# ELS on Mini-Lathe?



## devils4ever (Jul 26, 2020)

I have a Micro Mark MicroLux 7X16 lathe and I'm trying to determine if it's worth putting on ELS. I want it because I seem to be doing a lot of threading and I'm getting tired of changing gears. But, it's a small lathe and adding ELS could be challenging. I really don't have the room for a larger lathe at the moment, but is it worth it?

Opinions?


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## RJSakowski (Jul 26, 2020)

I don';t think an ELS would be particularly challenging on a 7 x 16 lathe.  The largest component would be the stepper/servo motor.  A NEMA 23 motor frame would be appropriate.  The other mechanical components would be the encoder, pulleys, and belts.  All the change gears would be removed.

Is it worth it is another question.  Does an ELS give you any additional capability?  e.g., reference, the Clough42 ELS  It will give you forward and reverse on the lead screw, possibly a greater range of threads and feeds, Imperial and metric threads at the touch of a button, and a spindle rpm display.  

As to cost, I converted my lathe for $225, using some components on hand.  A more likely cost would be $350 to $500.  There will be a moderate amount of work required including some milling; it's not plug and play.  Your call as to is it a good value.


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## GunsOfNavarone (Jul 26, 2020)

I have a working system (Clough42) on my work table. I am waiting on a 60 tooth gear and I still need to design and CNC the 2 brackets. I know for me, adjusting seen on the fly (VFD) was worth it and the ELS will even be a better improvement. For threading it is priceless (for someone that does a lot) for me, getting the right, fine tuned, rate is going to be so nice. I say do it!


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## devils4ever (Jul 27, 2020)

I guess there's two aspects to this potential project. The first is whether it's worth putting on an ELS onto such a small lathe. So far, I haven't run into any problems with the size. I've been able to turn everything I need to. I would LOVE to be able to take bigger cuts. That's where this lathe is lacking. I see youtube videos where they are taking deep cuts on a full size lathe without issue that I could only dream of on my lathe. I would need to take 3, 4, 5 or more times as many cuts to achieve the same thing. A little more rigidity would be nice as well.

The second aspect is actually attaching this to the lathe. See pic below with a 12" rule for reference. I think mounting the stepper might be fairly straightforward, but the encoder on the main spindle looks challenging. It seems a little tight in there. I have no problems dealing with the electronics and wiring since I just finished converting my PM25 to CNC. Mounting the encoder and stepper looks more challenging. Also, I've never dealt with stepped pulleys and belts. Where to get? What size? etc.


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## macardoso (Jul 27, 2020)

I'm sure you're already aware that the thing limiting your cutting is the mass of cast iron you are missing. No matter what attachments or how big a spindle motor you add, you'll never take a cut like a larger lathe will.

So here is a thought... Take the $500 you'd spend on the ELS and put it towards a larger lathe with a quick change gearbox. Yes, you'll still need to change gears to do metric threads, but whatever. I found a used 12x36" lathe (1000lbs) for $1200. That was a decent deal, but there are lots of options out there. The lathe you have is great to learn on, but will never be a production machine.


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## devils4ever (Jul 27, 2020)

It's not so much the $$$. It's the space and access. I barely have enough room for this mini-lathe. It mounted on a plywood base with wheels which I'm constantly moving around. Plus, getting a larger lathe into my basement is tough. No outside access and stairs with a 90 degree bend halfway down.

My PM25 mill was tough to get into my basement.


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## macardoso (Jul 27, 2020)

100% agree then. I brought my 12x36 down the basement and it sucked! had to bring it down in pieces!


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## ttabbal (Jul 27, 2020)

If you are committed to sticking to the little lathe, I expect you could install an ELS on there. As for if it's worth it, it depends on how much you find yourself messing with the gears and how annoying you find that. I like the ability to thread without changes, but the biggest reason for me was easily variable feed speed. 

I went with replacing one of the gears on a stack with a GT2 pulley. So the spindle drives a normal gear, stacked with the pulley. That drives the encoder. I kept the ