJSakowski said:


> The z axis moves rather than the tool.  Likewise, the x axis will move taking the place of a conventional cross feed.  The y axis wouldn't normally move but it could be used to access other tools.  The primary reason for doing this is to allow CNC turning with a piece of equipment  I already have.  The only requirement is to remember that because the work is moving rather than the tool, the G code is reversed.  If drilling  is required, drills can be mounted vertically on the table, ditto with boring bars.
> 
> I'm not sure of the origin of the holes in 1-2-3 blocks.  I tried digging into the history of them but was unable to find any information.  Like a lot of tools we have, they sprung from the necessity by a machinist and became commercialized.  The blocks that Tom Lipton, Ox Tools, made are a superior design.
> 
> I don't think that using the ELS will cause any more wear other than the fact that I would use it more.  I haven't used the power feed much in the past, largely because it was such a pain to be changing from feeding to threading and back.  Now that it is just the push of a button, I'll be more inclined to do so.  My plan is to cut power to my driver unless I plan to use the ELS which will stop the lead screw rotating when not in use.  This will cut down on gear case wear.
> 
> Re: the auto release, there is a discussion in post #2 in this thread. https://www.hobby-machinist.com/thr...ops-or-disengage-mechanism.79084/#post-675769
> I decided to use a mechanism similar to a firearm or crossbow trigger rather than a simple mechanical action.  The seer is released by a solenoid (the rectangular box) and an extension spring will pull rod to the left and in turn, pull the pin on the half nut lever to release the half nut.  The rod is slotted to allow the half nuts to be disengaged manually.  Engaging the half nuts will cock the mechanism.  The solenoid will be activated by a microswitch or possibly an optical or Hall effect sensor.
> 
> Unfortunately, as Clough as discovered, there is no easy way to use the ELS to trigger the mechanism.  His design has the encoder adding counts whenever the spindle is turning, performing an occasional subtraction to avoid overflow. Using the ELS to stop z axis movement would require keeping the half nut engaged all the time.  Otherwise, positional information will be lost. I think it is possible to keep track of the total number of counts but it may require some sort of homing circuitry for the carriage.  We'll have to see what Clough comes up with.
> 
> Actually, it should be possible to keep the half nuts engaged at all times and use the enable and steering circuitry on the driver to to disengage and reverse the lead screw motor.


So when  the LS is reversing, whats the Chuck/encoder doing? They would have to stay in sync to retain the 'start position' (better wording needed here, but hard to express!) Of the thread.
I am considering the Russian ELS 
By Oleg A., as it has cross slide X axis drive, whole threading process is automatic. 
See https://www.cnczone.com/forums/arduino/328770-cnc-posts.html
Thanks for the auto release link! And hint re Ox tools too.
Could u clarify re ''G-codes reversed'', maybe an example, if thats OK?


----------



## RJSakowski

I assume you are referring to my last paragraph or two.  I haven't thought this through as yet but the idea is that it should be possible to know what the spindle history and the lead screw history are by virtue of their encoders.  When reaching the end of a threading pass, the stepper driver would be disabled stopping the lead screw.  The spindle encoder count would continue to accumulate.  The cutter would be pulled out and the stepper driver reversed, reversing the lead screw and counting down the stepper encoder.  Meanwhile the stepper continues to accrue counts.  when the carriage has moved far enough to the right, it would be stopped, presumably by a user command.  The cutter would be positioned for the next cut.  Now the stepper encoder is way behind on counts so the controller would have to do an adjustment to resynchronize the counters, based on the count ratio for the required thread pitch.  This would be analogous to using the thread dial to resynchronize.

It seems kind of messy but something similar must be happening with the the Russian ELS, the German ELS, and with a CNC lathe.  It's all a matter of accounting.  The spindle is in effect controlling all the motion based on a preset program entered by the user.  

Re: the G code question, I sent a PM


----------



## Qtron

Bob, am Having trouble when on the pm page, problem is cant find how to get back here to this point on my mobile ph., or even with the PC.


----------



## RJSakowski

Qtron said:


> Bob, am Having trouble when on the pm page, problem is cant find how to get back here to this point on my mobile ph., or even with the PC.


You should have an envelope icon in the upper right corner of the page. If you click on that, it will open the conversations list.  Select the one you want to view.


----------



## RJSakowski

Qtron said:


> Bob, am Having trouble when on the pm page, problem is cant find how to get back here to this point on my mobile ph., or even with the PC.


On my phone, the icon is to the right of my personal icon.


----------



## Qtron

Sorry should clarify, by back here I mean back to main forum after viewing PM's.


----------



## Qtron

[QUOTE="RJSakowski
[/QUOTE]
Am fiddling with various settings, on cloughs control panel, does the power button on the 'led&key' board do anything on yours?
(All other buttons are working here).


----------



## RJSakowski

re: navigating HM Apparently, you figured it out.  I don't use my phone for viewing HM for the most part.  My thumbs are all thumbs when it comes to typing.


----------



## RJSakowski

The power button isn't activated.  I believe tha Clough had said so.  The settings button just brings up a "no settings" message.

It is interesting that the led key board allows control of the individual segments of the display.  The to extra buttons could allow a large number of options.  If the Power button was used to scroll through a menu and the settings button and/or the up down buttons used to change settings in the various menu items, it would be possible to use this display to set limit positions or trigger a reversal of the lead screw.

One possible scenario would be thread to a point and stop the lead screw.  the operator pushing the settings button after retracting the cutter would switch the direction of the lead screw, moving the carriage for another pass and there it would stop.  Pushing the button after setting the cutter would start the next pass.  But again, there is going to have to be some additional computation done in the controller to keep track of the synchronization.


----------



## Qtron

Hi Bob, I think he is gunna need extra display for add ons.
Did u have to alter his files to invert the step or enable lines?


----------



## RJSakowski

With some careful layout, he should be able to increase functionality with the existing display.  I would use the power button to step through various functions.  For each function, the other buttons could be redefined.  For example, if you wanted to set the left stop, push the button repeatedly until left stop was displayed then use the + and - buttons to set the value for that position.  Then move to the next function.  The settings button could be used to toggle as well.  There are a lot of possible combinations with 8 buttons.  Even more if you can decode two buttons pressed simultaneously.  Think of how keyboard functions are altered by pressing Ctrl , Shift, and Alt.

As to the Clough firmware settings, according to post #'s 124 and 126 in this thread, I have STEP and DIR active high and EN and ALARM active low.  ALARM may be wrong since I see no effect on the display when the driver faults.


----------



## Qtron

RJSakowski said:


> With some careful layout, he should be able to increase functionality with the existing display.  I would use the power button to step through various functions.  For each function, the other buttons could be redefined.  For example, if you wanted to set the left stop, push the button repeatedly until left stop was displayed then use the + and - buttons to set the value for that position.  Then move to the next function.  The settings button could be used to toggle as well.  There are a lot of possible combinations with 8 buttons.  Even more if you can decode two buttons pressed simultaneously.  Think of how keyboard functions are altered by pressing Ctrl , Shift, and Alt.
> 
> As to the Clough firmware settings, according to post #'s 124 and 126 in this thread, I have STEP and DIR active high and EN and ALARM active low.  ALARM may be wrong since I see no effect on the display when the driver faults.


Hi Bob!!
& For those interested: Non inverted steps are avail at pin "0" at J6/J8 connector on his "Boost" board.. Inverted is supplied from the (green) connector, the inversion happening via the simple transistor/buffer on his board.
Its probably best to either alter the  f/w, or, buy a flexible stepper driver, or insert another buffer to provide a non inverted outpu, if needed.
A non buffered output that leaves the board would be completely unprotected.

Unfortunately , for my setup, the sense of the step signal is not the issue, rather, it  is reaching the top speeds of his thread/ feed settings.
The only way to avoid the stalling, so far, is to increase the microstepping rate on the driver to 1600, a scenario i wanted to avoid with the associated loss of torque.
BTW,
I do hope Jon, AKA, Briney Eye comes back on-board - would be a real shame to not see the conclusions of all his hard work.
I haven't found ANY other  ELS with a touch screen!

Bob, the Stalling, as above, went away when I fitted the cog / gear required to drive the change gears/Norton gearbox/lead screw.
Its mass must be acting as a mechanical damper, so no problems now with top speed.
The CL57Y closed loop driver will be despatched as soon as Chinese NY ends, early Feb., so should be able to deliver the full 5 Amps that my stepper is capable of, hopefully torque should improve considerably up from my existing driver (3Amps max).


----------



## dfwilbanks

greenail said:


> I'm wondering what is state of the art for electronic lead screws these days and if anyone has advise based on implementing on on an import lathe?



Hello, I have not read the entire thread so if this has been suggested...  Try: https://www.youtube.com/channel/UCeKpbMimEGgLM_0tnghfoVw/videos


----------



## RJSakowski

dfwilbanks said:


> Hello, I have not read the entire thread so if this has been suggested...  Try: https://www.youtube.com/channel/UCeKpbMimEGgLM_0tnghfoVw/videos


This was suggested in post # 11 and has been the subject of much of the past eleven pages of this thread.


----------



## dfwilbanks

As I said, i didn't read the thread. I'm not intrested in an electronic lead screw but saw the topic and wanted to help the OP if possible. I watched the development of this one on youtube and liked how clough42 was doing his version.


----------



## RJSakowski

It is a long thread  and Clough42's effort has been the reason for a number of us implementing his design.


----------



## kb58

Mine (well, Clough42's) has been up and running for a few weeks. I've already used it a few times and, like having VFD speed control), it's very convenient for feed rates, never mind threading.


----------



## greenail

I'm digging into grblHAL to see if I can have a nicer jogging experience and eventually get G76 working.  If G76 works out my thinking is that grbl could be dumbed down into a nice ELS.  The benefit is that you could have the dumbed down mode for manual or semi-manual(threading, z fine feedrate control) operation and full CNC when you need it.

This shifts quite a lot of the work to your physical controls which could be customized easily.  You can see his lathe MPG here: 
	

	
	
		
		

		
			





I'm working on making a "toy" lathe mockup to do my testing on.


----------



## Qtron

greenail said:


> I'm digging into grblHAL to see if I can have a nicer jogging experience and eventually get G76 working.  If G76 works out my thinking is that grbl could be dumbed down into a nice ELS.  The benefit is that you could have the dumbed down mode for manual or semi-manual(threading, z fine feedrate control) operation and full CNC when you need it.
> 
> This shifts quite a lot of the work to your physical controls which could be customized easily.  You can see his lathe MPG here:
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> 
> I'm working on making a "toy" lathe mockup to do my testing on.


Far out! Thats super cool, but u got me: i must have missed something, who is ''his' lathe'' ?  Is there a link to the owner of this lovely beast?


----------



## greenail

the maintainer of grblHAL made that MPG which is called GRBL_MPG_DRO_BoosterPack.  The firmware and pcb stuff is on his github repo so you can make one!


----------



## Qtron

greenail said:


> the maintainer of grblHAL made that MPG which is called GRBL_MPG_DRO_BoosterPack.  The firmware and pcb stuff is on his github repo so you can make one!


Cheers, Greenail,
 i don't understand re GRBL, Got enuf trouble with arduino, lol
But found it,








						GitHub - terjeio/GRBL_MPG_DRO_BoosterPack: Tiva C BoosterPack for GRBL MPG/DRO
					

Tiva C BoosterPack for GRBL MPG/DRO. Contribute to terjeio/GRBL_MPG_DRO_BoosterPack development by creating an account on GitHub.




					github.com
				




any good, clear and basic overview re GRBL?


----------



## greenail

So, grbl was highly optimized for 8bit arduinos and has been very very successful for folks running real production machines.  Lately there has been quite a lot of development for faster processors with more memory which is exciting.  Bart Dring released open source hardware and a grbl port to the esp32 that I have been using for over  a year.  You can buy one of his boards on tindie.com or you can make your own (i've done both).   Bart's port supports trinamic drivers, laser mode, hobby servos with step/dir and a whole bunch more.  It is stable and because it uses the esp32 it can support much higher step rates so you can get smaller microstepping if you need it!  The 8 bit arduinos really struggled with >16 microstepping.  The great thing about he esp32 is that is is very inexpensive and easy to get.

grblHAL is another port of the classic grbl codebase which also supports esp32 but it supports a bunch of other boards and it is designed to make it easy for follks to add new processor architectures.  Generally the jogging on grbl has been sub par due to trying to squeeze it onto an old arduino with very limited memory.  The newer 32bit processors generally have much more memory available so more can be done to improve jogging (as you can see above by his MPG).  grblHAL also has some preliminary support for spindle sync and G76!  Finally terjeio is working on his own gcode sender that enables support for his grblHAL specific enhancements.  This seems the best fit to use to make a ELS since it already handles the spindle sync, step generation, acceleration motion control etc.  Again, it would also do full CNC if you needed it to.

generic grbl:









						Home · gnea/grbl Wiki
					

An open source, embedded, high performance g-code-parser and CNC milling controller written in optimized C that will run on a straight Arduino - Home · gnea/grbl Wiki




					github.com
				




a decent video:






bart's port:









						GitHub - bdring/Grbl_Esp32: A port of Grbl CNC Firmware for ESP32
					

A port of Grbl CNC Firmware for ESP32. Contribute to bdring/Grbl_Esp32 development by creating an account on GitHub.




					github.com
				




bart's blog (generally interesting)






						Buildlog.Net Blog
					

Lasers, CNC, Digital Fabrication, Design and Related




					www.buildlog.net


----------



## Qtron

greenail said:


> So, grbl was highly optimized for 8bit arduinos and has been very very successful for folks running real production machines.  Lately there has been quite a lot of development for faster processors with more memory which is exciting.  Bart Dring released open source hardware and a grbl port to the esp32 that I have been using for over  a year.  You can buy one of his boards on tindie.com or you can make your own (i've done both).   Bart's port supports trinamic drivers, laser mode, hobby servos with step/dir and a whole bunch more.  It is stable and because it uses the esp32 it can support much higher step rates so you can get smaller microstepping if you need it!  The 8 bit arduinos really struggled with >16 microstepping.  The great thing about he esp32 is that is is very inexpensive and easy to get.
> 
> grblHAL is another port of the classic grbl codebase which also supports esp32 but it supports a bunch of other boards and it is designed to make it easy for follks to add new processor architectures.  Generally the jogging on grbl has been sub par due to trying to squeeze it onto an old arduino with very limited memory.  The newer 32bit processors generally have much more memory available so more can be done to improve jogging (as you can see above by his MPG).  grblHAL also has some preliminary support for spindle sync and G76!  Finally terjeio is working on his own gcode sender that enables support for his grblHAL specific enhancements.  This seems the best fit to use to make a ELS since it already handles the spindle sync, step generation, acceleration motion control etc.  Again, it would also do full CNC if you needed it to.
> 
> generic grbl:
> 
> 
> 
> 
> 
> 
> 
> 
> 
> Home · gnea/grbl Wiki
> 
> 
> An open source, embedded, high performance g-code-parser and CNC milling controller written in optimized C that will run on a straight Arduino - Home · gnea/grbl Wiki
> 
> 
> 
> 
> github.com
> 
> 
> 
> 
> 
> a decent video:
> 
> 
> 
> 
> 
> 
> bart's port:
> 
> 
> 
> 
> 
> 
> 
> 
> 
> GitHub - bdring/Grbl_Esp32: A port of Grbl CNC Firmware for ESP32
> 
> 
> A port of Grbl CNC Firmware for ESP32. Contribute to bdring/Grbl_Esp32 development by creating an account on GitHub.
> 
> 
> 
> 
> github.com
> 
> 
> 
> 
> 
> bart's blog (generally interesting)
> 
> 
> 
> 
> 
> 
> Buildlog.Net Blog
> 
> 
> Lasers, CNC, Digital Fabrication, Design and Related
> 
> 
> 
> 
> www.buildlog.net


Thanks for all ur efforts here Greenail


----------



## luxige

RJSakowski said:


> In theory, a stepper has an infinite torque at zero rpm.  In practice, it is limited by the resistance and inductance of the stepper.The theoretical torque is inversely proportional to rpm, torque x rpm = constant.  The constant is dependent upon the geometry of the stepper and its electrical characteristics and will vary within motors of the same frame size and detent torque.  We used to use NEMA 17 motors from Oriental Motors and they have published torque/rpm curves for their motors.  The curves vary quite a bit between similar motors.
> 
> I made a decision on a motor for the 602 based in part on James' success with his hybrid stepper and that my Tormach steppers are 500 oz.-in.  I ordered a 600 oz.-in. hybrid stepper and driver kit, https://www.ebay.com/itm/233342928169 .    I plan on using 1:1 pulleys to drive the lead screw. I'm hoping that the inproved high speed response of the hybrid stepper will be sufficient.   My gut is telling me that the spindle motor will stall first.  If necessary, I can use the 2:1 gearing in the gear box to boost the torque.
> 
> My next concern is the power supply.  The stepper has three phase windings and a rated current of 5.8 amps/winding.  Does this mean that I need a power supply with a 20 amp rating?  At 48 volts, that's 1,000 watts. That seems a more than a bit large.  The Tormach has a 400 watt linear supply and is driving two 500 oz.-in steppers and one 700 oz.-on. stepper.



RJ, I see that the motor you chose runs at 200 steps/rev, while the one James used is 1000 steps/rev. Did this require a change to the code? I have zero experience coding and I don’t want to get into a project too deep for me to wade through!


----------



## ttabbal

luxige said:


> RJ, I see that the motor you chose runs at 200 steps/rev, while the one James used is 1000 steps/rev. Did this require a change to the code? I have zero experience coding and I don’t want to get into a project too deep for me to wade through!



There is a section of the code with well documented configuration. You can change the steps/rev there by changing one number. You can probably also enable microstepping with a switch on the controller to match the original.


----------



## RJSakowski

luxige said:


> RJ, I see that the motor you chose runs at 200 steps/rev, while the one James used is 1000 steps/rev. Did this require a change to the code? I have zero experience coding and I don’t want to get into a project too deep for me to wade through!


James is using a servo with a built in 1000 step encoder.  Yes, you will have to change some parameters in his code.  He explains how to this in part 10 of his video series.


----------



## RJSakowski

luxige said:


> RJ, I see that the motor you chose runs at 200 steps/rev, while the one James used is 1000 steps/rev. Did this require a change to the code? I have zero experience coding and I don’t want to get into a project too deep for me to wade through!


You can change various different parameters to achieve the desired output ratio depending on your particular situation.  I use a 2:1 gear reduction in my gear box to increase torque to the lead screw and changed a parameter accordingly.  For instance, I could change my srepper resolution to 400 steps/rev. or change the lead screw pitch from 16 to 32 with the same effect.


----------



## luxige

RJSakowski said:


> You can change various different parameters to achieve the desired output ratio depending on your particular situation.  I use a 2:1 gear reduction in my gear box to increase torque to the lead screw and changed a parameter accordingly.  For instance, I could change my srepper resolution to 400 steps/rev. or change the lead screw pitch from 16 to 32 with the same effect.



I think I roughly follow you, and I should be able to muddle through. The flashing and parameter setting parts of this project will be the big challenge for me.

Here's a combo I was looking at:





						YE Series 1 Axis Closed Loop Stepper CNC Kit 9.0 Nm(1274.76oz.in) Nema 34 Motor & Driver - 1-CL86Y-34HE46 STEPPERONLINE
					

YE Series 1 Axis Closed Loop Stepper CNC Kit 9.0 Nm(1274.76oz.in) Nema 34 Motor & Driver - 1-CL86Y-34HE46 - Closed Loop Stepper Kit - This CNC kit included: 1 x Closed Loop Stepper Driver 0-8.5A 20-80VAC/30-110VDC for Nema 34 Stepper Motor 1 x E Serie




					www.omc-stepperonline.com
				



Thoughts, anyone?

Yesterday I ordered Clough's interface board, a 1024p/rev encoder, Launchpad, 5v supply, display/control panel, Bud box. Here goes!
The last things to figure out are servo, driver, power supply, drivetrains for servo and encoder, nuts-n-bolts stuff.

One more point I'm a little lost on - will I need to source the connectors to hook stuff up to the interface board? From the pictures, it doesn't look like the male parts of the connectors are included…


----------



## kb58

Since this thread resurfaced, James posted a video several weeks ago on making the display box front panel from circuit board material (copper-covered fiberglass), and etching the printing. Turned out great, though it's unclear at this time whether he plans to make them available.


----------



## RJSakowski

luxige said:


> I think I roughly follow you, and I should be able to muddle through. The flashing and parameter setting parts of this project will be the big challenge for me.
> 
> Here's a combo I was looking at:
> 
> 
> 
> 
> 
> YE Series 1 Axis Closed Loop Stepper CNC Kit 9.0 Nm(1274.76oz.in) Nema 34 Motor & Driver - 1-CL86Y-34HE46 STEPPERONLINE
> 
> 
> YE Series 1 Axis Closed Loop Stepper CNC Kit 9.0 Nm(1274.76oz.in) Nema 34 Motor & Driver - 1-CL86Y-34HE46 - Closed Loop Stepper Kit - This CNC kit included: 1 x Closed Loop Stepper Driver 0-8.5A 20-80VAC/30-110VDC for Nema 34 Stepper Motor 1 x E Serie
> 
> 
> 
> 
> www.omc-stepperonline.com
> 
> 
> 
> 
> Thoughts, anyone?
> 
> Yesterday I ordered Clough's interface board, a 1024p/rev encoder, Launchpad, 5v supply, display/control panel, Bud box. Here goes!
> The last things to figure out are servo, driver, power supply, drivetrains for servo and encoder, nuts-n-bolts stuff.
> 
> One more point I'm a little lost on - will I need to source the connectors to hook stuff up to the interface board? From the pictures, it doesn't look like the male parts of the connectors are included…



Your stepper choice sounds OK.  You can correct somewhat for a undersized motor by changing the ratio if the stepper pulleys.  Clough uses a 3:1 ratio with his motor.  Stepper motors lose torque with increasing speed after a certain point determined buy the motor
Here is the torque curve for your motor.  https://www.omc-stepperonline.com/download/34HE46-6004D-E1000_Torque_Curve.pdf





As you can see, if you were operating with a 1:1 pulley set and at a lead screw speed of 300 rpm, you would have 420 N-cm of torque.  Changing to a 2:1 pulley arrangement , the stepper speed would have to be 600 rpm for the same lead screw speed and the stepper torque will be about 250 N-cm and the torque at the lead screw will be 500 N-cm for a 19% increase.  Going to 3:1, the stepper would run at 900 rpm@ 170 N-cm and x3 that would be 510N-cm or a 21% torque increase.

On the other end, most threading will most likely be done at low spindle speed and threads finer than 8 tpi.  so you will be operating at around the 150 rpm range.  Torque demands aren't all that great when threading as well.

You should have no trouble with the programming and flashing.  It went without incident for me.  The connectors for the interface board are included in Clough's kit.  He has a video on the assembly process. (part 8, I believe)


----------



## RJSakowski

kb58 said:


> Since this thread resurfaced, James posted a video several weeks ago on making the display box front panel from circuit board material (copper-covered fiberglass), and etching the printing. Turned out great, though it's unclear at this time whether he plans to make them available.


This is great idea. Easily done for someone without CNC capability.  You could jazz up the panel by putting backlighting in to illuminate the characters.

One issue with it though are the UP/DOWN buttons.  Unless someone has a 3D printer, they would be difficult to duplicate.  Also, the filament material he used is rather expensive for a single project.  I used round buttons made from Delrin and easily done on the lathe.  I also kept them centered on the switches on th3e display board.


----------



## luxige

RJSakowski said:


> Your stepper choice sounds OK.  You can correct somewhat for a undersized motor by changing the ratio if the stepper pulleys.  Clough uses a 3:1 ratio with his motor.  Stepper motors lose torque with increasing speed after a certain point determined buy the motor
> Here is the torque curve for your motor.  https://www.omc-stepperonline.com/download/34HE46-6004D-E1000_Torque_Curve.pdf
> View attachment 322758
> 
> As you can see, if you were operating with a 1:1 pulley set and at a lead screw speed of 300 rpm, you would have 420 N-cm of torque.  Changing to a 2:1 pulley arrangement , the stepper speed would have to be 600 rpm for the same lead screw speed and the stepper torque will be about 250 N-cm and the torque at the lead screw will be 500 N-cm for a 19% increase.  Going to 3:1, the stepper would run at 900 rpm@ 170 N-cm and x3 that would be 510N-cm or a 21% torque increase.
> 
> On the other end, most threading will most likely be done at low spindle speed and threads finer than 8 tpi.  so you will be operating at around the 150 rpm range.  Torque demands aren't all that great when threading as well.
> 
> You should have no trouble with the programming and flashing.  It went without incident for me.  The connectors for the interface board are included in Clough's kit.  He has a video on the assembly process. (part 8, I believe)



Thanks, RJ.
I've watched all his videos on this, but with eight-plus hours of content, and several extensive threads here, my brain filled up with info quickly. (Simply a matter of limited capacity I guess).

That's a very useful analysis of real-world torque needs. I think the 1200 oz-in may be overkill but I'm going to go with it. I can make room if I have to.
One thing I have going for me is that the gears in the quick change box that shift the leadscrew are not smashed up like most of the others, so I can just drive the feed shaft with the servo, and engage the leadscrew when needed. Two ratios, and each can run forward or reverse.


----------



## luxige

Well, I found another problem to ask for help with - power supply.
The driver I mentioned above is rated for 8.5A, recommended voltage is 48/60V. The Stepperonline only sells one power supply that’s in the ballpark, 48V, 8.3A (400W).








						400W 48V 8.3A 115/230V Switching Power Supply Stepper Motor CNC Router Kits
					

400W 48V 8.3A 115/230V Switching Power Supply Stepper Motor CNC Router Kits - This professional 400W 48V 8.



					www.omc-stepperonline.com
				



Close enough?

Or here’s one from Automation Technologies at 60V, 10A but over triple the cost.


			https://www.automationtechnologiesinc.com/products-page/switching-power-supply/60v10a-switching-cnc-power-supply-for-110vac/
		


Opinions appreciated...


----------



## ttabbal

I bet the cheaper one will be fine. The drivers usually have a setting for max current, so you could probably use that to set it. The actual current will depend on how much torque it needs if I remember right, so you would have to push it hard to get that high.


----------



## RJSakowski

Stepper drivers are protected against over voltage spikes and will shut down if the back emf exceed the maximum rated voltage for the driver.  To that end, it is recommended that when using a switching power supply, the supply voltage is less than 90% of the driver maximum rating.  It looks like your maximum voltage is 100 volts d.c. anything less than 90 volts should work.  

The other factor is the dependence of motor torque on voltage.  This is evident in the torque curve above.    Generally, you will get better performance with a higher voltage.  On the other hand, stepper motors tend to be more noisy with higher driving voltage and they can overheat if pushed too hard.  There is a discussion of power supply selection in post 247.

I would think that the 48 volt supply should work .  A 60 volt supply would be a better choice because of the greater available torque but you can achieve the same or better performance by using a 2:1 pulley reduction on the stepper.  Most switching power supplies have a voltage adjust pot where you can tweak the output voltage.  Mine are all around +/- 10%.  Id that is the case, you would be able to increase the supply voltage to as much as 53 volts.


----------



## luxige

ttabbal said:


> I bet the cheaper one will be fine. The drivers usually have a setting for max current, so you could probably use that to set it. The actual current will depend on how much torque it needs if I remember right, so you would have to push it hard to get that high.



Thank you!


----------



## luxige

RJSakowski said:


> Stepper drivers are protected against over voltage spikes and will shut down if the back emf exceed the maximum rated voltage for the driver.  To that end, it is recommended that when using a switching power supply, the supply voltage is less than 90% of the driver maximum rating.  It looks like your maximum voltage is 100 volts d.c. anything less than 90 volts should work.
> 
> The other factor is the dependence of motor torque on voltage.  This is evident in the torque curve above.    Generally, you will get better performance with a higher voltage.  On the other hand, stepper motors tend to be more noisy with higher driving voltage and they can overheat if pushed too hard.  There is a discussion of power supply selection in post 247.
> 
> I would think that the 48 volt supply should work .  A 60 volt supply would be a better choice because of the greater available torque but you can achieve the same or better performance by using a 2:1 pulley reduction on the stepper.  Most switching power supplies have a voltage adjust pot where you can tweak the output voltage.  Mine are all around +/- 10%.  Id that is the case, you would be able to increase the supply voltage to as much as 53 volts.



Thanks again!
Yeah, I pretty much figured I would gear up the torque. No particular need to race the carriage up and down the bed.
I have a feeling this motor will give me plenty of performance headroom, and if not, I can change the reduction with another pulley and belt.


----------



## RJSakowski

luxige said:


> Thanks again!
> Yeah, I pretty much figured I would gear up the torque. No particular need to race the carriage up and down the bed.
> I have a feeling this motor will give me plenty of performance headroom, and if not, I can change the reduction with another pulley and belt.


At a maximum of 5,000 rpm and a pitch of 8 tpi, even at a 3:1 ratio,  that's still 147 ipm.  The maximum feed rate for the Clough  system is 5mm/rev. if you use the metric thread mode.  It would be crazy to run at that setting at my maximum spindle speed of 2400 rpm.  Actually, I would be at twice the maximum stepper rpm anyway.


----------



## greenail

RJSakowski said:


> Your stepper choice sounds OK.  You can correct somewhat for a undersized motor by changing the ratio if the stepper pulleys.  Clough uses a 3:1 ratio with his motor.  Stepper motors lose torque with increasing speed after a certain point determined buy the motor
> Here is the torque curve for your motor.  https://www.omc-stepperonline.com/download/34HE46-6004D-E1000_Torque_Curve.pdf
> View attachment 322758
> 
> As you can see, if you were operating with a 1:1 pulley set and at a lead screw speed of 300 rpm, you would have 420 N-cm of torque.  Changing to a 2:1 pulley arrangement , the stepper speed would have to be 600 rpm for the same lead screw speed and the stepper torque will be about 250 N-cm and the torque at the lead screw will be 500 N-cm for a 19% increase.  Going to 3:1, the stepper would run at 900 rpm@ 170 N-cm and x3 that would be 510N-cm or a 21% torque increase.
> 
> On the other end, most threading will most likely be done at low spindle speed and threads finer than 8 tpi.  so you will be operating at around the 150 rpm range.  Torque demands aren't all that great when threading as well.
> 
> You should have no trouble with the programming and flashing.  It went without incident for me.  The connectors for the interface board are included in Clough's kit.  He has a video on the assembly process. (part 8, I believe)




That chart doesn't make sense for a 9Nm stepper.  that is showing .7Nm at peak?

anyway, I'm using a 2.2Nm hybrid stepper direct drive on a 2mm pitch leadscrew and it happily stalls out my spindle motor before it faults.  I've threaded hardened shafts and the insert is more of a problem than the stepper.  I'd guess that Clough's firmware would also stop driving the lead screw when the spindle stopped.  I guess if you are taking huge cuts and or cutting huge threads you might need such a beast but for < 2mm pitch I can't see much need to go bigger.  Are you planning on cutting acme threads or something?

Finally consider that motors don't just start stop instantly, there should be an acceleration curve (or trapezoid).  I doubt the controller can compensate for crazy spindle speeds and the sync issues decelerating at the end of your thread.  The larger the motor and the more inertia it has which makes that acceleration curve flatter.  at some point it can't keep up no matter how much torque you have unlike a gear train which just breaks when you run it too fast.  everything is a trade off


----------



## Qtron

Null post


----------



## greenail

greenail said:


> That chart doesn't make sense for a 9Nm stepper.  that is showing .7Nm at peak?
> 
> anyway, I'm using a 2.2Nm hybrid stepper direct drive on a 2mm pitch leadscrew and it happily stalls out my spindle motor before it faults.  I've threaded hardened shafts and the insert is more of a problem than the stepper.  I'd guess that Clough's firmware would also stop driving the lead screw when the spindle stopped.  I guess if you are taking huge cuts and or cutting huge threads you might need such a beast but for < 2mm pitch I can't see much need to go bigger.  Are you planning on cutting acme threads or something?
> 
> Finally consider that motors don't just start stop instantly, there should be an acceleration curve (or trapezoid).  I doubt the controller can compensate for crazy spindle speeds and the sync issues decelerating at the end of your thread.  The larger the motor and the more inertia it has which makes that acceleration curve flatter.  at some point it can't keep up no matter how much torque you have unlike a gear train which just breaks when you run it too fast.  everything is a trade off



math   decimal go too far....  chart good!  still odd it only goes to 7Nm...


----------



## greenail

Qtron said:


> RJ, I see that the motor you chose runs at 200 steps/rev, while the one James used is 1000 steps/rev. Did this require a change to the code? I have zero experience coding and I don’t want to get into a project too deep for me to wade through!



likely micro stepping steps, most steppers come in either 200 or 400 unless they happen to be super special and 3 phase, or come with a gear box.

total steps = micro steps * motor steps (200)


----------



## luxige

greenail said:


> likely micro stepping steps, most steppers come in either 200 or 400 unless they happen to be super special and 3 phase, or come with a gear box.
> 
> total steps = micro steps * motor steps (200)



Thanks for the input!
Yeah, I was confusing the 1000 lines of the built in encoder with the motor steps.


----------



## greenail

luxige said:


> Thanks for the input!
> Yeah, I was confusing the 1000 lines of the built in encoder with the motor steps.



I've not read the docs for that device but one additional config confusion thing is also the quadrature mode for the "decoder", assuming the highest resolution algorithm for quadrature you get 4 signals per encoder line.  It could be 2x or 1x though.  HomoFaciens has a good video on how it works here.   PPR (or LPR) is the line count, counts per revolution CPR is the quadrature counts per revolution (4xPPR in 4x decoding mode).  
You can actually make a very decent optical encoder pretty easily with about 0.50 worth of parts but it will not likely be high enough resolution for this application.  The "dexter" robot has a pretty interesting 3d printed encoder setup that uses a combination of quadrature encoding and sin/cos encoding of the analog photo diode signal.  

I've played with a similar approach using hall effect sensor arrays and refrigerator magnet strips for linear position encoding which I should take back up again (it has been sitting on the shelf for a year now ) since it would make a fairly useful and inexpensive DRO.


----------



## RJSakowski

greenail said:


> That chart doesn't make sense for a 9Nm stepper.  that is showing .7Nm at peak?
> 
> anyway, I'm using a 2.2Nm hybrid stepper direct drive on a 2mm pitch leadscrew and it happily stalls out my spindle motor before it faults.  I've threaded hardened shafts and the insert is more of a problem than the stepper.  I'd guess that Clough's firmware would also stop driving the lead screw when the spindle stopped.  I guess if you are taking huge cuts and or cutting huge threads you might need such a beast but for < 2mm pitch I can't see much need to go bigger.  Are you planning on cutting acme threads or something?
> 
> Finally consider that motors don't just start stop instantly, there should be an acceleration curve (or trapezoid).  I doubt the controller can compensate for crazy spindle speeds and the sync issues decelerating at the end of your thread.  The larger the motor and the more inertia it has which makes that acceleration curve flatter.  at some point it can't keep up no matter how much torque you have unlike a gear train which just breaks when you run it too fast.  everything is a trade off


It's 700 N-cm or 7 N-m.  A stepper torque is highest at zero rpm.  Stepper torque is also dependent on driver voltage.  I believe the literature says that driver is capable of running a 100 volt supply.

The question at hand was how much torque does the OP need.  In my experience, I would have no problem cutting any threads. The problem may come when using power feed for roughing cuts.  However, I wouldn't be making a roughing cut at 2400 rpm.  For one, my  motor would stall out would stall out.  

As to the acceleration and deceleration,  the stepper is synced to the spindle and as long as the spindle is turning, the stepper is turning.  When cutting metric threads on an imperial lathe or vice versa and you are forced to stop the motor and reverse for the next pass, the lathe motor inertia should overide any acce4leration/deceleration issues with the stepper.  This may not be true if you have clutch and mechanical brake on the lathe though.


----------



## RJSakowski

I believe that Clough used a hybrid servo on his lathe which is why he set the resolution at 1000.  The encoder on the hybrid steppers performs a different function.  It monitors lost steps and attempts to inject additional steps to bring the stepper back in sync.  Additionally, there is a user selectable error limuit which, if exceeded, shuts the driver down requiring a power on reboot.  The default setting on my driver was 1000 encoder steps or one revolution of the stepper motor.  When threading, an error like 999 counts would be excessive but I don't believe that I would encounter that situation.  Using power feed, loss of sync isn't an issue.  Loss of steps would be due to an insufficient force meeting a insurmountable object and shutting down the drive could be viewed as a good to have safety feature.

I set my ELS up with separate power switches for the ELS control and the stepper drive.  This allows me to power down the drive while still having the ELS operating.  Thus, my lead screw isn't turning unless I want it to turn.  It's also more convenient for rebooting the stepper drive.


----------



## luxige

greenail said:


> I've not read the docs for that device but one additional config confusion thing is also the quadrature mode for the "decoder", assuming the highest resolution algorithm for quadrature you get 4 signals per encoder line.  It could be 2x or 1x though.  HomoFaciens has a good video on how it works here.   PPR (or LPR) is the line count, counts per revolution CPR is the quadrature counts per revolution (4xPPR in 4x decoding mode).
> You can actually make a very decent optical encoder pretty easily with about 0.50 worth of parts but it will not likely be high enough resolution for this application.  The "dexter" robot has a pretty interesting 3d printed encoder setup that uses a combination of quadrature encoding and sin/cos encoding of the analog photo diode signal.
> 
> I've played with a similar approach using hall effect sensor arrays and refrigerator magnet strips for linear position encoding which I should take back up again (it has been sitting on the shelf for a year now ) since it would make a fairly useful and inexpensive DRO.



Thanks for the reference, I’ll check it out.


----------



## luxige

RJSakowski said:


> I believe that Clough used a hybrid servo on his lathe which is why he set the resolution at 1000.  The encoder on the hybrid steppers performs a different function.  It monitors lost steps and attempts to inject additional steps to bring the stepper back in sync.  Additionally, there is a user selectable error limuit which, if exceeded, shuts the driver down requiring a power on reboot.  The default setting on my driver was 1000 encoder steps or one revolution of the stepper motor.  When threading, an error like 999 counts would be excessive but I don't believe that I would encounter that situation.  Using power feed, loss of sync isn't an issue.  Loss of steps would be due to an insufficient force meeting a insurmountable object and shutting down the drive could be viewed as a good to have safety feature.
> 
> I set my ELS up with separate power switches for the ELS control and the stepper drive.  This allows me to power down the drive while still having the ELS operating.  Thus, my lead screw isn't turning unless I want it to turn.  It's also more convenient for rebooting the stepper drive.



That’s a very clear explanation.
BTW, I ordered the motor, driver, and power supply last night. I switched gears again and got the Automation Technologies stuff. The Stepperonline shipping charge was going to nearly double the cost and they have a week delay now for a holiday. For about 20% more, I’ll have it much sooner and, and I suspect, better support.
Also got motor cable, a variety of connectors, IEC power cord, case fan, etc. I’ll wait until I lay it all out before getting an enclosure.
Today, I shop pulleys and belts.

One odd thing about the lathe. I finally got around to measuring the leadscrew and it is imperial! The feed rack and pinion, and cross slide screw, are metric. (They have inch “conversion” dials, approximately 4” per turn, with a small accumulated error).
This explains the odd collection of bushings and couplings that attach the leadscrew to the QCGB. I guess a shop converted it in house. If so, they did a nice job with the half-nuts, doesn’t look bodged up at all. Or maybe it was a factory option?
Anyway, the leadscrew is 4tpi and 1-1/8” dia. Half-nuts are bronze.
The feed shaft has a single spline, and drives much more freely.


----------



## luxige

Fiiiinally got all the parts in.
There’s a new development that brings up a problem. Of course.

My initial plan was to mount the hybrid servo motor within the lathe bed, similar to Gus' idea (as posted in a Github issue), and drive the gearbox input with the servo via a M5 belt. This would let me put an idler on the change gear banjo and I'd have an easy way to adjust the belt tension by moving the idler up or down. But two things interfere. Most importantly, the QCGB is so badly damaged that I only have a couple of working ratios out of over a hundred possibilities. The simplest one is 32:15, gearbox input:leadscrew. I was worried that adding those factors to the numerator and denominator calcs might be too much. (James had advised Gus against using his 120 and 127-tooth change gears between servo and leadscrew, because the math might be too much heavy lifting for the microcontroller).   Then I found that my initial measurements were wrong, and placing the motor inside the lathe bed would be extremely challenging, so it's all moot anyway.
So I decided to add an extension to the tailstock end of the leadscrew and drive it from there. I gutted the gearbox, leaving only the gears which connect the leadscrew and feed shaft. They run 1:1.
Here's the problem - the feed shaft is geared within the carriage apron to a ratio of (approximately) 19 turns per inch of carriage travel. So the leadscrew and feed shaft produce different rates of carriage movement when turned at any given stepper value. I don't want to abandon the feed shaft and do feeds with the 4TPI Acme screw, so I'm trying to figure out the best way to use both. I have a few ideas.
Solution 1: Alter the Feed formula by 19/4ths. Actually, I'd just round it off to a factor of 5 in the numerator, that's only a 5% error in feed rate.
Solution 2: Define a new variable (say, "feedshaftrate") to replace the leadscrew TPI variable in the Feed formula. Set the new variable to 19 TPI and I'm done. However, I have Zero coding experience, so I'm not sure I'm up to it.
Solution 3: Change the Feed tables, so the the value displayed on the LED panel is low by a factor of 5. So for example, selecting .010"/rev (as displayed) would actually be telling the controller to feed at .050"/rev, but the slower feed shaft rate would actually result in a feed of .0105. Close enough. I'd have to add some rows to the table at the top end to get the faster speeds, and delete the slowest speeds. Again, Absolute Zero coding experience.
Okay, what would you do? Am I missing an easier answer? Any input will be appreciated, so thanks in advance.


----------



## ttabbal

I submitted a change to him that allows different feed and threading calculations. My PM1127 has the same issue. Note that the feed for the cross slide is different, but I decided having relative control was good enough. I rarely care exactly what the feed rate is, only that I can adjust it consistently. Particularly on the cross slide. So I make it correct for the carriage, and live with it being off for that one. 

It looks like he hasn't merged my pull request into the main repository. No big deal, here's my version with that change. If you need help adjusting it for your setup, let me know and I'll see what I can do. 

https://github.com/travistabbal/electronic-leadscrew/tree/travis/master


----------



## luxige

Thanks very much, Travis!
I only have time right now to glance at it, but I will look over your changes carefully later today. I think you may have saved my bacon!
Btw, the PM1127 was very close to being in my shopping cart when I came across this 12x36.


----------



## Suzuki4evr

Dabbler said:


> There's a nice ELS from Germany that they call an Electronic Lead Screw - Stefan Gotteseinter did a review of it on his youtube channel.  They will have a complete English manual available early this year. It leaves manual operation untouched and is DIY for the home machinist.


Hallo Dabbler. I am totally off topic,but it's nice to see your icon again, I haven't seen it in a long time, or am I wrong?


----------



## luxige

ttabbal said:


> I submitted a change to him that allows different feed and threading calculations. My PM1127 has the same issue. Note that the feed for the cross slide is different, but I decided having relative control was good enough. I rarely care exactly what the feed rate is, only that I can adjust it consistently. Particularly on the cross slide. So I make it correct for the carriage, and live with it being off for that one.
> 
> It looks like he hasn't merged my pull request into the main repository. No big deal, here's my version with that change. If you need help adjusting it for your setup, let me know and I'll see what I can do.
> 
> https://github.com/travistabbal/electronic-leadscrew/tree/travis/master



Travis, I have applied a version of your changes, which compiled after a couple of false starts. There's a new problem I think you may be able to help with - I can't get the build to flash. There is a connection error, Connection to XDS110 failed, Error 260 @ 0_0
After scouring the support documentation, it seems maybe I need to update the firmware or update the board serial number. This is done through a utility within CCS called xdsdfu. However, I can't get that to run.
Any ideas?


----------



## luxige

Okay, never mind the above, but stay tuned for the new problem! 
I eventually managed to uninstall Code Composer, and re-download and install it (after several failed attempts). When I flashed the build, I got a dialog box with the option to update XDS110 firmware. I did so at last.

This all took about six hours of downloading, rebooting, installing, etc. but seemed to do the trick. The build was flashed to the Launchpad, or at least I think it was. The Debug console seemed to look about like the examples in the video, but I don't know much about what I'm looking at or looking for.

The code ran, stopped at the breakpoint as expected, I hit Resume... and nothing. The display panel stays dormant, although when I click on some of the buttons a tiny LED to the left of the digits lights up briefly. But only occasionally, most of the time it seems dead. Turning the encoder shaft does not produce any reaction. 

I have no idea whether the display board is really dead, or if the program is not running. Or both. 
Frankly, I'm just heartsick about this thing. I've spent so many hours (and way more money than I should be throwing around) to deal with a steady stream of setbacks. And now it's looking like a dead end.

How should I go about troubleshooting? Thanks in advance for your advice.


----------



## FLguy

I have coming, due any day, Rocketronics ELS 4 Basic with conversion pack, Servo L. This goes on a PM 1127 VF-LB lathe. Lead screw motor is Hybrid-Schrittmotor ES-M23480 MIT Encoder. X-axis is, Hybrid Stepper Motor 60BYGH450D-02. Encoder, PIB408-400Z.
  X-axis motor mounting off back of carriage. Using a 1:1 ratio on encoder. Using the lathes spindle gear to a Acetal gear I need to make. 
  I got so darn mad at the change gear set up on this lathe for the last time about a month ago I said never again. So that evening was spent doing a lot of looking at different ELS sytems and over a months time I went with a really well thought out sytem by Rocketronics In Germany. Deivery thru customs, ports and what ever else has taken 1 month so far. Might get it within the next week or 2 as DHL has not handed it over to USPS for delivery. This has been a fun project to-date.


----------



## greenail

FLguy said:


> I have coming, due any day, Rocketronics ELS 4 Basic with conversion pack, Servo L. This goes on a PM 1127 VF-LB lathe. Lead screw motor is Hybrid-Schrittmotor ES-M23480 MIT Encoder. X-axis is, Hybrid Stepper Motor 60BYGH450D-02. Encoder, PIB408-400Z.
> X-axis motor mounting off back of carriage. Using a 1:1 ratio on encoder. Using the lathes spindle gear to a Acetal gear I need to make.
> I got so darn mad at the change gear set up on this lathe for the last time about a month ago I said never again. So that evening was spent doing a lot of looking at different ELS sytems and over a months time I went with a really well thought out sytem by Rocketronics In Germany. Deivery thru customs, ports and what ever else has taken 1 month so far. Might get it within the next week or 2 as DHL has not handed it over to USPS for delivery. This has been a fun project to-date.



please report on this when you get it, that ELS looks very nice!


----------



## kb58

luxige said:


> Okay, never mind the above, but stay tuned for the new problem!
> I eventually managed to uninstall Code Composer, and re-download and install it (after several failed attempts). When I flashed the build, I got a dialog box with the option to update XDS110 firmware. I did so at last.
> 
> This all took about six hours of downloading, rebooting, installing, etc. but seemed to do the trick. The build was flashed to the Launchpad, or at least I think it was. The Debug console seemed to look about like the examples in the video, but I don't know much about what I'm looking at or looking for.
> 
> The code ran, stopped at the breakpoint as expected, I hit Resume... and nothing. The display panel stays dormant, although when I click on some of the buttons a tiny LED to the left of the digits lights up briefly. But only occasionally, most of the time it seems dead. Turning the encoder shaft does not produce any reaction.
> 
> I have no idea whether the display board is really dead, or if the program is not running. Or both.
> Frankly, I'm just heartsick about this thing. I've spent so many hours (and way more money than I should be throwing around) to deal with a steady stream of setbacks. And now it's looking like a dead end.
> 
> How should I go about troubleshooting? Thanks in advance for your advice.


I recommend starting from Square 1. You've reinstalled Code Composer, good. Next, download Clough42's version that you know works, and don't mess with it. Build it, flash it to the board, and see if you at least get the display working again.  If you have any problems, go back and carefully follow his video, which steps through the entire build process. Once it's back up and running, then you can go in and change the constants to match your setup. Save off a copy of that.

ONLY THEN should you consider making additional changes. It's unlikely you broke anything permanently (assuming that you aren't leaving something out of the story!).


----------



## kb58

duplicate


----------



## RJSakowski

luxige said:


> Okay, never mind the above, but stay tuned for the new problem!
> I eventually managed to uninstall Code Composer, and re-download and install it (after several failed attempts). When I flashed the build, I got a dialog box with the option to update XDS110 firmware. I did so at last.
> 
> This all took about six hours of downloading, rebooting, installing, etc. but seemed to do the trick. The build was flashed to the Launchpad, or at least I think it was. The Debug console seemed to look about like the examples in the video, but I don't know much about what I'm looking at or looking for.
> 
> The code ran, stopped at the breakpoint as expected, I hit Resume... and nothing. The display panel stays dormant, although when I click on some of the buttons a tiny LED to the left of the digits lights up briefly. But only occasionally, most of the time it seems dead. Turning the encoder shaft does not produce any reaction.
> 
> I have no idea whether the display board is really dead, or if the program is not running. Or both.
> Frankly, I'm just heartsick about this thing. I've spent so many hours (and way more money than I should be throwing around) to deal with a steady stream of setbacks. And now it's looking like a dead end.
> 
> How should I go about troubleshooting? Thanks in advance for your advice.


This is always an annoying situation.  There are so many components that it is difficult to diagnose the cause of the failure.  When I bought my display board, I bought an extra.  Fortunately, both worked.  Is it possible for you to connect it to an Arduino? This would parse out the display from the rest of the system.  It is possible that there is a problem with one of the other boards.  ESD would be a likely culprit.  Also double check that the switches are all set correctly and that wiring is correct. 

I doubt that the encoder or the stepper controller outputs are at fault.  The problem would either be the display itself or the Launchpad from a hardware standpoint or from the Code composer or firmware.  Perhaps contacting Clough is in order.  He may have some suggestions.


----------



## ttabbal

luxige said:


> How should I go about troubleshooting? Thanks in advance for your advice.



Well, that's a wild ride for sure. I think the best thing to do here is start at the beginning. I think the board is working if you have the breakpoint hitting. So at least we have a good idea that the launchpad board itself and the onboard programmer work. I would remove anything connected to it and run via USB for a bit while sorting things out. You will need to set the power jumpers to the default positions to power the board from USB. 

From there, use one of the launchpad board examples that come with the IDE and make sure you can do a build/flash/run with known good setup. Something super simple like blink an LED is plenty. Flash it to the Launchpad, not just run from memory. We want to check that part of the board/chip as well. 

If that works, triple check all the jumpers and switches. I don't think they are necessary for the display board to work, but it's a good place to start. Set them as directed by Clough42. From here, you can connect the PCB from him for power and interfacing. Tripple check that it's lined up properly. It CAN be installed one pin off, for example. Disconnect everything else though. Now check with the existing program for the LED blink or whatever. We want to be sure the Launchpad is getting power and working still. 

Now add the display board. How are you wiring it? I found that how it's connected matters a great deal and it's pretty easy to get interference and mess up the display etc.. It doesn't damage anything, but it also doesn't work right.  Start with short jumper wires direct to the interface board. No more than 6" or so. If that works, we can start looking at wiring. 

With electronics/programming, troubleshooting is usually start from the simplest setup and build up one part at a time until it breaks. Now you know what is wrong and can look at fixing it. Lets get the display working and we can start on the mechanical bits.


----------



## luxige

kb58 said:


> I recommend starting from Square 1. You've reinstalled Code Composer, good. Next, download Clough42's version that you know works, and don't mess with it. Build it, flash it to the board, and see if you at least get the display working again.  If you have any problems, go back and carefully follow his video, which steps through the entire build process. Once it's back up and running, then you can go in and change the constants to match your setup. Save off a copy of that.
> 
> ONLY THEN should you consider making additional changes. It's unlikely you broke anything permanently (assuming that you aren't leaving something out of the story!).



Thanks for your input! 
I have followed through the video carefully, step by step, many times. It's an old friend/nemesis at this point. I'll continue to refer to it as I keep working on this, though.

I'll follow your advice about trying a known good code.

Thinking back on it, there is one more detail that may apply - I had some trouble desoldering the top-mounted header pins. Maybe I damaged the board. If it's something that simple, would that prevent the controller and peripherals from working? (When I turn the rotary encoder shaft, there is no response from the servo).


----------



## luxige

RJSakowski said:


> This is always an annoying situation.  There are so many components that it is difficult to diagnose the cause of the failure.  When I bought my display board, I bought an extra.  Fortunately, both worked.  Is it possible for you to connect it to an Arduino? This would parse out the display from the rest of the system.  It is possible that there is a problem with one of the other boards.  ESD would be a likely culprit.  Also double check that the switches are all set correctly and that wiring is correct.
> 
> I doubt that the encoder or the stepper controller outputs are at fault.  The problem would either be the display itself or the Launchpad from a hardware standpoint or from the Code composer or firmware.  Perhaps contacting Clough is in order.  He may have some suggestions.



Thanks for your reply!
I don't have any means to test the display board separately. I may have damaged it when I desoldered the stock header pins, see my reply above to kb58.

I was pretty careful about static mitigation. But, who knows? I am sure the little switches are properly set, but of course I will be rechecking that and everything else. My first step  will be to check all my cables/connectors for continuity. And verify I didn't switch a pin.

I will open an issue on Github and send an email to James.


----------



## luxige

ttabbal said:


> Well, that's a wild ride for sure. I think the best thing to do here is start at the beginning. I think the board is working if you have the breakpoint hitting. So at least we have a good idea that the launchpad board itself and the onboard programmer work. I would remove anything connected to it and run via USB for a bit while sorting things out. You will need to set the power jumpers to the default positions to power the board from USB.
> 
> From there, use one of the launchpad board examples that come with the IDE and make sure you can do a build/flash/run with known good setup. Something super simple like blink an LED is plenty. Flash it to the Launchpad, not just run from memory. We want to check that part of the board/chip as well.
> 
> If that works, triple check all the jumpers and switches. I don't think they are necessary for the display board to work, but it's a good place to start. Set them as directed by Clough42. From here, you can connect the PCB from him for power and interfacing. Tripple check that it's lined up properly. It CAN be installed one pin off, for example. Disconnect everything else though. Now check with the existing program for the LED blink or whatever. We want to be sure the Launchpad is getting power and working still.
> 
> Now add the display board. How are you wiring it? I found that how it's connected matters a great deal and it's pretty easy to get interference and mess up the display etc.. It doesn't damage anything, but it also doesn't work right.  Start with short jumper wires direct to the interface board. No more than 6" or so. If that works, we can start looking at wiring.
> 
> With electronics/programming, troubleshooting is usually start from the simplest setup and build up one part at a time until it breaks. Now you know what is wrong and can look at fixing it. Lets get the display working and we can start on the mechanical bits.



Thanks for your advice, that's very helpful and clear!
I think that trying a sample program is a great idea. Browsing the directory, I don't see any sample program files. Where should I be looking?

Jumpers and switches are all correct, I'm sure, but of course I will recheck. I'll check all my cables as well.
the display board is connected via short sections of ribbon cable to aviation-style round connectors, with a shielded cable in between. Right now it's a bench setup, and I think I kept the noisy stuff away from the data pretty well. But I'll make up a short test cable.

As noted above, I think it's possible I damaged the display board when desoldering. Do you think that would prevent the program from responding to the rotary encoder input?


----------



## ttabbal

luxige said:


> Thanks for your advice, that's very helpful and clear!
> I think that trying a sample program is a great idea. Browsing the directory, I don't see any sample program files. Where should I be looking?
> 
> Jumpers and switches are all correct, I'm sure, but of course I will recheck. I'll check all my cables as well.
> the display board is connected via short sections of ribbon cable to aviation-style round connectors, with a shielded cable in between. Right now it's a bench setup, and I think I kept the noisy stuff away from the data pretty well. But I'll make up a short test cable.
> 
> As noted above, I think it's possible I damaged the display board when desoldering. Do you think that would prevent the program from responding to the rotary encoder input?




It looks like the installer defaults to C:\ti\tutorial. 

There is some documentation here that might be helpful getting things going.  http://www.ti.com/lit/an/spra766/spra766.pdf?ts=1590694503172

I wouldn't think that damaging the solder pads would mess up the ability to run the encoder and servo. Though it's hard to debug issues with those without the screen. You might be able to run connected to the debugger and use breakpoints to see the changes in the encoder. The trick here is that a single wire mixed up can make it not respond, but you have no way to see that. At least with the display, you can see the RPM change, so you know the encoder is good, for example. 

I doubt you damaged the display board too badly. If you can post some pics of the setup I might be able to see something to investigate further. If you don't have a backup display board, it might be a good idea to get one. Those are cheap at least. If you don't have the experience soldering, I could probably mod one of mine for you. Desoldering headers is a pain. Do try with a test setup though. Even just jumper wires breadboard style is fine if they are short.


----------



## luxige

ttabbal said:


> It looks like the installer defaults to C:\ti\tutorial.
> 
> There is some documentation here that might be helpful getting things going.  http://www.ti.com/lit/an/spra766/spra766.pdf?ts=1590694503172
> 
> I wouldn't think that damaging the solder pads would mess up the ability to run the encoder and servo. Though it's hard to debug issues with those without the screen. You might be able to run connected to the debugger and use breakpoints to see the changes in the encoder. The trick here is that a single wire mixed up can make it not respond, but you have no way to see that. At least with the display, you can see the RPM change, so you know the encoder is good, for example.
> 
> I doubt you damaged the display board too badly. If you can post some pics of the setup I might be able to see something to investigate further. If you don't have a backup display board, it might be a good idea to get one. Those are cheap at least. If you don't have the experience soldering, I could probably mod one of mine for you. Desoldering headers is a pain. Do try with a test setup though. Even just jumper wires breadboard style is fine if they are short.



Thank you, Travis!
A new display board is on the way. I'll connect to the stock pins at first to eliminate that variable.
I don't think I'll need to take you up on your generous offer of a board, but thanks very much.

The article you linked to looks interesting, though most of it is over my head. I think I could stumble through the tutorial if I had it, but it's not in my install. C:\ti only contains one folder, \ccs1000, which only contains \ccs and \xdctools_3_61_00_16_core.
One thing I failed to mention before is that this is v10 of CCS, the only version I saw on the TI wesite. That may be why I had to update the XDS110 firmware to get the code to flash.

I'll report back when I recheck all the cables, etc. Might be a day or two, I need a break!


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## ttabbal

Good luck! Sometimes taking a break is the best way to clear your mind. I've even thought up solutions while away from the computer.


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## GunsOfNavarone

I tried to read this whole thread...but its huge. It started to touch on this, but no real answer.
If I were to build something CNC...leadscrew, X axis, whatever....and I built the system off Arduino, would this work with Fusion360 or Mach 3? Does it work with the G code the design software generates? Or do I need to work with an entirely different controller? Can some short and dirty explain the controlling aspect of a CNC device? I'm very close to just buying enough to do one unit to see how much work it would be to covert my mill or (more likely) my lathe.


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## ttabbal

Gcode is pretty simple, it really amounts to move X 10mm type stuff. What the electronic leadscrew tries to do is a bit different. It's to sync the spindle with carriage movement at a fixed rate. That's why we can thread with it. I suspect you would need similar control for CNC conversion, but that's not what we're looking for with this. What we are doing is replacing the gearbox or change gears with electronic versions. 

Mach and linuxcnc seem to be the brain box, no need for microcontrollers. Though it might be useful for reading the encoder, for example. But the computer directly controls the motion system. These take the gcode and generate the pulses to move the motors around. 

Fusion360 generates gcode using the CAM module. It's a step above the motion system. It's a different type of software.


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## GunsOfNavarone

@ttabbal I wanted to avoid the ELS as there is more involved...timing one type of motion with another. What I need (or at least, really WANT to understand) is design software creates G-code, what does that go to, then what does that go to, and so on. It SEEMS like, depending how you want to do this, the hardware can vary.
I'd like to know WHAT I'm shopping for and why.


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## ttabbal

The easiest way to get a handle on that is probably to watch some YouTube videos showing really basic start to finish CNC stuff. It doesn't matter what kind of CNC. The basic process is the same, though the details vary.. 

You start with design software like Fusion360. Make a thing. It can be simple, think a wood coaster. Circle, extrude. Then you switch to the CAM process, take the thing and stock, determine zero points, and it figures out the movements. The output from all that is gcode. 

Feed that gcode to the motion control system. And set the machine zero to the same spot as in the design. People usually use the top of the stock in a corner or the center. Much like setting your zero when machining. There are fancy probes and such. Can be helpful, but not required. 

Hit go and hope you didn't mess up.


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## GunsOfNavarone

Ok, well this is what I think I'm looking at...the kind of direction I'm looking for.
Arduino UNO or clone (board)
G-shield (board)
DC power supply
Stepper motor (one for each axis) Nema 34?
4 wire (14 or 16 gauge?)

GRBL software download and install on Arduino board
G code sender (software for PC) 
In theory, I think this is a working model...g-code to g code sender to Arduino to steppers.


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## jaek

@GunsOfNavarone You got it. You need something to interpret the G-code into motion commands for each axis, and that's GRBL. Then you need something to use those motion commands to drive the steppers for each axis, which I guess is the G-shield and the power supply. Then you need the actual steppers (depends on the machine).

You might want to look at the Centroid Acorn - it looks pretty CNC friendly.


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## GunsOfNavarone

@jaek  OMG! that is EXACTLY what I'm in need of THANK YOU!


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## RJSakowski

GunsOfNavarone said:


> @ttabbal I wanted to avoid the ELS as there is more involved...timing one type of motion with another. What I need (or at least, really WANT to understand) is design software creates G-code, what does that go to, then what does that go to, and so on. It SEEMS like, depending how you want to do this, the hardware can vary.
> I'd like to know WHAT I'm shopping for and why.


Disclaimer: I'm no expert on g code but here goes

The function of CNC is to move the three axes of a machine in a coordinated fashion such that the path follows a defined pattern.  In addition to coordinating the position, the rate of travel of each of the axes is controlled.  A simple example would be to make a diagonal cut .05" deep from the origin to a point 1" to the right and 1" to the front, i.e. a 45º angle.  The spindle would be turned on at a specified speed, say 1000 rpm by the command S1000 M3 and the cutter would be lowered to the .05" depth at 10"/min. feed rate with the command G01 F10 Z-.05.  Next the command X1 Y1 F 20 will move the cutter to the coordinate1,1 at 20"/min., cutting the diagonal line.  It isn't necessary to resubmit the G01 command as it remains in effect until it is overridden with another command such as G00, G02, or G03.  G00 is called a rapid and moves at a maximum rate.  G02 and G03 move form point A to point B in arcs rather than in a straight line.

G code is a standardized command language which is then sent to a controller which translates the code into a series of commands for the individual stepper or servo motors in terms of stepper rate and direction and number of steps.  In addition the controller synchronizes the movement of the thre axes.  The controller can be one of many, Mach, LinuxCNC, and PathPilot being common for hobbyists.  The aforementioned controllers use a PC as the computer engine.  CNC controllers can be written for Arduino, Raspberry Pi, or similar microcontrollers as well. 

In the case of the ELS, then motion is rather simplified.  Only two axes are being used, the z axis and the spindle.  The primary difference is that the spindle motion is an independent variable which controls the motion of the z  axis as opposed to a CNC machine where all axes are dependent on the control program.  Note that a CNC lathe has feedback coming from an encoder which controls the  x and z axis, permuting the necessary synchronization required to successfully cut threads.

It is possible to write complete machining programs manually and for many years that is what was done.  However, when machining complex curves in two or three dimensions, this process is tedious and error prone.  This is where CAM comes in.  Software like Fusion 360 contains a sophisticated mathematics engine that is able to analyzes a three dimensional model and , with some guidance from the operator, create an effective g code program to create the three dimensional part.  

One g code program that I had contained over 200,000 lines of code. (https://www.hobby-machinist.com/thr...in-your-shop-today.14637/page-115#post-298744 post#3444)


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## GunsOfNavarone

Thanks @RJSakowski  I actually run CNC machines all day long, but I want to build a working single controller on my kitchen table. I am slowly now learning what that would take. This is why I said forget X,Y,Z.... I just want to be able to have a laptop on the table, send a command to turn the motor and watch a stepper move. I assume then, I would have a working axis nearly ready to go. I don't fully understand all the hardware needed to accomplish this (servos?) and, depending if I use an ACORN board or an ARDUINO...what will it take to get my PC to get the G code to the stepper. I've been reading a lot, but that is no replacement for someone here that has actually gone from start to finish with it.
On the ELS, I don't know that I would be able to give up manual use of my lathe, If you went this route and removed gearbox, could you still use it manually? I know you can add stepper to ELS rather than remove the gear box, seems like getting rid of that would be a win as long as manual us is unaffected. I know Clough42 has a video on this, I'll have to watch, he was the basis for my VFD mod on my G0602.


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## RJSakowski

GunsOfNavarone said:


> Thanks @RJSakowski  I actually run CNC machines all day long, but I want to build a working single controller on my kitchen table. I am slowly now learning what that would take. This is why I said forget X,Y,Z.... I just want to be able to have a laptop on the table, send a command to turn the motor and watch a stepper move. I assume then, I would have a working axis nearly ready to go. I don't fully understand all the hardware needed to accomplish this (servos?) and, depending if I use an ACORN board or an ARDUINO...what will it take to get my PC to get the G code to the stepper. I've been reading a lot, but that is no replacement for someone here that has actually gone from start to finish with it.
> On the ELS, I don't know that I would be able to give up manual use of my lathe, If you went this route and removed gearbox, could you still use it manually? I know you can add stepper to ELS rather than remove the gear box, seems like getting rid of that would be a win as long as manual us is unaffected. I know Clough42 has a video on this, I'll have to watch, he was the basis for my VFD mod on my G0602.


I'm sorry for overstating the obvious to you.  It is difficult to know what a person's knowledge level is.  I cherish my ability to run the lathe manually as well which us why I didn't consider converting to CNC.  I must confess, that should a need for a CNC lathe arise, I can revert to using my Tormach as a vertical CNC lathe.  The ELS doesn't preclude using your lathe manually.  You still control carriage movement with the half nuts.  You will engage the half nuts for power feed but this is no different than the OEM setup in principle with the exception that it is more convenient.

On the subject of an ELS, I believe the issue is how to synchronize the X and Z axis movements to the spindle orientation.  Clough does this by tracking the spindle position from the start of the operation with the rotary encoder and some heavy math computation but it seems to me that this is unnecessarily complicated  What is necessary is that, at a particular spindle orientation, the carriage will be at one of a number of points defined by the thread pitch.  I envision this as operating something like the thread dial,  

In threading, an initial carriage start and end position would be set by the operator as well as a spindle orientation.  The correct ratio of encoder pulses to stepper pulses would also be set.  To start the threading pass, the stepper driver to would be enabled and the spindle encoder would trigger the stepper driver to begin spending step pulses.  At the end of the run, stepper pulses would stop and the threading tool backed out.  After a pause which could be automatically set or ended by an operator carriage would be returned to the starting point and stopped.  The operator would make necessary cutter adjustment and arm the stepper driver for another pass and the process would repeat.

Since there is no need to keep track of total encoder counts. the spindle wouldn't need to be reversed which is a plus for lathes with thread on chucks. Also, because the end point of the threading pass is precisely defined, threading to a shoulder is now practical.  Cutting left hand threads simply involves swapping the start and end points and changing the stepper motor direction.

Because spindle speed isn't precisely controlled, you would probably want to track it and make real time adjustments to the stepper rate to keep in sync.


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## GunsOfNavarone

And all that’s sounds terribly complicated. I don’t want to throw a lot of money and stress at something that I would have to ditch as it doesn’t work right. This is the attraction to a plug and play system, but the one or two I can find are not as appealing and quite pricey. I would be happy to share costs and elbow grease to anyone capable who wants to go down this path with me. It’s really not money concerns directly as much as it is wasted money... been there, done that.


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## RJSakowski

GunsOfNavarone said:


> And all that’s sounds terribly complicated. I don’t want to throw a lot of money and stress at something that I would have to ditch as it doesn’t work right. This is the attraction to a plug and play system, but the one or two I can find are not as appealing and quite pricey. I would be happy to share costs and elbow grease to anyone capable who wants to go down this path with me. It’s really not money concerns directly as much as it is wasted money... been there, done that.


Going down a new development path, you will still have the cost of a stepper/servo and driver, gear belts, and pulleys, and power supplies.  A less expensive encoder is possible but that wasn't a huge expense.  The remaining cost in the Clough ELS are Clough's board, the display, and the Launchpad which amounts to around $65.  My cost was a little over $200 in total , using an existing power supply and repurposing  an old mains load center.

 My suggestion above was based largely on what I saw as an unnecessarily complicated scheme requiring additional computing horsepower.  On the whole, I am happy with the performance of the Clough ELS.  What I see as shortcomings are the lack of ability to dial in a user defined feed rate and not being able to effectively use the enable feature of the driver.  To a large extent, this is due to a limitation in the display board.  With a little creative programming, this could probably be worked around.  

The German Rocketronics ELS looks like a very nice unit  and actually closer to a true CNC in function but is lacking the ability for the user to enter in custom programs, relying on preprogrammed routines.  Adding the x axis stepper drive, one is almost at a fully functional CNC lathe.  At that point, I would be inclined to go full CNC.


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## ttabbal

The thing I like about the Clough42 system is that it is relatively simple. It tracks the spindle and moves the leadscrew to match. It is an electronic gearbox and doesn't try to be much more. You can add some things, but if you go much further you get into CNC land. This is a a manual machine that I don't have to fuss with change gears on. I didn't mind so much for threading, but I was already thinking of adding a variable speed drive for feed rates. He beat me to it and included threading in the mix. 

I would like to see custom speeds and such, as well as using the power button to disable the driver. There is a patch out there for that, I just haven't taken the time to integrate it. Right now I go old school and flip the switch on a surge protector strip.


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## GunsOfNavarone

ttabbal said:


> The thing I like about the Clough42 system is that it is relatively simple. It tracks the spindle and moves the leadscrew to match. It is an electronic gearbox and doesn't try to be much more. You can add some things, but if you go much further you get into CNC land. This is a a manual machine that I don't have to fuss with change gears on. I didn't mind so much for threading, but I was already thinking of adding a variable speed drive for feed rates. He beat me to it and included threading in the mix.
> 
> I would like to see custom speeds and such, as well as using the power button to disable the driver. There is a patch out there for that, I just haven't taken the time to integrate it. Right now I go old school and flip the switch on a surge protector strip.


So if I understand @ttabbal you HAVE clough42's ELS? Can I hit you up for help? I ordered his board today, but looking through the 3 pages of many files....I have no idea WTH to do with them.


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## RJSakowski

GunsOfNavarone said:


> So if I understand @ttabbal you HAVE clough42's ELS? Can I hit you up for help? I ordered his board today, but looking through the 3 pages of many files....I have no idea WTH to do with them.


I also have Clough42's ELS.  Glad to help as well.


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## ttabbal

GunsOfNavarone said:


> So if I understand @ttabbal you HAVE clough42's ELS? Can I hit you up for help? I ordered his board today, but looking through the 3 pages of many files....I have no idea WTH to do with them.



Yup. I built one. A few of us here have. 

The files are the code for the launchpad board. He has a step by step video showing how to set up the build tool and load the code into the board. It looks complex, but it's not too bad overall. If you get stuck at a spot, I'm sure one of us can get you going. My build is documented on the forum here.. 









						Electronic Lead Screw
					

I'm going to attempt to adapt clough42's ELS to my PM1127. I figure I might as well do it publicly in case it ends up being useful for someone else. I have most of the parts now, and have the electronics and servo running on the bench. The first thing I decided to mess with is the rotary...




					www.hobby-machinist.com


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## GunsOfNavarone

Thank you @RJSakowski  and @ttabbal I know I'll get stuck more than once. What parts did you have to machine vs what did clough42 make available on his website? What about the box/control buttons he has in his video? As far as bypassing the ELS, could you build a power switch into the unit somewhere?


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## RJSakowski

I machined the motor mount and the encoder mount.  My motor is a NEMA 24 hybrid stepper and with a little work, it fit under the headstock.  The encoder is mounted forward from the spindle and slightly above.  Some details of the build are in post # 233 in this thread.

My display box has separate power switching for the ELS Launchpad and the stepper driver so I can switch off the stepper and still leave the ELS display active.  I made my own SolidWorks model and machined the cover plate to fit an existing box.  Not having a 3D printer, I made Delrin push button extensions.  I also installed new LED's with longer leads so the came up through the cover plate.I also engraved the lettering on my box with my CNC.  Clough is offering face plates made from printed circuit board soon.


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## greenail

GunsOfNavarone said:


> What I need (or at least, really WANT to understand) is design software creates G-code, what does that go to, then what does that go to, and so on. It SEEMS like, depending how you want to do this, the hardware can vary.
> I'd like to know WHAT I'm shopping for and why.



Here's the thing, not all arduino type CNC platforms support threading cycles or constant surface speed.  You want to check that the platforms supports G96 and G76.  Threading is not as simple as simple gcode motions and the motion planner needs to be able to do some sort of synchronization for the spindle position.  As far as I know there are forks of grbl that support threading but they are all fairly fringe and not super well tested.  There are a couple grbl mega forks that supports it as well as grblHAL ( only  MSP432  supported for spindle sync).  There may be others but it seems CNC lathe is much less popular than mill type CNC.

Regarding Centroid Acorn, expect to pay an extra $140 for the CNC 12 lathe pro software.  This is tied to the hardware so you can't use it for more than one machine.  Also expect to spend ~100 on a differential signal encoder which is required by the hardware.  you may be able to pickup a used one on ebay.

Finally, Clough's system still requires a ton of manual effort.  You will be cranking handles quite a lot without the X motion.  If you add a motor to your X you are 90% of the way towards full CNC hardware setup.  All you need to add is end stops.  That is not to say you will have a machine which will work well for CNC lathe work.  The backlash is typically so bad on a small lathe you may have a hard time with it.

If you still want to look at the arduino path take a look at this thread where some very simple encoders are hand made and the folks are working out the kinks for threading:  https://github.com/gnea/grbl-Mega/issues/26.  

The nice thing about the arduino/grbl mega path is that you can do it very cheap.  You can pick up a mega for $6-10, stepper drivers are ~$7 each, $30 for a decent power supply, $12 for a 2400 CPR encoder.  3NM motors are ~$70 for 2.   So for around $120 you have a fun project to fool with.  The Centroid Acorn would run you $650 to start assuming you used the same motors/drivers.   The Acorn will work out of the box but I would highly recommend you read the manual before you pulled the trigger.  I find their software very clunky.


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## kb58

Don't forget the gears and belts; I bought US-made parts and it was around $100 as I recall.


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## GunsOfNavarone

I am going to just copy to the finest detail, Clough42's ELS as @ttabbal  and @RJSakowski did. Sounds like it was fairly straight forward and works well.
The money aspect has no bearing to me...within reason. Looks like its sub $500, I get that for allowance jst for taking out the trash and mowing the yard.


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## luxige

ttabbal said:


> Good luck! Sometimes taking a break is the best way to clear your mind. I've even thought up solutions while away from the computer.




I hope you guys weren't thinking I was ignoring your input, I just had to walk away from this for a while. I was thiiiis close to dragging the project out to a remote field and giving the whole mess an Office Space-style geek beatdown. Also, waiting on a new display board, which arrived today.

I opened an issue on Github and a couple guys suggested maybe S9 was in the wrong position. I was aware of the S9 default position. Knowing the meaning of the word "default," I simply left it alone, never even touched the tape. Maybe TI doesn't know what a default is; they were right, the switch was in CAN bus position. So, now the encoder is driving the servo!

Unfortunately, the display is still out other than the small LED to the left of the digits. That light had been intermittent, which I traced to a short between the CLK and GND pins in one of my connectors. That's fixed now so the LED is on steady, but that's it. I checked continuity from the display board header pins all the way to the first components on the booster board (C5, C4, C3, C6, and +5v). The first display and the replacement respond the same, or rather they don't.

Next? New booster board?


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## GunsOfNavarone

Wow @luxige  even though I have already ordered 4 or 5 parts for this mod....your remarks are the thing that puts the fear of God in me....and I didn't even understand half of what you said. In the end, would you do if you had the chance to go back? No harm no foul, 0 dollars spent?


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## Dabbler

I've been closely following this thread and Clough42's videos.  I think I am going to buy the Robotroniocs unit, even if it is expensive.  Plug and play looks good to me at this point.


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## luxige

GunsOfNavarone said:


> Wow @luxige  even though I have already ordered 4 or 5 parts for this mod....your remarks are the thing that puts the fear of God in me....and I didn't even understand half of what you said. In the end, would you do if you had the chance to go back? No harm no foul, 0 dollars spent?



If I can chase down this last gremlin and get it working, yeah I think it will be great. I have had some bad luck and I am very much a novice, so it's been a tougher road than it could have been.

I'm replacing the QCGB on an older 12x36 that I bought on a popular auction site. The gearbox is unbelievably trashed, so this project is a perfect fit. Will be?


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## GunsOfNavarone

In mechanics...I can fix or build anything. In electronics and particularly, code.... yeah. no.


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## GunsOfNavarone

@Dabbler I looked at that unit. Being German (which I am and speak some) I suspect it will be difficult to get it up and running. Not that this build it yourself unit won't be, but that system seemed more intrusive? I don't know, but I wasn't feeling it.


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## Dabbler

@GunsOfNavarone all of the Rocketronics documentation and manuals are now also in very well written English.  I don't anticipate any problem with it at all.  I don't mind the menues in German, even if they eventually offer English for those too...


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## GunsOfNavarone

@Dabbler 
Das ist gut! I do wish James (clough42) had a plug and play, but I'm hoping with help here, I'll get through it.


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## dago

luxige said:


> Fiiiinally got all the parts in.
> There’s a new development that brings up a problem. Of course.
> 
> My initial plan was to mount the hybrid servo motor within the lathe bed, similar to Gus' idea (as posted in a Github issue), and drive the gearbox input with the servo via a M5 belt. This would let me put an idler on the change gear banjo and I'd have an easy way to adjust the belt tension by moving the idler up or down. But two things interfere. Most importantly, the QCGB is so badly damaged that I only have a couple of working ratios out of over a hundred possibilities. The simplest one is 32:15, gearbox input:leadscrew. I was worried that adding those factors to the numerator and denominator calcs might be too much. (James had advised Gus against using his 120 and 127-tooth change gears between servo and leadscrew, because the math might be too much heavy lifting for the microcontroller).   Then I found that my initial measurements were wrong, and placing the motor inside the lathe bed would be extremely challenging, so it's all moot anyway.
> So I decided to add an extension to the tailstock end of the leadscrew and drive it from there. I gutted the gearbox, leaving only the gears which connect the leadscrew and feed shaft. They run 1:1.
> Here's the problem - the feed shaft is geared within the carriage apron to a ratio of (approximately) 19 turns per inch of carriage travel. So the leadscrew and feed shaft produce different rates of carriage movement when turned at any given stepper value. I don't want to abandon the feed shaft and do feeds with the 4TPI Acme screw, so I'm trying to figure out the best way to use both. I have a few ideas.
> Solution 1: Alter the Feed formula by 19/4ths. Actually, I'd just round it off to a factor of 5 in the numerator, that's only a 5% error in feed rate.
> Solution 2: Define a new variable (say, "feedshaftrate") to replace the leadscrew TPI variable in the Feed formula. Set the new variable to 19 TPI and I'm done. However, I have Zero coding experience, so I'm not sure I'm up to it.
> Solution 3: Change the Feed tables, so the the value displayed on the LED panel is low by a factor of 5. So for example, selecting .010"/rev (as displayed) would actually be telling the controller to feed at .050"/rev, but the slower feed shaft rate would actually result in a feed of .0105. Close enough. I'd have to add some rows to the table at the top end to get the faster speeds, and delete the slowest speeds. Again, Absolute Zero coding experience.
> Okay, what would you do? Am I missing an easier answer? Any input will be appreciated, so thanks in advance.




I also had this same problem  you have i think, Clough use lead screw for thread and feed.
I have different ratio on lead screw and feed bar. Simple way i found to solve this is a simple code modification.
In Table.cpp, line 86 you should have this

#define THOU_IN_DENOMINATOR(thou) ((Uint32)ENCODER_RESOLUTION*1000)

I changed to this 

#define THOU_IN_DENOMINATOR(thou) ((Uint32)ENCODER_RESOLUTION*180)

I change only the multiplicator by trial and error and with this simple mod i was able to  correct the feed rate.

This only change the feed rate ratio and do not change anything for threading.


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## ttabbal

@luxige Looks like you're heading the right direction now! For the display, the length of the cable and exactly how it is wired matters. Start simple with 6" individual wires. That's almost guaranteed to work. A longer run with multi conductor cable can go sideways easier than you think. You start getting into stray capacitance and crosstalk. I can explain how to fix it, but I want to make sure you have good parts first. I'm 90% sure you do. 

@dago Check my version of the code. I made it so you have a simple setting in the configuration file with everything else to set a different feed rate. 

No harm doing the plug and play. But seriously, if you can troubleshoot an engine and make a part from a print, you can handle this. I came the other direction, it's easier than it looks. You just have to break the problem down till you figure out where the issue is.


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## luxige

dago said:


> I also had this same problem  you have i think, Clough use lead screw for thread and feed.
> I have different ratio on lead screw and feed bar. Simple way i found to solve this is a simple code modification.
> In Table.cpp, line 86 you should have this
> 
> #define THOU_IN_DENOMINATOR(thou) ((Uint32)ENCODER_RESOLUTION*1000)
> 
> I changed to this
> 
> #define THOU_IN_DENOMINATOR(thou) ((Uint32)ENCODER_RESOLUTION*180)
> 
> I change only the multiplicator by trial and error and with this simple mod i was able to  correct the feed rate.
> 
> This only change the feed rate ratio and do not change anything for threading.



Thanks, that's pretty close to what I have done. If you want to have metric feeds also, it's a little more complicated. Ttabbal posted some code changes on the Gthub page as a Pull Request. It adds a new formula for mm feeds, and a new display table.


----------



## luxige

ttabbal said:


> @luxige Looks like you're heading the right direction now! For the display, the length of the cable and exactly how it is wired matters. Start simple with 6" individual wires. That's almost guaranteed to work. A longer run with multi conductor cable can go sideways easier than you think. You start getting into stray capacitance and crosstalk. I can explain how to fix it, but I want to make sure you have good parts first. I'm 90% sure you do.
> 
> @dago Check my version of the code. I made it so you have a simple setting in the configuration file with everything else to set a different feed rate.
> 
> No harm doing the plug and play. But seriously, if you can troubleshoot an engine and make a part from a print, you can handle this. I came the other direction, it's easier than it looks. You just have to break the problem down till you figure out where the issue is.



Thanks, Travis! You guys are helping to put my mind at ease. That said…

I made up a very short bit of ribbon cable, probably not even 3" and it's still no dice.
I also checked the gpio connectors on the booster, all 40 pins, for good solder joints and no shorts.
Still dead except for the LED, which I guess is a power indicator. (?)
The digits and the eight status LEDs have never so much as flickered.

The code is still driving the servo with encoder input. Correctly? Well, who knows.

What's next?


----------



## GunsOfNavarone

What caused your LED display to go south? Is there any chance the same issue damaged something else as well? I hate those INVISIBLE gremlins.


----------



## kb58

luxige said:


> Thanks, Travis! You guys are helping to put my mind at ease. That said…
> 
> I made up a very short bit of ribbon cable, probably not even 3" and it's still no dice.
> I also checked the gpio connectors on the booster, all 40 pins, for good solder joints and no shorts.
> Still dead except for the LED, which I guess is a power indicator. (?)
> The digits and the eight status LEDs have never so much as flickered.
> 
> The code is still driving the servo with encoder input. Correctly? Well, who knows.
> 
> What's next?


Buy another display board, they're really cheap.


----------



## luxige

kb58 said:


> Buy another display board, they're really cheap.



I did, neither board works. I tried the new one using the stock, top-mounted header to eliminate the possibility of a bad solder job on the first one.
Both boards have shown no sign of life from either the digital array or the status LEDs.
It seems like the problem is somewhere else and I don't think it's the cable.
I've thoroughly checked the cable for continuity, and replaced it with a short test cable to eliminate interference.
More info in post #379.


----------



## ttabbal

luxige said:


> Thanks, Travis! You guys are helping to put my mind at ease. That said…
> 
> I made up a very short bit of ribbon cable, probably not even 3" and it's still no dice.
> I also checked the gpio connectors on the booster, all 40 pins, for good solder joints and no shorts.
> Still dead except for the LED, which I guess is a power indicator. (?)
> The digits and the eight status LEDs have never so much as flickered.
> 
> The code is still driving the servo with encoder input. Correctly? Well, who knows.
> 
> What's next?




Well, that sucks.  

My guess is something is off in the PCB from Clough. That one will be difficult to diagnose if you don't have an oscilloscope or logic analyzer though. You're 100% positive you don't have a pin swapped on the cable? It's easy to do, been there, done that. You can get decent little USB LAs on ebay for <$20. Well worth having around if you are going to mess with electronics. 

I think the LED you are seeing is for power. So power/GND are probably good. If you have an arduino board around, you could try testing your display board with one of those.. https://blog.3d-logic.com/2015/01/10/using-a-tm1638-based-board-with-arduino/  I think it's unlikely you got two bad display boards.


----------



## luxige

ttabbal said:


> Well, that sucks.
> 
> My guess is something is off in the PCB from Clough. That one will be difficult to diagnose if you don't have an oscilloscope or logic analyzer though. You're 100% positive you don't have a pin swapped on the cable? It's easy to do, been there, done that. You can get decent little USB LAs on ebay for <$20. Well worth having around if you are going to mess with electronics.
> 
> I think the LED you are seeing is for power. So power/GND are probably good. If you have an arduino board around, you could try testing your display board with one of those.. https://blog.3d-logic.com/2015/01/10/using-a-tm1638-based-board-with-arduino/  I think it's unlikely you got two bad display boards.



I heartily agree with your first and last statements!

I'm pretty sure about the cable. I hooked it up and checked continuity between header pins on the display board and booster. CLK to CLK, etc. Also, I would have to have screwed up the short test cable too.

I'll order a new booster board. Cautiously optimistic…


----------



## kb58

Well, you have a HUGE advantage: it's already a proven design that's known to work. For that reason, the problem comes down to: bad hardware, a failed sw load, and/or a defective cable. It's just a matter of compartmentalizing the issue. I don't recall now, but does Clough42's sw light or blink any LEDs on the main board? That goes a long way toward knowing that the main code is running.


----------



## ttabbal

The servo is reacting to the encoder, so I think the software is good. It wouldn't hurt to try reflashing, can't hurt. I wonder if the booster board had a transistor go bad or something..


----------



## kb58

Ah, okay, that's good to hear. So that limits the problem to the control-to-booster board cable, the booster board, booster-to-display cable, or the display. Since you swapped in a second display and that didn't fix it, it's probably not that. You checked the booster-to-display cable, so that's probably not it, leaving the booster board or control-to-booster board cable. Do a pin-to-pin check of that cable.

I'd look over his booster board with a magnifier, as it's really easy to miss a surface-mount connection problem during assembly.

One trick I use when trying to trace down problems is to physically push on the suspect board with everything powered up. This very slightly flexes it, and usually identifies any intermittent problem. Same goes for connectors; with it powered up, give them a slight wriggle.

Oh... do the buttons do anything?

A shame that you don't have a scope, but then we wouldn't be here!


----------



## RJSakowski

luxige said:


> Thanks, Travis! You guys are helping to put my mind at ease. That said…
> 
> I made up a very short bit of ribbon cable, probably not even 3" and it's still no dice.
> I also checked the gpio connectors on the booster, all 40 pins, for good solder joints and no shorts.
> Still dead except for the LED, which I guess is a power indicator. (?)
> The digits and the eight status LEDs have never so much as flickered.
> 
> The code is still driving the servo with encoder input. Correctly? Well, who knows.
> 
> What's next?


If the servo is tracking the encoder, you can do a rough check of the software flash.  The power on state is forward, feed, inch and the rate is .005".  Depending on your lead screw pitch and if all the parameters are set correctly, you should be able to rotate the spindle manually and count the turns of the spindle for one complete revolution of the lead screw.  In my case, I have a 12 tpi lead screw  for a pitch of .083333.  One revolution of the lead screw will require 16.6667 spindle revolutions.  An 8 tpi lead screw should require 25 spindle revolutions for one lead screw revolution.

If this is happening, I would guess the the flash was good.  

I noticed that your Clough board has a green power on led whereas mine has a red led.  My board came from his second build.  Hopefully, there were no other changes besides the led color but who knows?


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## RJSakowski

Good point about the buttons.  Although the display leds aren't lighting, the switches may be functioning.

From the power up state, five pushes of the up button will double the lead screw rpm and 11 pushes will quadruple it.  From the power up state, push the feed/thread button once and the down button 11 times to give you 8 tpi which will be 1:1 spindle/lead screw for an 8 tpi lead screw.


----------



## luxige

The Eagle has landed!
And I'm very grateful for the guidance and support from you folks.

I had already broken down the bench test setup to await a new booster from James. Then kb58's question about indicator lights on the boards made me look again at the photo I posted of the main board under power. Sure enough, LED1 is not on in that photo, and it is on in James' videos. I set it all up again for some more pictures. In doing so, I saw the problem - when I was setting S9, I didn't move it all the way, it was kinda in the middle.

I checked a thread pitch and a feed rate, in both inches and mm, and it seems to be spot on.
And there was much rejoicing...

Thank you again!


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## RJSakowski

Glad you got it sorted.  Far too often, it's the little things that trip us up.


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## ttabbal

Always the things you thought you had nailed down! Glad you have it running, always nice to see a problem get fixed.


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## GunsOfNavarone

Ok folks that have working Clough ELS, I have my servo/stepper, driver, numeric display and Clough boost board. I think I am ready to start building, just need some cables (not sure what types of cables?) and a encoder. I think he has some simple instructions on github..I have cloned the whole think on my laptop. Any initial suggestions on the earliest part of the assembly? I am straight up DUMB when it comes to building these sort of things. The VFD was more so just wiring/electrical...this is FAR different. 
Does anyone have have the ability to router the breakout box lid for me?  I don't know if/when Clough will make those available, getting him to answer any questions is like pulling teeth!


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## RJSakowski

GunsOfNavarone said:


> Ok folks that have working Clough ELS, I have my servo/stepper, driver, numeric display and Clough boost board. I think I am ready to start building, just need some cables (not sure what types of cables?) and a encoder. I think he has some simple instructions on github..I have cloned the whole think on my laptop. Any initial suggestions on the earliest part of the assembly? I am straight up DUMB when it comes to building these sort of things. The VFD was more so just wiring/electrical...this is FAR different.
> Does anyone have have the ability to router the breakout box lid for me?  I don't know if/when Clough will make those available, getting him to answer any questions is like pulling teeth!


I bought the suggested encoder on eBay and the Launchpad from DigiKey.   For cables, I scrounged my mine from salvaged wiring over the years.  Nothing special other than the required number of conductors.  The encoder comes with an appropriate cable.  As to the connectors, you will need one for the encoder cable and a pair for the display cable; 5 position by .1" centers.  My 5 volt power connector came from a wall wart.  All the connectors are available from DigiKey, Mouser, or Jameco as well as on eBay. I didn't bother with panel mount connectors as all the connections on my setup are easily broken internally.

As to the cover plate for the box, if you look at post #233 on this thread, you will see my solution to the cover plate.  This version can easily be done by hand with the exception of the labels.  I used a spare box at hand so the dimensions don't match the box the Clough used.


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## GunsOfNavarone

Thanks RJ. I am unsure of what cables you're cable you are referring to, I'll just have to wait until I have everything and see if I can figure it out. I will try to search for a "5 position by 1" center" cable.but I'm guessing that will mean more when Istart putting this all together. The Texas Instruments Launch Pad board will be here today. I'll look at post #233, but I'll tell yeah, I really dig how his turned out, If I cant do that, I'd really like to figure out how to do a LCD screen, but as of right now, that seems like magic as to how that even would work.


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## GunsOfNavarone

@RJSakowski Yeah I saw post #233, that's perfect, but again, I have no CNC router, I guess I could buy one of those small/cheap Chinese routers, but I suspect it would take sometime to figure out how to use it and God knows if it will _really _engrave Aluminum.....


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## RJSakowski

The encoder comes with a cable.  You will need a cable from Clough's board to the display board, from the Launchpad to the driver, and from the driver to the main power supply,   The dimensions refer to the connectors for those wires.  Here is an example: https://www.jameco.com/z/22-01-2057...ptacle-5-Position-2-54mm-Straight_234739.html 

As to the control board, I stuck with Clough's design.  I'm not at a point where I want to start exploring alternative I/O devices as it would necessarily mean rewriting Clough's code.

As to DIY engraving, there are other potential solutions.  The photoetching process used for printed circuit boards could be adapted easily for aluminum or you could simply mimic Clough's solution, buying photosensitive pc board and making a photomask  and exposing to uv light (sunlight). The mask artwork could easily be laid up in one of many CAD applications and printed out on a transparency to expose the board.   A while back, I did an etching process on my 1-2-3 blocks using a swab dipped in a table salt solution and a battery.


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## RJSakowski

The need to do your own engraving is a great excuse for another tool.


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## ttabbal

For the wires, I used cat5 network cable. I have a bunch of it around. I also used the round aviation style connectors he used. For the connection to the display/control board, if you go that way, connect all of the stripe wires together to ground and use the solid ones for signals. It helps with noise. I got it wrong the first time and had issues.


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## GunsOfNavarone

@ttabbal thanks, that’s the kind of headache stuff I really appreciate to know out the gate!


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## GunsOfNavarone

So I soldered up the boards, uploaded the software/flashed the Launchpad and success! Well, at least that part is up. I have Encoder, Hybrid Servo/stepper, pulleys and driver en route. I need to figure out a cable from Display to launch board, but that connects to some aviation connectors and I don't know who/what/where on that cable. I will need to order belts (I think one is 147/149 teeth the encoder one I have no idea). Where the heck I'm mounting the driver/launch board/power supply...I don't know. I already have a big electronics box on the wall from VFD, don't want another one. Gotta make mounting assembly for Encoder and servo. Where did you guys mount? I really want it "under the hood" if possible. I know Clough discussed it, but I don't know if that ever happened. Since the launch board it reading "clough" at startup, it really should be a situation of hooking everything up now as we have the same lathe/encoder/servo/driver, therefore same settings in the code.


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## ttabbal

You can see pics of how I mounted things in my thread. The encoder is on a little adapter replacing the gear sets. The servo is on a bracket mounted to the headstock case. I ended up just cutting a hole in the cover to stick the motor through. I would have liked to mount it in a way to avoid that, but didn't find a good spot on my lathe. I know some lathes have spaces you can fit the motor, so it just depends on you machine. 

I used network cable and the aviation connectors, just solder the wires into the right spots. 

Clough has a video about building the enclosure box. I did something similar for mine.


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## GunsOfNavarone

I went to his thingsverse page....there are only 2 files, one is lid.stl which when I open are just the cut outs...the other is lid.step file which none of my software recognizes so I have no idea whats in it. Being I have no CNC I guess it isn't of value anyway. Looking at a $2000 StepCraft router just for this purpose, hopefully I can find the file before I get the CNC. Would you happen to know if it was an STL file or STEP file? I really don't know the diff at this point. I think I will try to mount stepper just above motor as he SAID he was going to try to do, I'll have to check to see if he updated...


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## ttabbal

I know there was more than that there before... 









						Lathe Electronic Leadscrew by clough42
					

I am developing an electronic leadscrew for my lathe, which is a device that replaces the change gears with an electronic controller and a motor.  This project is a repository of the brackets, pulleys, control panel parts and reference models used in the prototypes and final design. See the...




					www.thingiverse.com
				




It shows 32 files... 

To answer about the formats, STL is a mesh object usually used for 3D printers. STEP is a CAD format, more for making changes to the design. 

When I made the control box, I used the STEP, imported into Fusion360, and added the lettering and such. The lids are not particularly flat, so they ended up a little off, the depth of the lettering is not consistent. People have made them by 3d printing the lid, cnc, and things like the PCB method. I'm not sure if he released the layout files for the PCB. 

Another option might be to use laser cut acrylic for the lid. Or using one with marking spray on the aluminum.


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## kb58

James Clough has just posted a new Youtube video announcing the availability of his controller panel -


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## davidcarmichael

GreatOldOne said:


> He’s up to video 6, where he’s been doing test cuts with the prototype.


The button board and display panel just sold out (100) on Ebay.


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## RJSakowski

Pretty amazing.  15 minutes to sell 100 boards. It speaks to the popularity of this project.


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## Winegrower

I am anxious to be the 1000'th installation on a Takisawa lathe.     I am not really an early adopter, I suppose.


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## jlesser27

Dang, I missed it hopefully he will produce more. 


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## kb58

Took roughly an hr to sell out, but in the video he said he'd make more.


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## jlesser27

My encoder showed up today just waiting for 3 more pulleys. Haven’t been this excited for a build in a long time. 


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## ian999

I am deep into the process of putting a Clough42 ELS on my 1949 Myford ML7.

I am also looking for any help/guidance/juju that will make this thing work, else I will send it to the scrapheap in the sky and buy a Rocketronics outfit.

I am following exactly the process laid out by Clough42. I have a TI F280049C with a Clough42 booster board. I have an Omron E6B2-CWZ6C encoder and the hybrid servo motor specified by Clough42.

In putting this all together I treble checked continuity and crosstalk. I admit to being a klutz regarding soldering but all the connections are fine and work properly. I did manage to blow 2 of the Display boards (not connected to anything at the time) when I tried to desolder the 5-pin connector. I ended up with one of Clough42 display kits which look really nice -- if they worked.

Regarding the display, I found that I could solder the leads to the board as delivered, then bend the pins, suitably insulate everything and fit the whole thing into a slightly bigger box. No desoldering !!

The display lights up -- the opener with the Clough42 logo, then the ELS 1.1.02 version, then the left hand side shows 0, the right hand side works fine allowing me to set threads etc. The problem comes when I plug in the leads from the encoder into J12, the display dies just showing a live power LED. When connected, the 3.3v LED on the booster board turns off but the 5v remains lit.

OK says I, I must have screwed something up and blown a board. So I sequentially replaced the booster board and the encoder. No Go. Nothing changed so I bought a new TI board.

This sucker would not even boot no matter what I did. I tried CCS v9.0.1, v9.1.0, v10.1, v8.something -- nothing, and in between times I struggled with our friend Microsoft which released a new version of Win10, so I have gone through the issues of unsigned drivers. That is now behind me with signed drivers on Win10 v1903, but still the new board refuses to connect saying it cannot find XDS110.

Board settings are as I think Clough42 is now specifying -- S3 both at zero, S4 at 1, S9 at 1.

Does anybody have any ideas?

I think the whole concept is a great idea and will bring life to many old hunks of rusting lathes. Think about it, when you go looking for old lathes you often find the only things missing are the change gears, which are virtually impossible to replace. This project, if it worked, would fix that.

I should say that I am not *****ing about Clough42 as I think his videos are the very best on the web and he clearly makes an effort to do them well. In particular the sound management is very good and he enunciates his words well.

Does anybody have any ideas.

Thanks, Ian


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## RJSakowski

Welcome to the forum.  I just enough about the system to get into trouble but I'll give it a go. I built my ELS in January and am running version 1.0.03 of the firmware.  Offhand, if you got the display to light up and display the Clough42 and version  and you can run through the various threads and feeds, you were successful in flashing the Launchpad.  When you plug the encoder in and the display goes dark, it sounds like a short or wirng configuration.  It is also really easy to reverse the encoder plug.  If you remove the encoder and reboot the Launchpad and it comes up as before,chances are no damage was done.  If the display is now dark then it is likely that some damage was done.  

I don't have the boards in front of me but as I remember, the booster board supplies the voltage for the Launchpad, the display, and the encoder.  I wold begin by removing the booster board from the Launchpad and powering it up.  You should get the 5 v. and 3.5 v. led's to light.  I wold also check the actual voltage.  As I recall, you can access those voltages from just behind the power socket.

To go much deeper, I will have to dig into the circuitry as seven months is a long time ago for an old codger like me.  There are others on this forum who are much more knowledgeable than me and I'm sure we can get you some help.


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## RJSakowski

Ian, if you look through the previous posts on this thread, you will be able to identify those member who are more knowledgeable.  If you click on their handle to the left, it will open a new window where you can send them a private message.  You will find that members of this forum are generally willing to help others.  
Good luck


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## kb58

Agree with RJSakowski, you had it working. As he said, you're at least shorting the encoder inputs, or more likely shorting its power to ground. Agree that you need to power it all up again without the encoder to get yourself back to Square 1. If that means going back to the previous HW that you know works, do that. Then, very carefully check out the wiring to the encoder, as it's highly likely that you've miswired one or both ends of the cable/connector. If that doesn't turn up anything, put a volt meter on the voltage that powers the encoder before you plug it in, and see what it does when it is plugged in. My bet is that the voltage will go to zero, and that means that the cable is miswired, or that the encoder is defective (unlikely but remotely possible).


----------



## GunsOfNavarone

Yeah, seems straight forward. If you had it working then plugged the encoder in and it all went south, back up. Unplug the encoder, if everything working again? If yes, oh thank you sweet Jesus! You have the wiring wrong for encoder. I can easily pull mine and give you that as a double check.
If, when the encoder is unplugged, it's still a no go, you gotta figure out what's blown. I'd start with the booster board. It's cheaper/easier and deal with the voltage needs (which if you mis-wired the Encoder...I'd GUESS the culprit.


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## ian999

RJS, kb58, Guns,

Many thanks for responding and of course you are all correct.

I definitely had triple checked the continuity and lack of crosstalk in the encoder cable, but like an idiot I had plugged the power pins in the wrong way round!

The situation now is that the Control Panel lights up and reads zero for RPM, and the various settings for the right hand side of the panel all seem to be selectable. Firing up the lathe to rotate the encoder produces no change in the panel -- still zero.

Likewise there is no reaction at the stepper motor, but that is progress.

I should add that this is with Encoder #2, Booster Board #2, and TI Board #2 which I eventually got to boot and flash v1.1.02. I have been doing my best to support the US economy.

Thanks for your input and I am now going to rest for a while to figure out the next steps.

Ian


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## kb58

Probably blew up the encoder. Reversing polarity is worse than shorting the supply voltage to ground, because the power actively tries to feed through the device in the reverse direction, often succeeding.


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## GunsOfNavarone

Oh man Ian, I wish I could offer some better direction. (I looked online for a simple encoder test (to check if yours is bad) most I came across require an oscilloscope, I'm assuming you don't have. I't really SEEMS that your launch board is good, you led screen works so I assume it and the boost board are good. You have attached the encoder correctly? (its printed on the encoder and the launch board says next to each pin) Unless you have he stepper connected, I'm not sure you'll have any feedback to know if its worked (maybe RPS?) So next round of questions, are you sure the stepper is connect to power supply correctly? Also, there are a few connection for the stepper, the jumpers and the wires are a bit confusing..obviously the serial cable isn't an issue. You setup the launch board by setting the switches (those ity-bity ones) correctly?


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## RJSakowski

A bit of advice re: the encoder and display connectors.  Mark the ground pin on the Launchpad board and on the encoder  connector and the +5 pin on the boost board and the display connector with a Sharpie.  The visual aides are added insurance against reversing the connections.

Here is some information on the encoder.https:  //www.ia.omron.com/product/item/2453/
Looking at the pin assignment of the Lunchpad, I don't believe that the encoder would be damaged by reversing the plug.  It would put the supply voltage across two output pins (2A & 2B).  If the Launchpad port is damaged, you should be able to use J13 by changing the switches. https://github.com/clough42/electronic-leadscrew/blob/master/docs/images/LaunchPad.jpg


----------



## ian999

Regarding the Clough42 ELS on a ML7

Gentlemen thank you once more.

a.      I do not have an oscilloscope but I did a crude test on both Omron decoders with a multimeter. Applying 5v DC across the brown and blue(common ground) wires, I measured the voltage across black (A) and blue, then across white (B) and blue.
I then slowly rotated the spindle and observed voltage fluctuations between 0 and +0.1v DC.
This is what I would expect from the circuit diagram in the link from RJSakowski.
Also I would expect that the diode on the +5v feed (brown wire) should be well capable of surviving reversed polarity at the 5v level.
I opened one of the encoders and there was no obvious sign of burnt out components.
Therefore, absent any advice from you, I am going to assume that both encoders are working correctly.

b.     Moving the encoder input from J12 to J13 had no effect. I feel that there should be a switch change but the instructions say not.

c.     Knowing that you have a good configuration with v1.0.03 I flashed that version into memory and rebooted. The control panel now reads the correct version 1.0.03 but the rpm still only shows zero.

OK, I have had enough. I am sure it works but that I have screwed up somewhere. I feel as though it needs a switch set somewhere on the TI board. But I have spent about $500 on this and it has stopped being fun. I do not want to solder wires I just want to make swarf so I am going to hob some change gears and put the stepper motor on my mini mill.

Thanks for all your help.


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## ttabbal

I do have a scope and other electronics test gear. If you would like me to take a look at your parts, let me know. Perhaps I can help you at least identify parts with issues.


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## ian999

ttabbal, that is very kind of you to offer to test some parts.
However I live in Canada -- too far to drive, and the cost of postage, duty, general border issues would be so high that I could buy a new encoder!
Thanks again.


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## GunsOfNavarone

Anyone here have the Clough42 old metal bud box lid they don't need? Those of you that bought Cloughs PCB lid as well....


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## jlesser27

I have the box lid but have some layout marks on it. 


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## GunsOfNavarone

@jlesser27    I could skim cut it. I'll tell you from indicting mine in...they are not flat, so a skim would be helpful. I have mine I just finished you could have in trade. It's not flawless, its my first ever from fusion to final product, metal cnc project.


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## jlesser27

Yeah no problem. Shoot me your address. 


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## GunsOfNavarone

I guess I'll start a conversation with you and put it there? I don't want it public posted for bots and such...


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## GunsOfNavarone

ian999 said:


> Regarding the Clough42 ELS on a ML7
> 
> Gentlemen thank you once more.
> 
> a.      I do not have an oscilloscope but I did a crude test on both Omron decoders with a multimeter. Applying 5v DC across the brown and blue(common ground) wires, I measured the voltage across black (A) and blue, then across white (B) and blue.
> I then slowly rotated the spindle and observed voltage fluctuations between 0 and +0.1v DC.
> This is what I would expect from the circuit diagram in the link from RJSakowski.
> Also I would expect that the diode on the +5v feed (brown wire) should be well capable of surviving reversed polarity at the 5v level.
> I opened one of the encoders and there was no obvious sign of burnt out components.
> Therefore, absent any advice from you, I am going to assume that both encoders are working correctly.
> 
> b.     Moving the encoder input from J12 to J13 had no effect. I feel that there should be a switch change but the instructions say not.
> 
> c.     Knowing that you have a good configuration with v1.0.03 I flashed that version into memory and rebooted. The control panel now reads the correct version 1.0.03 but the rpm still only shows zero.
> 
> OK, I have had enough. I am sure it works but that I have screwed up somewhere. I feel as though it needs a switch set somewhere on the TI board. But I have spent about $500 on this and it has stopped being fun. I do not want to solder wires I just want to make swarf so I am going to hob some change gears and put the stepper motor on my mini mill.
> 
> Thanks for all your help.


Man! If you weren't in a different country, I'd say send me your Ti board and boost board, I'd plug it into my working system and figure it out. I REALLY feel like it's something simple/small. I feel your frustration. Maybe just take a step back, clear your head and come back in a week.


----------



## DoubleHelix

Has anyone added Jog to their ELS setup?  You wouldnt be able to do this while threading since it would not be synced but for just normal feed operations.


----------



## RJSakowski

I tried using the enable input to my driver for end of travel.  (electronic carriage stop)  If the driver is enabled while the spindle is still turning, weird things happen with the feed rate.  The lead screw might reverse or rotate with a speed different from that which has been set.  Stopping the spindle before enabling the driver will return thing to normal.  This is a driver issue and other drivers may behave differently.

If you are planning to use the driver enable to jog the lerad screw, use caution.


----------



## GunsOfNavarone

RJSakowski said:


> I tried using the enable input to my driver for end of travel.  (electronic carriage stop)  If the driver is enabled while the spindle is still turning, weird things happen with the feed rate.  The lead screw might reverse or rotate with a speed different from that which has been set.  Stopping the spindle before enabling the driver will return thing to normal.  This is a driver issue and other drivers may behave differently.
> 
> If you are planning to use the driver enable to jog the lerad screw, use caution.


Man RJ, you have a genius idea. Why wouldn't you be able to have some sort of limit switch? Perhaps in a magnet and place it where ever the thread operation ended or (more reasonably) where the feed ends for simple turning. I mean really, this is essentially CNC, why isn't it possible and super simple? You're saying, when you stopped the carriage moving forward, you had problems based on the spindle turning? Couldn't this some how be connected to a vfd to stop it as well? Why is it not an issue when using the ELS normally and stop at the end of a pass? Is the only way you can stop the carriage moving forward when threading is the run/stop switch? That's got to make if difficult where the threads end right up against the nut (with little to no gutter) I mean we still have the half nut, but stopping via the ELS would be great. Maybe 'll shoot Clough that question.


----------



## RJSakowski

GunsOfNavarone said:


> Man RJ, you have a genius idea. Why wouldn't you be able to have some sort of limit switch? Perhaps in a magnet and place it where ever the thread operation ended or (more reasonably) where the feed ends for simple turning. I mean really, this is essentially CNC, why isn't it possible and super simple? You're saying, when you stopped the carriage moving forward, you had problems based on the spindle turning? Couldn't this some how be connected to a vfd to stop it as well? Why is it not an issue when using the ELS normally and stop at the end of a pass? Is the only way you can stop the carriage moving forward when threading is the run/stop switch? That's got to make if difficult where the threads end right up against the nut (with little to no gutter) I mean we still have the half nut, but stopping via the ELS would be great. Maybe 'll shoot Clough that question.


My idea was to use a microswitch to disable the stepper driver which it did very reproducibly.  When I disengaged the half nut and manually backed off the microswitch, the driver was again enabled but the stepper was now running in reverse.  The driver apparently doesn't like being disabled while it is receiving step/direction signals.  Even if it did work properly, it would be of no use for threading as disabling the driver is the electrical equivalent of disengaging the gear train.  Synchronization is lost.

It does work for carriage feed though as synchronization is an issue.  I run to the stop and and disengage the half nuts and then back the carriage off the stop.  The lead screw starts in reverse and I trigger the stop again which starts it running in the forward direction.  It weorkss but is really of little utility as when I am turning with power feed, I will disengage my half nuts before the end of travel and finish manually to the stop or to a DRO position.

I have a mechanism to disengage the half nuts using an electrical stop in the works.  As things ease up,I'll be getting back to it and will publish it on HM at that time.


----------



## GunsOfNavarone

Hmmm... Maybe a programming thing for James. If a micro switch could send a signal to run a patch that just reversed direction on a VFD, Or, since the spindle and lead screw are no longer mechanically connected, just immediately reversed the lead screw direction? There has got to be SOMETHING there. This is CNC pretty much after all.
What would happen if the micro switch reversed the VFD and left the ELS alone? What would the ELS do if the spindle changed direction fairly quickly?
What if the micro switch shut down receiving signal from encoder? (spindle)
Help me out here brother, you're far smarterer than me!
I have seen some of the half nut disengaging setups (that leave manual control) WAY too much work!


----------



## RJSakowski

I don't have a VFD...yet.  I'm working on that now.  It is possible that Clough could work something into the code.  It starts to get complicated though.  Essentially, the code would have to recognize the trigger signasl, stop sending pulses to the driver but continue counting them and do some catch up later to restore synchronization.


----------



## DoubleHelix

Well from Clough's github it looks like it is in consideration:

*Future Goals*

While this project is starting out as a simple gearbox replacement, some features seem attractive, even for that simple case:

Threading/feeding up to a hard shoulder with automatic stop
Automatic recall and resync with hybrid threads (e.g. metric threads on an imperial leadscrew)


----------



## GunsOfNavarone

Yeah, I sent him a question based on a convo with others here about the auto stop about a week ago. Of course no answer, but if enough around here post that on his ELS youtube comments, maybe that will reignite his interest.


----------



## DoubleHelix

So far what I plan to try is a proximity sensor (copy of @mksj proximity sensor) connected to the VFD.  This will stop the spindle, encoder will send steps and thus stop the ELS movement.  

If you have the sensor stopping the ELS directly while spindle is still spinning then its a more complicated endeavour of syncing back up.


----------



## GunsOfNavarone

@DoubleHelix what VFD are you using? During my build/install I came across something that I remember thinking I could use for such a thing (ELS wasn't even a thought at that point) I'll have to look that up again & post here. At say 60 RPM, the spindle could be stopped in a second.


----------



## DoubleHelix

GunsOfNavarone said:


> @DoubleHelix what VFD are you using? During my build/install I came across something that I remember thinking I could use for such a thing (ELS wasn't even a thought at that point) I'll have to look that up again & post here. At say 60 RPM, the spindle could be stopped in a second.


Hitachi WJ200-022SF with a 35ohm 300W braking resistor.  1sec stopping shouldnt be a issue.  This is just theory since I have a lot to go before testing (still dont have 220V in the garage yet).


----------



## DoubleHelix

@GunsOfNavarone Just saw you were in Lakewood.  I'm sure at the pace I'm going you will beat me to the build but you'd be welcome to come over and check out my setup when I actually get there.


----------



## GunsOfNavarone

No F'n way! You're moving to Lakewood?!? Green Mountain to be exact! That. is. awesome! Hit me up when your here, I'll bring you a fruit basket er something! My VFD finished up many months ago. Its a Teco L510 and the resistor is built in and very weak. It works for low inertia though. Part of me wants to swap out to something that has an external resistor, I THINK that would be pretty easy.


----------



## kb58

Just an FYI,  someone's made a touchscreen interface for Clough42's ELS,


----------



## GunsOfNavarone

What does it even take to do that??? I know a touchscreen but...


----------



## ttabbal

Those Nextion screens are pretty easy to work with. There are even libraries for most platforms to drive them. I think I would rather stick with physical buttons, but it's a nice option.


----------



## ian999

OK, I am back. Finally I have it working by going back to basics and building it step by step on the bench with fresh wiring and new walwarts. I found a previous 5v walwart was actually giving out 17v so no wonder things were going awry.



Mechanically it is trivial. The encoder has an obvious place on the banjo driven from the tumbler gears. The stepper sits behind the right hand side of the bed just like Tony Jeffree placed it some 10 years ago, and drives the lead screw via a toothed belt. At both ends I kept the original parts and made brass bushings to fit timing gears with the tailstock end being counter bored to take the "Simmonds Nut". My lathe never had a hand wheel so I did not need to face that complication.



I did not need to drill any holes into the lathe and I can put it back to its original condition in about 15 minutes.



All of my problems came on the electronic side. The switching on the TI board gave a lot of problems as did flashing the board's memory. The software (TI's Code Composer Studio) is distinctly unfriendly. Everything is fine if everything works, but when things go off-track there is zero support. Essentially you must buy Clough42's daughter board, but he offers it very cheaply so that is not a problem. It is also a very good idea to buy the parts for the Control Panel from him, also very cheaply. My efforts with a control panel saw several displays smoke and sizzle under my lack of skills.



With his daughter board you are faced with making 60 solder joints and roughly another 50 depending on how you handle the wiring. This alone stretched my abilities considerably!



Instructions were sometimes unclear. S9 needs to be towards the CAN label. Directions to leave it at "Default" were not helpful as one of the three boards I purchased had the default position towards ALT. I used the suggested hybrid servo with a 4:1 feed and that should have meant programming in 4 microsteps and 1000 resolution, but I had to increase the microsteps to 16 before the speeds were correct.



So at the end of it all, you get to avoid change wheels and to be able to dial in pretty much any thread pitch or feed rate you desire, metric or imperial, and it looks quite cool! I need to add a few thread pitches eg 22 tpi for 5/16 BSF a Whitworth thread, but that should be no problem.



The project is clearly unfinished and we can all wonder what the next steps, if any, will be. Many thanks to RJS and Guns for trying to boost my morale.


----------



## ian999

Just a minor update on the Clough42 ELS.

I needed to add a 22 tpi option so I added a line in the file "tables.cpp".



{ .display = {BLANK, BLANK, ONE, EIGHT}, .leds = LED_THREAD | LED_TPI, TPI_FRACTION(180) },

{ .display = {BLANK, BLANK, ONE, NINE}, .leds = LED_THREAD | LED_TPI, TPI_FRACTION(190) },

{ .display = {BLANK, BLANK, TWO, ZERO}, .leds = LED_THREAD | LED_TPI, TPI_FRACTION(200) },

* { .display = {BLANK, BLANK, TWO, TWO}, .leds = LED_THREAD | LED_TPI, TPI_FRACTION(220) },*

{ .display = {BLANK, BLANK, TWO, FOUR}, .leds = LED_THREAD | LED_TPI, TPI_FRACTION(240) },

{ .display = {BLANK, BLANK, TWO, SIX}, .leds = LED_THREAD | LED_TPI, TPI_FRACTION(260) },





Save, flash and reboot.

22 tpi comes up on the Control Panel and actually gives a 22 tpi cut.

This has been the easiest part of dealing with this software.

Of course you can try any thread pitch you desire. I am now going to try loading BA threads which for some totally obscure Brit reason are all decimal inch threads!


----------



## GunsOfNavarone

@ian999 I'm curious, the "daughter board" of Clough's you speak of, this is the boost board? It seems to me there wasn't much soldering to do on this, in fact someone here just bent the 5 connectors that went to the display so they didn't have to de-solder and re-solder those. Being its only real job is to send a 3.0 v from the 5.5v supplied, there must be other ones available?


----------



## kb58

Yeah "daughter board" and "boost board" are referring to the same card that Clough42 fabricates and sells. It does a number of housekeeping chores like having a voltage regulator, EE memory chip (currently unused), and voltage level converters. My failing memory seems to recall something else, but it replaces around three separate circuits and really cleans up things.


----------



## ian999

Reply to Guns:

When you say "someone here just bent the 5 connectors" that was me. Rather than burn out another LED&KEY board in the control panel by trying to de-solder the 5 pin connector, I bent the pins over by about 60 degrees and pushed in the connectors I was using. However the length exposed was insufficient to hold the connectors securely so I pulled the end insulators off, soldered the ends to the 5 pin on the LED&KEY board then applied heat shrink tubing. Overall it is a bit thicker than Clough42's approach but it was easier for me. It still meant that there were 5 solder points to be done.

Regarding the daughter board/booster board, I suggest you look at it again. There are two 20 pin connector blocks (requiring 40 solder points), 4 solder points for the 5v supply, 6 for the stepper control connector, and 5 for feed to the control panel.

Including the control panel that adds up to 60 individual solder joints.


----------



## GunsOfNavarone

Man! I just don't remember soldering anything to the boost board but the 5 pin connector you just spoke of. The TI launch board wasn't much more either. I like soldering...maybe I had such a good time I'm blacking out that experience?


----------



## ian999

Guns, I don't like soldering. But I do like drinking and I have such a good time I often black out as well.


----------



## kb58

GunsOfNavarone said:


> Man! I just don't remember soldering anything to the boost board but the 5 pin connector you just spoke of...


During the Clough42 video where he assembled one of his boards, he mentioned that some lucky buyer would get that assembled unit. It's quite possible that you got it.


----------



## greenail

wow, this thread has a life of it's own.   I didn't intend it to be a single ELS specific thread but it seems everyone is using the clough42 board.

I recently found a very good write up of what looks like a solid implementation which addresses a few issues with the clough42 board which can be found here: https://github.com/prototypicall/Didge/blob/master/doc/How.md  Unfortunately the toolchain is gnu-arm and building it isn't quite as simple as an arduino sketch.  

I finally dusted off my original project and got to work finishing it.  I have it running on an esp32 with web configuration.  The multi core seems to be working well driving the web server, buttons, display, and stepper.  The step generation can also be offloaded to the RMT peripheral.  It's pre-alpha state is hooked up to the lathe and feeding.  Before I commit to the controller design I wanted to ask if anyone has a good interface they think is easy to use, it doesn't need to be an ELS, it could be any interface you can describe which would be good for lathe operation.

From my limited testing I see a few things:

1. in slave mode, where the lead screw is just slaved to the spindle and waits for the spindle to turn you only really need a mode selector, mode on/off and a left/right button to set the rotation direction.
2. When using a virtual stop things get more interesting.  You need a way to set the stops, a way to feed to the stops, and finally a way to jog to the stops.
3.  Jogging to a shoulder is difficult with no haptic feedback.  An encoder jog wheel (MPI like) would be handy but then you need an intuitive and easy way to set the steps per encoder click.  
4. I found a very interesting project to give haptic feedback for semi-manual machining.  https://hackaday.com/2020/03/24/turn-by-wire-is-a-machinists-sixth-sense/
5. Stout beefy levers seem better, i think I need the left/right controls to be a solidly mounted momentary-off-momentary switch with some big detents.  I've made m-off-m switches, anyone have a good design to share?
6. I just don't like touch screens.  there is no feedback and they can be fiddly.
7. blister buttons are no good, the rocketronics  ELS 4 looks very very capable and the UI on the screen is nice, but those buttons....


----------



## GunsOfNavarone

ian999 said:


> Just a minor update on the Clough42 ELS.
> 
> I needed to add a 22 tpi option so I added a line in the file "tables.cpp".
> 
> 
> 
> { .display = {BLANK, BLANK, ONE, EIGHT}, .leds = LED_THREAD | LED_TPI, TPI_FRACTION(180) },
> 
> { .display = {BLANK, BLANK, ONE, NINE}, .leds = LED_THREAD | LED_TPI, TPI_FRACTION(190) },
> 
> { .display = {BLANK, BLANK, TWO, ZERO}, .leds = LED_THREAD | LED_TPI, TPI_FRACTION(200) },
> 
> * { .display = {BLANK, BLANK, TWO, TWO}, .leds = LED_THREAD | LED_TPI, TPI_FRACTION(220) },*
> 
> { .display = {BLANK, BLANK, TWO, FOUR}, .leds = LED_THREAD | LED_TPI, TPI_FRACTION(240) },
> 
> { .display = {BLANK, BLANK, TWO, SIX}, .leds = LED_THREAD | LED_TPI, TPI_FRACTION(260) },
> 
> 
> 
> 
> 
> Save, flash and reboot.
> 
> 22 tpi comes up on the Control Panel and actually gives a 22 tpi cut.
> 
> This has been the easiest part of dealing with this software.
> 
> Of course you can try any thread pitch you desire. I am now going to try loading BA threads which for some totally obscure Brit reason are all decimal inch threads!


I don't foresee any need as of right now, but besides your example of the edit....doesn't that just give the LED screen to show the number 22? Don't you have to do any tables programing? The relation of spindle to stepper ratio? Is editing really that simple?


----------



## GunsOfNavarone

greenail said:


> wow, this thread has a life of it's own.   I didn't intend it to be a single ELS specific thread but it seems everyone is using the clough42 board.
> 
> I recently found a very good write up of what looks like a solid implementation which addresses a few issues with the clough42 board which can be found here: https://github.com/prototypicall/Didge/blob/master/doc/How.md  Unfortunately the toolchain is gnu-arm and building it isn't quite as simple as an arduino sketch.
> 
> I finally dusted off my original project and got to work finishing it.  I have it running on an esp32 with web configuration.  The multi core seems to be working well driving the web server, buttons, display, and stepper.  The step generation can also be offloaded to the RMT peripheral.  It's pre-alpha state is hooked up to the lathe and feeding.  Before I commit to the controller design I wanted to ask if anyone has a good interface they think is easy to use, it doesn't need to be an ELS, it could be any interface you can describe which would be good for lathe operation.
> 
> From my limited testing I see a few things:
> 
> 1. in slave mode, where the lead screw is just slaved to the spindle and waits for the spindle to turn you only really need a mode selector, mode on/off and a left/right button to set the rotation direction.
> 2. When using a virtual stop things get more interesting.  You need a way to set the stops, a way to feed to the stops, and finally a way to jog to the stops.
> 3.  Jogging to a shoulder is difficult with no haptic feedback.  An encoder jog wheel (MPI like) would be handy but then you need an intuitive and easy way to set the steps per encoder click.
> 4. I found a very interesting project to give haptic feedback for semi-manual machining.  https://hackaday.com/2020/03/24/turn-by-wire-is-a-machinists-sixth-sense/
> 5. Stout beefy levers seem better, i think I need the left/right controls to be a solidly mounted momentary-off-momentary switch with some big detents.  I've made m-off-m switches, anyone have a good design to share?
> 6. I just don't like touch screens.  there is no feedback and they can be fiddly.
> 7. blister buttons are no good, the rocketronics  ELS 4 looks very very capable and the UI on the screen is nice, but those buttons....


Ok....read it. At the end of the day, what are your thoughts and did you make any modifications based on that pages finding? I will have to read it AT LEAST one more time to get much understanding from it.


----------



## greenail

I wanted to post an update and ask for some feedback from folks.  I've been playing with haptic feedback and I think you could make a pretty intuitive ELS controller.  My requirement is to limit the buttons/knobs and be something you don't have to look at to operate.  The idea is to have a single "smart lever" which can act as a toggle, or 3 position switch, or variable detent rotary encoder, even have variable spring load per mode (e.g. rapid mode would have a stronger "virtual spring") etc etc.

 I'm wondering what folks think about the control setup I describe below?






P.S.  This morning I have fixed the oscillations in the PID loop in a very robust way.


----------



## Winegrower

I like the whole concept of what you folks are working on, but it’s not for me.   My lathe is easily switched to whatever feed and pitch needed just using levers, and after spending my entire career designing computers, processors, printers, disk drives, internet edge devices, control systems and software for all this, I am in no mood to mess up my hobby by pulling in a bunch of work issues.   

But I applaud your progress and enthusiasm!


----------



## greenail

Winegrower said:


> I like the whole concept of what you folks are working on, but it’s not for me.   My lathe is easily switched to whatever feed and pitch needed just using levers, and after spending my entire career designing computers, processors, printers, disk drives, internet edge devices, control systems and software for all this, I am in no mood to mess up my hobby by pulling in a bunch of work issues.
> 
> But I applaud your progress and enthusiasm!



Unfortunately my lathe came with a banjo designed for a different gear train.  It also lacked any clear documentation and the finest feed was very fast.  This thread isn't for folks who are happy with their existing gearboxes.


----------



## greenail

bumping this back to the bottom, still looking for feedback on how to leverage haptic feedback/input controls



greenail said:


> I wanted to post an update and ask for some feedback from folks.  I've been playing with haptic feedback and I think you could make a pretty intuitive ELS controller.  My requirement is to limit the buttons/knobs and be something you don't have to look at to operate.  The idea is to have a single "smart lever" which can act as a toggle, or 3 position switch, or variable detent rotary encoder, even have variable spring load per mode (e.g. rapid mode would have a stronger "virtual spring") etc etc.
> 
> I'm wondering what folks think about the control setup I describe below?
> 
> 
> 
> 
> 
> 
> P.S.  This morning I have fixed the oscillations in the PID loop in a very robust way.


----------



## kb58

Winegrower said:


> I like the whole concept of what you folks are working on, but it’s not for me.   My lathe is easily switched to whatever feed and pitch needed just using levers, and after spending my entire career designing computers, processors, printers, disk drives, internet edge devices, control systems and software for all this, I am in no mood to mess up my hobby by pulling in a bunch of work issues.
> 
> But I applaud your progress and enthusiasm!


Some of us just like building stuff , and in my case, my Takisawa TSL-800 came without any change gears, so it was a choice of not cutting threads, having gears made, or implementing an ELS. Like you, my electrical engineering and software background made me wary of complicating an otherwise simple tool. But I like mechanical things, and money-wise, it made sense to go this way, and it's working great.


----------



## RJSakowski

I would agree that simplifying the controls is highly desirable  when running the lathe or any machinery for that matter.  The switches Clough I/O panel are too small and too close together to avoid diverting your attention from the machining.  However, the only controls that I might be using while actually machining would be the FWD/REV and +/-.  Separating the FWD/REV into two separate switch would be nice in that it would eliminate a double press and/or the need to verify the state visually.  

I would like to see a OFF position as well so a three position switch would work for me.  A rapid function would be useful for power feed.  It couldn't happen with loss of sync for threading though.  

Ideally, those controls that I would use while machining would be conveniently located with large buttons sufficiently separated from each other to permit "blind" operation.

As to your smart lever concept, I would think that it could work once you developed the muscle memory.  I like to keep controls simple and having a one control does all is a bit troubling for me.  As an example, my Logitech mouse has the standard left click/right click/ center click/scroll functions but also has a left and right center click and two left side buttons.  Way too much for me.  I have disabled all but the basic functions.

However, you are designing a control for your own use so what I think is immaterial.  I do like the idea of a software defined switch.  Presumably, it wouldn't be that difficult to program in various modes so the control could be fit to the desired task at hand.  One thing that has to be considered when adding complexity to a machine is that a machine gone berserk can do a considerable amount of damage and /or be a safety hazard.  The Boeing 737 MAX is a good example of this.


----------



## Winegrower

My weird situation is “I wish I could build an electronic lead screw but I don’t want to”.


----------



## greenail

RJSakowski said:


> I would agree that simplifying the controls is highly desirable  when running the lathe or any machinery for that matter.  The switches Clough I/O panel are too small and too close together to avoid diverting your attention from the machining.  However, the only controls that I might be using while actually machining would be the FWD/REV and +/-.  Separating the FWD/REV into two separate switch would be nice in that it would eliminate a double press and/or the need to verify the state visually.
> 
> I would like to see a OFF position as well so a three position switch would work for me.  A rapid function would be useful for power feed.  It couldn't happen with loss of sync for threading though.
> 
> Ideally, those controls that I would use while machining would be conveniently located with large buttons sufficiently separated from each other to permit "blind" operation.
> 
> As to your smart lever concept, I would think that it could work once you developed the muscle memory.  I like to keep controls simple and having a one control does all is a bit troubling for me.  As an example, my Logitech mouse has the standard left click/right click/ center click/scroll functions but also has a left and right center click and two left side buttons.  Way too much for me.  I have disabled all but the basic functions.
> 
> However, you are designing a control for your own use so what I think is immaterial.  I do like the idea of a software defined switch.  Presumably, it wouldn't be that difficult to program in various modes so the control could be fit to the desired task at hand.  One thing that has to be considered when adding complexity to a machine is that a machine gone berserk can do a considerable amount of damage and /or be a safety hazard.  The Boeing 737 MAX is a good example of this.




Thanks for the feedback.  Looking to brainstorm with folks so any ideas you have are welcome.    I also hope my lathe isn't quite like a boeing 737 but I do want it to be safe!

Reading your post i wonder about a 5 position switch mode for jogging:




Rapid Left--------Jog Left--------Do nothing--------Jog Right--------Rapid Right|​​|​|​​|​torque 10​torque 3​torque 10

It is hard to describe in the video but the little gimbal motor puts out decent torque  and it is good feedback.

For threading you could just omit the 2 left detents and keep the jog right/rapid right...


----------



## RJSakowski

greenail said:


> Thanks for the feedback.  Looking to brainstorm with folks so any ideas you have are welcome.    I also hope my lathe isn't quite like a boeing 737 but I do want it to be safe!
> 
> Reading your post i wonder about a 5 position switch mode for jogging:
> 
> Rapid Left  -------- Jog Left ------- Do nothing --------  Jog Right ------ Rapid Right
> |                           |                               |                               |
> torque 10                          torque 3                                   torque 10
> 
> It is hard to describe in the video but the little gimbal motor puts out decent torque  and it is good feedback.
> 
> For threading you could just omit the 2 left detents and keep the jog right/rapid right...


Jogging isn't a concern for me as I can disengage the half nuts and crank the carriage manually.  If it were a full CNC machine, then it would be.
While threading, none of the above can be done without losing sync.  It would be nice to have a rapid return feature while threading and I had given some thought to it but couldn't come up with anything that would work.  

Not a problem when Imperial threading on an Imperial lathe or metric threading on a metric lathe as the time proven method of releasing the half nuts and cranking the carriage manually works but this doesn't work when mixing inch and metric.

I had thought about using the enable function on the stepper driver along with a sensor to detect the end of a pass but gave it up after realizing it effectively took the electronic gear train out of gear and sync was lost.  I could still use it for power feed though. 

For the purpose of accurately threading to a shoulder, I decided to go with a mechanical solution.  Actually, electromechanical as a sensor would activate a solenoid which would disengage the half nuts.  The design is done and I have to start cutting metal.


----------



## Qtron

RJSakowski said:


> Jogging isn't a concern for me as I can disengage the half nuts and crank the carriage manually.  If it were a full CNC machine, then it would be.
> While threading, none of the above can be done without losing sync.  It would be nice to have a rapid return feature while threading and I had given some thought to it but couldn't come up with anything that would work.
> 
> Not a problem when Imperial threading on an Imperial lathe or metric threading on a metric lathe as the time proven method of releasing the half nuts and cranking the carriage manually works but this doesn't work when mixing inch and metric.
> 
> I had thought about using the enable function on the stepper driver along with a sensor to detect the end of a pass but gave it up after realizing it effectively took the electronic gear train out of gear and sync was lost.  I could still use it for power feed though.
> 
> For the purpose of accurately threading to a shoulder, I decided to go with a mechanical solution.  Actually, electromechanical as a sensor would activate a solenoid which would disengage the half nuts.  The design is done and I have to start cutting metal.


Hiya Bob, lost contact w you! Glad u r okWatched Greenail's vid. Clever, like the haptic concept very much, was always a nag in my mind re imminent machine crash, esp after having a parting off tool explode.
But I dont get how it would work with threading..
If the pass is say, too deep into the work piece, & the ave stepper current is too hi, what would the haptic sense be used to do?  Slow the spindle, & therefore the stepper? Not necessarily a good thing to do, is it?
...
BTW, re rapid feed, my lathe has a power feed drive train, that could be used as a rapid feed.
But for those that dont have that feature,  running the leadscrew at a fast pace for rapid, wouldnt that simply add to premature wear of the half nuts?


----------



## RJSakowski

Qtron said:


> Hiya Bob, lost contact w you! Glad u r okWatched Greenail's vid. Clever, like the haptic concept very much, was always a nag in my mind re imminent machine crash, esp after having a parting off tool explode.
> But I dont get how it would work with threading..
> If the pass is say, too deep into the work piece, & the ave stepper current is too hi, what would the haptic sense be used to do?  Slow the spindle, & therefore the stepper? Not necessarily a good thing to do, is it?
> ...
> BTW, re rapid feed, my lathe has a power feed drive train, that could be used as a rapid feed.
> But for those that dont have that feature,  running the leadscrew at a fast pace for rapid, wouldnt that simply add to premature wear of the half nuts?


As I said, I don't believe that it will work with threading.  You can't change the relationship of the spindle with the lead screw without losing sync.  That includes changing lead screw speed as well as reversing the lead screw.  This would be akin to changing the gearing in the gear train.  The half nuts are unique in that regard because we have a mechanism that keeps track of screw rotation and we are disengaging after the lead screw so it doesn't  lose sync.

For threading, any remedy for problems caused by too aggressive a cut would have to be at the spindle, before the gear train in order to maintain sync.  Basically, slow or stop the spindle.  For power feed, we can decrease the feed rate or reverse it at will without penalty.

I am really not concerned about having a rapid power feed.  It is a simple matter to disengage the half nuts and manually crank the carriage.  I actually don't use power feed all that much because historically, it was a PITA to change gears  in the gear train so for fifty years, I just moved the carriage manually.  To a certain extent, I like the control that fully manual operation provides.  The ELS has made it much more convenient to change gears and I am slowly adjusting to using power feed but for many operations, I don't even activate the ELS. (My system is set up so the power to the driver is switched separately so I can use the spindle speed display without turning the lead screw.)

If more advanced controls were desired, the Rocketronics system would be a better choice.  It is a quasi CNC, detecting spindle orientation and adding power cross feed, enabling a fully automatic operation for both turning and threading.  But then, you are close to full CNC.  The disadvantage of the Rocketronics system is that you can't easily set up a new routine as you can by writing some G-code.

For a brief moment, I had considered going CNC.  It would increase the versatility of the lathe.  I resisted beaus I like manual operation.  I am fortunate that I have a CNC mill and if I really needed to have the capability that a CNC lathe offers, I can run the mill as a vertical CNC lathe.


----------



## greenail

Qtron said:


> Hiya Bob, lost contact w you! Glad u r okWatched Greenail's vid. Clever, like the haptic concept very much, was always a nag in my mind re imminent machine crash, esp after having a parting off tool explode.
> But I dont get how it would work with threading..
> If the pass is say, too deep into the work piece, & the ave stepper current is too hi, what would the haptic sense be used to do?  Slow the spindle, & therefore the stepper? Not necessarily a good thing to do, is it?
> ...
> BTW, re rapid feed, my lathe has a power feed drive train, that could be used as a rapid feed.
> But for those that don't have that feature,  running the leadscrew at a fast pace for rapid, wouldn't that simply add to premature wear of the half nuts?



Just to clarify my thinking:  The brainstorming around a haptic input controller was not intended to solve all problems.  The main problem it should try to solve is the complexity of the interface.







7 tiny buttons vs 2 or 3 buttons and 1 lever is the idea with most of the interaction being with the lever.





This one has 30 buttons!

The complexity traded off is perhaps the fact that the fewer controls become modal, meaning they behave different depending on the mode.  Many modes are possible but too many modes creates it's own complexity.  You "could" imagine a threading mode which would not fix issues with your depth of cut but would:

1. let you keep the half nuts engaged.
2. physically move to the neutral position when the thread pass is done, prompting you to retract the cutter. 
3.  allow you to jog (one detent right) or rapid (two detents right more torque on the 2nd detent) back to your thread start without having to stop/reverse/stop/reverse the spindle
4. physically move the control lever back to the neutral position when the thread start is reached if you have set a virtual stop.
5.  the ELS syncs the thread start, no thread dial needed.
6. Offsets the cutter each pass to obviate the need to fiddle with a compound.

Ideally you would not have to ever look at the controller, your hands would tell you everything you need to know and you could focus on the thread you are cutting.  Not having to look at it is the goal here.

This may not work well in practice, it is just an idea exploring what you can do when you can position the control lever and reconfigure it's detents and the detent strength arbitrarily.  If you didn't want to rapid you could use at thread dial and disengage the halfnuts.  That choice really has no impact on the discussion i'm trying to have.  Saying "that is stupid, i've been doing it this way for 50 years" isn't really helpful when trying to develop something new.  It may in fact turn out this idea doesn't go anywhere.  I'd like to explore it a bit before I give up on it.


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## RJSakowski

greenail said:


> Just to clarify my thinking:  The brainstorming around a haptic input controller was not intended to solve all problems.  The main problem it should try to solve is the complexity of the interface.
> 
> View attachment 346275
> 
> 
> 7 tiny buttons vs 2 or 3 buttons and 1 lever is the idea with most of the interaction being with the lever.
> 
> View attachment 346276
> 
> This one has 30 buttons!
> 
> The complexity traded off is perhaps the fact that the fewer controls become modal, meaning they behave different depending on the mode.  Many modes are possible but too many modes creates it's own complexity.  You "could" imagine a threading mode which would not fix issues with your depth of cut but would:
> 
> 1. let you keep the half nuts engaged.
> 2. physically move to the neutral position when the thread pass is done, prompting you to retract the cutter.
> 3.  allow you to jog (one detent right) or rapid (two detents right more torque on the 2nd detent) back to your thread start without having to stop/reverse/stop/reverse the spindle
> 4. physically move the control lever back to the neutral position when the thread start is reached if you have set a virtual stop.
> 5.  the ELS syncs the thread start, no thread dial needed.
> 6. Offsets the cutter each pass to obviate the need to fiddle with a compound.
> 
> Ideally you would not have to ever look at the controller, your hands would tell you everything you need to know and you could focus on the thread you are cutting.  Not having to look at it is the goal here.
> 
> This may not work well in practice, it is just an idea exploring what you can do when you can position the control lever and reconfigure it's detents and the detent strength arbitrarily.  If you didn't want to rapid you could use at thread dial and disengage the halfnuts.  That choice really has no impact on the discussion i'm trying to have.  Saying "that is stupid, i've been doing it this way for 50 years" isn't really helpful when trying to develop something new.  It may in fact turn out this idea doesn't go anywhere.  I'd like to explore it a bit before I give up on it.


You cannot interrupt the drive train while threading with the Clough ELS; either mechanically or electronically.  Doing so will result in the stepper driver losing its reference.  My understanding of the Clough logic is that counts are totaled from the start of threading, with packets subtracted from time to time to keep the count within range and some error correction is used.  It does not track actual orientation od the spindle.  

If you think about it what is required to successfully cut a thread, when the spindle is ina particular orientation, there is a define set positions of the carriage allowed.  That set is uniformly spaced by a distance equal to the thread pitch.  If you disconnect the lead screw driver from the chain, you will destroy that link.   The same if you reverse the direction or change the feed rate/pitch.  You can verify the latter two easily with the existing Clough ELS.  When you reach the end of a pass, reverse the feed and back the cutter out and back the carriage up for another pass.  The consequences of changing the feed rate or pitch is obvious enough not to require an actual run.

This is not to say that there isn't merit in your haptic control system.  Just to say that for threading, there is no need to mess with any controls once set.  As to adding extra utility, 

I would like to see an electronic auto stop feature.  My attempt to do this in a straight forward manned using the driver enable failed.  For my driver at least, the order of operation is enable followed by direction followed by pulse.  If pulses are being sent when the driver is enable, it goes haywire.  It may be possible to gain access within the Clough firmware so that the pulse and direction signal are disabled when the enable output is disabled.  In fact, it is probably being done for  the forward/reverse function already.  I'm not literate enough in the software language to ferret this out.


----------



## greenail

I'm not talking about Clough42's implementation.  I started this thread to generally talk about ELS, somehow 80% of the posts are about Clough42's nice ELS but this is just one way to skin the cat.  I have my own implementation and I can do whatever I want with it.



RJSakowski said:


> If you think about it what is required to successfully cut a thread, when the spindle is ina particular orientation, there is a define set positions of the carriage allowed.  That set is uniformly spaced by a distance equal to the thread pitch.  If you disconnect the lead screw driver from the chain, you will destroy that link.   The same if you reverse the direction or change the feed rate/pitch.  You can verify the latter two easily with the existing Clough ELS.  When you reach the end of a pass, reverse the feed and back the cutter out and back the carriage up for another pass.  The consequences of changing the feed rate or pitch is obvious enough not to require an actual run.



Again, you are stuck thinking about Clough's implementation where he is only trying to simulate change gears.  This simplifies the implementation but it is a very limited approach.  My controller keeps track of the spindle position, it can "wait" for the right time to re-engage leadscrew motor without the user having to do anything.  



RJSakowski said:


> My attempt to do this in a straight forward manned using the driver enable failed.



This doesn't work because the motor loses position when you disable the driver.  You can stop driving the motor without losing position.  You don't want to disengage the half nuts because this will lose the sync between the spindle encoder, the carriage position, and the controller.  Assuming the lead screw stays engaged you can then rapid back to your thread start manually, or even better  if you have set a virtual stop my controller can do it for you.  Then it simply needs to calculate when to re-engage the motor.  It is just like using a thread dial but you don't disengage the half nuts.  I thought I described this above but it seems words have failed me


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## RJSakowski

Sorry, I thought we were talking about the Clough ELS.  If your controller reads the position of the spindle, then yes, it is possible to disengage the motor and properly re-engage it.


----------



## AlanB

I also think the Clough42 ELS didn't go quite far enough. Having a spindle encoder with synch pulse, and being able to stop the carriage motion at specific memorized spots, as well as reacting to a stop input would be excellent, without going to a full CNC setup. Definitely have those on my list for an Electronic Lead Screw if I make one. I was looking at a 600 mhz Teensy board the other day that can be programmed with Arduino tools, much easier to work with than the proprietary licensed Texas Instruments software. As I recall the Teensy has real encoder inputs as well. More than one way to implement this stuff. Good to see other implementations to think about.


----------



## greenail

AlanB said:


> I also think the Clough42 ELS didn't go quite far enough. Having a spindle encoder with synch pulse, and being able to stop the carriage motion at specific memorized spots, as well as reacting to a stop input would be excellent, without going to a full CNC setup. Definitely have those on my list for an Electronic Lead Screw if I make one. I was looking at a 600 mhz Teensy board the other day that can be programmed with Arduino tools, much easier to work with than the proprietary licensed Texas Instruments software. As I recall the Teensy has real encoder inputs as well. More than one way to implement this stuff. Good to see other implementations to think about.



The teensy 4 is a beast!

The stm32 "blue pill" also has hardware quadrature encoders and is only a few bucks.  The "black pill" is $4 and is a bit faster/more capable. 

My ELS is using the esp32 which has multiple cores and you can offload the button/input management and wifi while also doing the step generation.  You can also generate the steps with the RMT peripheral or expand the IO by using the i2s peripheral and a few shift registers.  This is what Bart Dring's GRBL implementation does and it works well.  IMHO having wifi allows you to use your phone to configure the machine parameters and simplifies the overall UI by quite a lot since you rarely need to configure those parameters.  Lots of buttons can be omitted.  This then goes back to my idea of using a small gimbal motor with haptics to provide the majority of the user inputs.


----------



## AlanB

There's a lot of good hardware out there. Part of the process is choosing what one wants to work with in terms of tools. Many good choices.

One annoying thing is how quickly some of these development tools "corrode". A few years down the road they have changed so much they don't work anymore on previously developed projects. Used to use raw AVR chips and development tools, was nice to have a real "C" compiler for a whole range of small inexpensive chips. Arduino came along and made the tools easier to keep working, though they did break things a few times. It is nice to read completely through the hardware documentation, unfortunately now that's become many thousands of pages for each chip, not really practical to deeply understand all the various parts anymore. I still have one of the TI motor development kits that used open hardware on the shelf here, but they've abandoned that route. My next project along these lines is to put LinuxCNC and Mesa cards in control of my PM-728VT mill, then perhaps after that I'll get a new lathe to tinker with. Too many irons in the fire already... Best of luck with your ELS, I'll be following along.


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## greenail

I have an initial prototype of my webUI working.  Lots to do but I'm making steady progress.


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## GunsOfNavarone

Neat!


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## Sturgo

Look up clough 42 on YouTube 
He has a extensive video series on it and is selling new circuit boards to run the whole thing and where to buy the rest of the parts.


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## RJSakowski

Sturgo said:


> Look up clough 42 on YouTube
> He has a extensive video series on it and is selling new circuit boards to run the whole thing and where to buy the rest of the parts.



See post 11 in this thread.  The majority of posts in this thread have been about Clough42's ELS.


----------



## greenail

RJSakowski said:


> See post 11 in this thread.  The majority of posts in this thread have been about Clough42's ELS.



maybe you guys should make a  Clough42's ELS thread.  This thread was not intended to be that.  He said "neat" and you guys threadjacked.


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## RJSakowski

I'm sorry you feel that your thread was hijacked.  You sort of opened the door when you asked about the state of the art for an ELS. I got into the discussion when there were 46 previous posts, many regarding the Clough ELS

There was a short lived thread specifically devoted to the Clough42  ELS started last February.  Unfortunately, much of the useful information is already located in your thread.  A search for Clough42 will pop up your thread more than any other from the shear abundance of posts.   This forum has a tremendous wealth of information but it gets bogged down by the shear volume.

In spite of my having already installed the Clough42 ELS, I am following your progress and am looking forward to seeing your final implementation.  .


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## kb58

Regardless of solution, if the purpose of an ELS is to be a tool, the user interface can be something of a slippery slope, turning it into a project. Yeah, Clough42's approach is sort of old-school, but it does the job and lets me get on with things.


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## AlanB

I don't know what is customary on this forum, but it is common in other forums to split out a subtopic, and moving the Clough42 postings from this topic into the other thread that is already about that topic might be appropriate. Collect like information. It helps both the people looking for the Clough42 ELS info and those looking for "other" ELS info. It is a bit of work for a moderator, unfortunately.


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## GunsOfNavarone

Yeah, I'm sure I am one of the many that lead this "Electronic Lead Screw" thread back to....well, you know. I apologize for that and honestly, this thread comes up (probably) number one or close to it if you search that name. I think what you are doing is extremely cool and would suggest you start a fresh thread with the build from ideal to where it is now (and hopefully a final product) It definitely deserves it's own recognition. Just about everything you're doing with it, I'd love to incorporate into mine (though I think it's above my comfort level.) I look forward to that thread..


----------



## greenail

More progress.  Synchronized feed to a position is now working.


----------



## Qtron

greenail said:


> More progress.  Synchronized feed to a position is now working.


Fantastic work, wish I could write code!
Really looking FWD to end result.
A world beater!
An Aussie nerd watching & waiting patiently.


----------



## greenail

Qtron said:


> Fantastic work, wish I could write code!
> Really looking FWD to end result.
> A world beater!
> An Aussie nerd watching & waiting patiently.



you are the only thing stopping you from learning to write code!

I'm self taught, I started with perl in 1996 and bought a bunch of books.  Then I learned java, then ruby, then elixir and erlang, then elm and a tiny bit of haskel.  Javascript is a language but then you have to learn the framework, jquery was first dc.js with d3.js and crossfire.js, next was angular.js, and react.js and learning about all the transpilers and minifiers like babel and brunch.js,  4 years ago I started to learn c and c++ on embedded where people seem to ignore all of the rules of modern programming like writing tests and using abstractions, seems many want you bitshifting and staying close to the assembly.

Moral to the story is that now I'm mediocre in all of them but you have to start somewhere!  

Being serious for a moment, there has never been a better time to learn something new.  It was much harder before we had all of the resources we now have on the internet.


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## 7milesup

greenail said:


> I'm self taught, I started with perl in 1996 and bought a bunch of books. Then I learned java, then ruby, then elixir and erlang, then elm and a tiny bit of haskel. Javascript is a language but then you have to learn the framework, jquery was first dc.js with d3.js and crossfire.js, next was angular.js, and react.js and learning about all the transpilers and minifiers like babel and brunch.js, 4 years ago I started to learn c and c++ on embedded where people seem to ignore all of the rules of modern programming like writing tests and using abstractions, seems many want you bitshifting and staying close to the assembly.



Was that in English? 
Even coming from a guy that originally started out in college (1984) with computer programming, that all seemed overwhelming.
Oh, I started in Fortran, until I switched to flying airplanes.  LOL


----------



## GunsOfNavarone

Wish I had the attention span. I really thought many of these start/stop needs could be attained at some point from my ELS, but it sounds as if it has limitations that won't allow this sort of thing. I have no remorse, but if you ever get a working model, that is easily explained in how to recreate, I could very well be on that band wagon.


----------



## GunsOfNavarone

Wish I had the attention span. I really thought many of these start/stop needs could be attained at some point from my ELS, but it sounds as if it has limitations that won't allow this sort of thing. I have no remorse, but if you ever get a working model, that is easily explained in how to recreate, I could very well be on that band wagon.


----------



## Autodidact

Briney Eye said:


> You found me.  I don't have any backlash compensation because it's not CNC, just a programmable "gearbox".  The number of pitch selections is arbitrary.  I've implemented every pitch that I could find in online pictures of lathes, and every tap available from McMaster-Carr.  I stopped short of having an arbitrary programmable option, but it would be possible.  I did limit it to 4tpi just because I have a small lathe.  That's getting to be some serious depth of cut, and I have already noticed some "hiccups" cutting an 8tpi Acme thread in 1144.  I'm waiting for more timing pulleys and belts so that I can gear it down from the current 4:1 ratio between the stepper and the screw.  I'm planning to test it at 5-, 6- and 8-to-1.
> 
> I still have more to do.  The touch screen is great for a lot of things, but on-the-fly feed direction control needed something more tactile, so I've added a toggle switch mounted in front of the headstock.  I quickly programmed it to control the direction, but have to add jogging support still.  I just got sidetracked by actually making some things.
> 
> I think it would be cool to do cut knurling, so I'm also thinking of adding support for multi-start threads, but that's a ways off yet.  I've only used half the RAM on the Mega so far, so there's still room to squeeze more features in .  I promise to make at least a basic version of the code available at some point when I'm satisfied with it.
> 
> -Jon
> [/QUOTE





Briney Eye said:


> You found me.  I don't have any backlash compensation because it's not CNC, just a programmable "gearbox".  The number of pitch selections is arbitrary.  I've implemented every pitch that I could find in online pictures of lathes, and every tap available from McMaster-Carr.  I stopped short of having an arbitrary programmable option, but it would be possible.  I did limit it to 4tpi just because I have a small lathe.  That's getting to be some serious depth of cut, and I have already noticed some "hiccups" cutting an 8tpi Acme thread in 1144.  I'm waiting for more timing pulleys and belts so that I can gear it down from the current 4:1 ratio between the stepper and the screw.  I'm planning to test it at 5-, 6- and 8-to-1.
> 
> I still have more to do.  The touch screen is great for a lot of things, but on-the-fly feed direction control needed something more tactile, so I've added a toggle switch mounted in front of the headstock.  I quickly programmed it to control the direction, but have to add jogging support still.  I just got sidetracked by actually making some things.
> 
> I think it would be cool to do cut knurling, so I'm also thinking of adding support for multi-start threads, but that's a ways off yet.  I've only used half the RAM on the Mega so far, so there's still room to squeeze more features in .  I promise to make at least a basic version of the code available at some point when I'm satisfied with it.
> 
> -Jon




Did you end up making the knurling code?  I spent a fair amount of time programming a Mega as a control system and found it fairly capable.


----------



## greenail

Autodidact said:


> Did you end up making the knurling code?  I spent a fair amount of time programming a Mega as a control system and found it fairly capable.


How would you imagine the knurling would work?  If it is just like a multistart thread I don't think it would be that hard.  I have start synchronization working in my ELS project now.


----------



## Hard_ware

Nice!!!   plus multiple sync points +1
A wired pendant or control box interface would be nice once you get things worked out using gui.

The ELS to avoid changing gears is ok if changing gears bothered you. 
I think the benefit of the els is not cranking a carriage handle.
If I didn't want to crank any handles then full CNC is the ticket.
The ELS being sync'd to the spindle is a must.
Closed loop stepper motors, 3-phase for position measurement.
 Having a start position and a stop position would be a must.
Having a return to start button would be great.  A manual L and R feed(speed adjustable) to cut or set start and stop points.

If you think about what motions you do on the lathe, to face you crank the cross slide,  after that is turning , move cross slide to start point and start turning cut, stop back out or not, move carriage back to start and repeat.
With a small lathe you can't make deep cuts, so it's repeat repeat repeat.
Cutting threads all day and different threads constantly I don't buy it.
Depending on what you make it's usually a handful of different threads you will ever cut.
So making an electronic lead screw and cost vs 3 min to change gears for a thread pitch is more of a novelty then time saver.
Only exception is cutting Metric on Imperial LS or vice versa, not being able to disengage and reengage the LS sucks and slows the process down.  
But turning will be used for every part you make on the lathe. 
Imagine pressing a button go then return then crank cross slide in a bit now press go then return button and turn in a bit.
Not much cranking. With TouchDRO you just line up the green crosshair with your saved targets in your workspace set start and stop on the ELS and off you go. Correlating the stepper position counters to a absolute calibrated position like a DRO, start and stop points could be entered on the Z axis from prints or TouchDRO workspace. 



https://imgur.com/QULIva7


Having a set start point and set stop point and a go/return, only cross slide needs to be turned in each pass for depth of cut.
If you need to set a new start point bump the L or R and set it. 

This paired with touch DRO graphic workspace is about as far as you could go short of full CNC.
One knob on the lathe to crank 

Teensy4.0 look like a beast!

PS we have the same lathe 8x16 38mm bore.
I made a gear chart for gear combo's, I cut 24 and 28 TPI no problem.
1mm all day long as you can't screw it up with a metric lead screw


----------



## Qtron

greenail said:


> How would you imagine the knurling would work?  If it is just like a multistart thread I don't think it would be that hard.  I have start synchronization working in my ELS project now.


Hello Greenail, hope ur well, hows it all going.. Any updates?


----------



## greenail

Qtron said:


> Hello Greenail, hope ur well, hows it all going.. Any updates?



I've been working on my grinder and my new CNC build.  No big updates but I have one person getting his lathe setup and I should be getting some feedback soon.  I've been using my setup regularly and it is working great with a few things to note.

1. quick and easy way to turn off the stepper is handy if you have a hand wheel on your lead screw.
2. my encoder gear turned out to be the wrong tooth count (missed it by 2) so I need to print a new one before I start thread testing again.
3.  the design of the haptic controller communication interface stalled me out a bit since I don't really know what it should look like.
4.  While the haptic controller idea is fun it actually doesn't need a physical controller, controlling it via a phone or tablet works great.

I'll likely start writing more code and adding features when I get feedback from the new user or when I need to turn some threads.  if anyone wants to help out with testing they may want to check out the setup thread here.  https://github.com/jschoch/ESPels/issues/4


----------



## greenail

I need to make an adapter for my NSK ATC spindle and thus I need to cut some threads which leads me back into working on my ELS.  Looking for some feedback.

This page has a good overview of the different threading strategies used in CNC threading:  http://www.mitsubishicarbide.com/en...ing/tec_threading_guide/tec_threading_methods


To sum it up the ELS should offset the cutter based on the strategy, however since there may be no X feeding the threading depth is somewhat arbitrary.  My current thinking is for the user to enter the number of passes they want and for the user interface to display a table showing the infeeds based on the number of passes and rely on the user to tell the ELS when he has moved to the next pass.  So for example:

1mm thread pitch, 4 passes, strategy flank:

Pass 1: infeed .3mm radius, offset: 0
Pass 2: infeed .16, offset .25
Pass 3: infeed .12, offset .5
Pass 4: infeed .11, offset .75

Is this confusing?


----------



## Qtron

Briney Eye said:


> You found me.  I don't have any backlash compensation because it's not CNC, just a programmable "gearbox".  The number of pitch selections is arbitrary.  I've implemented every pitch that I could find in online pictures of lathes, and every tap available from McMaster-Carr.  I stopped short of having an arbitrary programmable option, but it would be possible.  I did limit it to 4tpi just because I have a small lathe.  That's getting to be some serious depth of cut, and I have already noticed some "hiccups" cutting an 8tpi Acme thread in 1144.  I'm waiting for more timing pulleys and belts so that I can gear it down from the current 4:1 ratio between the stepper and the screw.  I'm planning to test it at 5-, 6- and 8-to-1.
> 
> I still have more to do.  The touch screen is great for a lot of things, but on-the-fly feed direction control needed something more tactile, so I've added a toggle switch mounted in front of the headstock.  I quickly programmed it to control the direction, but have to add jogging support still.  I just got sidetracked by actually making some things.
> 
> I think it would be cool to do cut knurling, so I'm also thinking of adding support for multi-start threads, but that's a ways off yet.  I've only used half the RAM on the Mega so far, so there's still room to squeeze more features in .  I promise to make at least a basic version of the code available at some point when I'm satisfied with it.
> 
> -Jon


Hi Jon,
Lost contact w you;
Hope U are well..and not snowed under!
Any ELS updates since we spoke abt 6 months ago?
Cheers,
Qtron


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## Qtron

greenail said:


> I need to make an adapter for my NSK ATC spindle and thus I need to cut some threads which leads me back into working on my ELS.  Looking for some feedback.
> 
> This page has a good overview of the different threading strategies used in CNC threading:  http://www.mitsubishicarbide.com/en...ing/tec_threading_guide/tec_threading_methods
> 
> 
> To sum it up the ELS should offset the cutter based on the strategy, however since there may be no X feeding the threading depth is somewhat arbitrary.  My current thinking is for the user to enter the number of passes they want and for the user interface to display a table showing the infeeds based on the number of passes and rely on the user to tell the ELS when he has moved to the next pass.  So for example:
> 
> 1mm thread pitch, 4 passes, strategy flank:
> 
> Pass 1: infeed .3mm radius, offset: 0
> Pass 2: infeed .16, offset .25
> Pass 3: infeed .12, offset .5
> Pass 4: infeed .11, offset .75
> 
> Is this confusing?


Offset = ?


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## greenail

greenail said:


> I need to make an adapter for my NSK ATC spindle and thus I need to cut some threads which leads me back into working on my ELS.  Looking for some feedback.
> 
> This page has a good overview of the different threading strategies used in CNC threading:  http://www.mitsubishicarbide.com/en...ing/tec_threading_guide/tec_threading_methods
> 
> 
> To sum it up the ELS should offset the cutter based on the strategy, however since there may be no X feeding the threading depth is somewhat arbitrary.  My current thinking is for the user to enter the number of passes they want and for the user interface to display a table showing the infeeds based on the number of passes and rely on the user to tell the ELS when he has moved to the next pass.  So for example:
> 
> 1mm thread pitch, 4 passes, strategy flank:
> 
> Pass 1: infeed .3mm radius, offset: 0
> Pass 2: infeed .16, offset .25
> Pass 3: infeed .12, offset .5
> Pass 4: infeed .11, offset .75
> 
> Is this confusing?



here's the new table display for threading without a compound.






Getting close to releasing a beta, let me know if you want to test it out.


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## Qtron

greenail said:


> here's the new table display for threading without a compound.
> 
> 
> 
> 
> 
> 
> Getting close to releasing a beta, let me know if you want to test it out.


Fantastic Greenail look FWD to end result.
But will need info like how the tablet connects to the control board etc. Marvellous!
U have taken ELS into 21st century with cream on top! Cheers
Agree re no topslide extra stabilty too, esp on my old clunker.

i suppose the entire lines of offset & incremental feed & Total feed decimal places will be truncated on the display to 
not dazzle the user?


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## greenail

Qtron said:


> Fantastic Greenail look FWD to end result.
> But will need info like how the tablet connects to the control board etc. Marvellous!
> U have taken ELS into 21st century with cream on top! Cheers
> Agree re no topslide extra stabilty too, esp on my old clunker.
> 
> i suppose the entire lines of offset & incremental feed & Total feed decimal places will be truncated on the display to
> not dazzle the user?



the esp32 has wifi builtin as well as bluetooth, it connects via websockets for quick updates.  The page is "serverless" and you just plug in the IP address of the ELS and it connects.

decimal places is easy to clean up, but as with everything there are always lots of easy fixes...


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## Qtron

Hope you are well..
Thanks for explaining.
Has it been 'released' ?


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## greenail

Qtron said:


> Hope you are well..
> Thanks for explaining.
> Has it been 'released' ?



not sure what you are asking, it is available but I need some testers.  I've been using it for a few months without issue.


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## Qtron

Thankyou for your reply - just asking if it is in a usable state- which it must be!
Yes would love to try it 
is all the info avail, re how to get it into an ESP32, I have never used one, have only prog'd an arduino,
How to wire it all up etc?


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## greenail

Qtron said:


> Thankyou for your reply - just asking if it is in a usable state- which it must be!
> Yes would love to try it
> is all the info avail, re how to get it into an ESP32, I have never used one, have only prog'd an arduino,
> How to wire it all up etc?



you can program them just like an arduino with the arduino IDE.  you can pick them up all over the web (amazon) for ~$5.

If you want to test create an issue here: https://github.com/jschoch/ESPels/issues and we can work through the documentation.  Right now the machine specific settings are compiled in but they can be saved in EEPROM and it would be easier to make changes, I just need a reason (like you testing) to write that code.

The configuration is:

encoder resolution setting
lead screw pitch in mm (everything is in mm but the conversion is easy)
stepper driver microstepping
wifi ssid/password


The wiring in it's simplest form is:

encoder A/B signal pins, power and ground.
stepper step/dir pins+ ground.

Once it is wired up you can go here  http://espels.s3-us-west-2.amazonaws.com/index.html and use this to connect to the esp32, or you can run it locally on your network via the source code and node.js https://github.com/jschoch/espELSfrontend.


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## Qtron

i looked at the github referred to, Jesse, It doesnt define which ESP32 to use, as far as I can tell.
There are many terms used in there & in the readme, which I dont understand. (i.e., "uses react and websockets to make awesome")
I also don't know what you mean by 'node.js', as above.
I think a lot more detail will be needed to get it going..
ESP32 choices on ebay are: [ https://www.ebay.com.au/itm/ESP-WRO...345595?hash=item343f8a92fb:g:V4AAAOSwiBhgAnrN ]
ESP-WROOM-32 ESP32U,
ESP-WROOM-32 ESP32D,
ESP32 38 Pin,
ESP32 30 pin.
pls define.
In the above reply, the ESP32 pins are not defined for the encoder signals, nor the step & dir pins - please define!
cheers,


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## greenail

you want a dual core esp32 (not esp32-s).  You don't need PSRAM so you don't need to get a wrover type, get the wroom.  There are also different names for the modules which have a U.FL antenna connector.  you may or may not need this based on your wifi signal.  I don't use one and my lathe is about 40ft from my wifi router.  here is some more info



			ESP32 Modules and Boards - ESP32 -  — ESP-IDF Programming Guide latest documentation
		


The easiest recommendation for you is to get a esp32 devkitc v4, other boards will work but this is the common reference design.

The pins depend on the board you buy but most of the pins are fully configurable.  There are plenty of available pins on the devkitc and here is a handy reference to the usable pins









						ESP32 Pinout Reference: Which GPIO pins should you use? | Random Nerd Tutorials
					

The ESP32 comes with 48 GPIOs with multiple functions. This article intends to be a simple and easy to follow reference guide for the ESP32 GPIOs.




					randomnerdtutorials.com
				




it may be easier for you to open an issue on github in the repo for us to document all this.

Regarding terms:  

"react"  *React* (also known as *React.js* or *ReactJS*) is an open-source, front end, JavaScript library[3] for building user interfaces or UI components.  It is very common and well supported.

"websockets"  While html (for web pages) is stateless, websockets is stateful and allows bidirectional communication between the espELS and the web app you use to control it.  This just boils down to it being faster and easier to use for this application.

"node.js"  is a development platform that folks use to develop javascript applications.  This is only used when developing the react user interface or to run the react webapp locally on your network.  The app can be "transpiled" into static files which I have provided a link for hosted on amazon's S3 cloud service.


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## AlanB

I was looking at a Pi Pico here and thinking it might be suitable for an ELS. Dual core, $4, 133 MHz, Hmmm. One core for UI, one for the real-time. The hardware PIOs could also be used for reading encoders and generating motor pulses, though I don't think it would be required. Might just put it on this new PM-1228. How is the ESP-32 setup doing?


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## greenail

AlanB said:


> I was looking at a Pi Pico here and thinking it might be suitable for an ELS. Dual core, $4, 133 MHz, Hmmm. One core for UI, one for the real-time. The hardware PIOs could also be used for reading encoders and generating motor pulses, though I don't think it would be required. Might just put it on this new PM-1228. How is the ESP-32 setup doing?


The ESP32 is great because the user interface can be used from a phone or tablet or PC.  You can also have different configs for different operations.  Designing a good hardware user interface is hard, development is hard, and forget about changing it without having to redo everything.  You'd have to add a wifi or bluetooth interface to the pi pico to get that benefit.


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## AlanB

I'd prefer for my lathe ELS software to be stable, and not need to be updated years later because some phone library was no longer valid. I do agree that user interfaces are hard, and I don't want something like the popular ELS that uses a $2 LED display/button board with severe limitations and lack of flexibility. Better interfaces are possible these days with a rotary encoder knob (or two) and a graphical display and in this case perhaps a dedicated switch or two (even better than a phone interface). Once it works, lay in a few spare parts and only touch it if you want to improve it. At some point it is done and no further changes are needed, and it keeps working till the hardware breaks. So while a phone interface is neat, I don't think I want one on my lathe, but that's just me. 

My 3D printers do have wireless interfaces, and that's fine because someone else is maintaining it, I don't have to hack the code every few years to keep it working. If the hackers were to get in they could overheat a heater or send a little motor past the limits, but that's hardly comparable to what they could do with a 2hp lathe ELS. Scary thought.

There are some Pico boards that have Wifi etc. Perhaps even using an ESP32. If that is needed it is best offloaded to separate processors.


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## Qtron

hiya Greenail,
Its been a while!
Hope all's well.

- certain 'political' activities where we live really threw nasty 'spanners' into the whole ELS effort here.
At one point we were not allowed to go to ANY retail shops bar for necessities, but that got killed off after a few miserable weeks.
[Full on commo stuff!!!]

Could you pls tell me whats happening w developments, any iterations, link for the code, if released yet and schematics/docs?
cheers!


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## greenail

Qtron said:


> Could you pls tell me whats happening w developments, any iterations, link for the code, if released yet and schematics/docs?
> cheers!



I use it all the time, happy to add some documentation, tell me what questions you have.

code is here: https://github.com/jschoch/ESPels and here: https://github.com/jschoch/espELSfrontend

Basically you just need to have an esp32 configure it with:  microstepping, wifi SSID, name, pin mapping, and lead screw pitch.  Then as far as hardware you need to wire up 2 pins for the encoder (ttl quadrature) and 3 pins for the stepper.  You may want to use stronger pullups for your encoder but you can use the internal pullups for the esp32.  Do you need a circuit diagram?  I have a display on it but it isn't being used and I can try to make it compile time optional if you want.


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## Qtron

excellent Greenail,
   Been a bit slow to respond, up ALL night fitting antennae to a Dell    laptop, then jumping thru a heap of driver/MS hoops to get mobile BB    connectivity 
   - it just doesn't want to co-operate!
   Weird thing is i just had the patch antennae hanging out the back end of the laptop to test, and I couldn't stop it from connecting! (despite a    strong local wifi)- now its being fiendishly rebellious.
   Anyway glad ESP32 works well, consistent! 
   Yes would love schematics & a display screen, but only if U have    time for that.
   Would be  great to see a pic of your setup too, if U wish
   I finally caught up w Clough42 vids, that $110USD servo stepper    motor from Stepperonline is a hoot. It flies!
 I've never seen a stepper at 3000 rpm with some torque left up its sleeve.
   Could U pls tell me how to save gerber files off github..   I can    see the folder, & its contents, but i cant save it..
   [Dont tell me i have to copy all such files & then zip em up to    send to JLCPCB, do I?]
   If so, how does one assoc the drill files with it, so that it all    makes sense their end? - i'm presuming, of course.
   BTW:

is this the right animal: ESP32-WROOM-32 Espressif?


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## flork

can someone advice most capable diy electric leadscrew ? im thinking about elsv2 from hobbymachinist


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## Dabbler

flork said:


> can someone advice most capable diy electric leadscrew



The rocketronics product is very mature and in over 1000 installations.


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## RJSakowski

Welcome to the forum!
What is your skill set and what tools do you have at your disposal?  There are several diy ELS builds which vary in features and in complexity.  Perhaps the simplest in terms of features is the Clough42.  It will cut a variety of predefined inch and metric threads and feed rates.  It has several possible kit options for those who don't have full machining capability and a fairly complete set of videos to walk you through the build.  

There are other ELS builds which have more features but require a better understanding of what is involved, particularly from the software side.  @greenail did a fairly comprehensive description of his build.  If I recall correctly, it has considerably more capability.  @WobblyHand  is wrapping up his design and build which also has more capability, including incorporating an integral DRO.


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## flork

im thinking about building this 



maybe someone here build it and have some opinion , i want to create most versatile els, about my tools, i have access to soldering iron, hotair, i build few 3d printers, so i think it is possible, im just dont do coding.


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## GunsOfNavarone

I like the capabilities of that one and it seems to be fully (damn near?) CNC, it does not look to be an easy build and with no help videos of the build...seems daunting. I would love to go full cnc but without losing manual control, maybe a good fit, but like you, coding and problem solving, it might be frustrating for me (I have a G0602 with the Clough ELS) I have found the limit of the stepper Clough used on the leadscrew and am a bit nervous to change to what he changed to, probably for the same limitations.


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## RJSakowski

If I were thinking of going that route, I would seriously consider going full CNC.  With a CNC lathe, you change change the functionality by simply writing G code.  CNC conversions abound and are fairly well documented.

I have the Clough42 ELS on my 602 and the only thing on my wish list was the ability to enter custom thread pitches from the UI.  That has been partially accomplished by kwackers on github who has modified the code to permit custom metric thread pitches. ( It lacks the resolution to enter  inch pitches accurately. ).

As to threading to a shoulder, I can accomplish this by virtue of my variable apeed drive which permits me to slow the lathe down to zero rpm as I approach a shoulder.  For the few times that it is required, it isn't a problem doing this manually.


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## flork

yes, but after spending some time reading, found good vid about comparistion, and its look likt its not worth spending time, for saving few $ when you can buy els v4 in basic setup, and only connect two close loop steppers


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## WobblyHand

GunsOfNavarone said:


> I like the capabilities of that one and it seems to be fully (damn near?) CNC, it does not look to be an easy build and with no help videos of the build...seems daunting. I would love to go full cnc but without losing manual control, maybe a good fit, but like you, coding and problem solving, it might be frustrating for me (I have a G0602 with the Clough ELS) I have found the limit of the stepper Clough used on the leadscrew and am a bit nervous to change to what he changed to, probably for the same limitations.


Which stepper did you use?  How many oz-in or Nm?  I have a 4Nm stepper on my G0602.  Think it is stuttering on 4 TPI threads, but I didn't give it a fair test.  The 3/4" steel work piece was deflecting due to the root of the screw being too narrow.  My stepper is connected 1:1 to the lead screw.


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## GunsOfNavarone

@WobblyHand it's been a while, but my build is EXACYLY like James' 1st go at it other than I hid all the motors/encoders and such. I know James went to a stronger motor, I just don't know if I would need to go into the code and changes steps and what not. changing a number isn't so bad, but connecting to the launch board (both physically and digitally can be a pain in the butt. Again, I bring this up because once the connection between spindle and encoder is stopped (by whatever means) you need to power down the ELS driver and launch board, then reboot.


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## RJSakowski

WobblyHand said:


> Which stepper did you use?  How many oz-in or Nm?  I have a 4Nm stepper on my G0602.  Think it is stuttering on 4 TPI threads, but I didn't give it a fair test.  The 3/4" steel work piece was deflecting due to the root of the screw being too narrow.  My stepper is connected 1:1 to the lead screw.


Consider running the gear box in the 1C configuration.  You will double your torque to the lead screw. I am using a 4.25 N-m hybrid stepper and have no problems so far.  I did measure torque output as the ability of the carriage to lift a dead weight and found that I could lift 110 lbs.  

Another thing that I discovered is that my half nuts were closing too tightly on the lead screw which required a fair amount of torque at no load.  There is an easy fix for the 602. https://www.hobby-machinist.com/threads/grizzly-g0602-half-nut-engagement.80832/#post-717716


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## GunsOfNavarone

@RJSakowski if someone were to change from 1A(?) to 1C, what changes would you have to do with the software? (I have a G0602 as well) I really want to upgrade to the stepper motor clough42 went to, but b/c of the potential of needed to go back into the software programming, I’m avoiding it for now. Honestly I’m not sure if his motor change even needed it. It’s rare I run into an issue, but I’d be lying if I said I have never done anything it couldn’t handle.


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## RJSakowski

There are several ways to handle this.  I changed my lead screw pitch from 12 tpi to 24 tpi. Alternatively, you could change the encoder pulses.


----------

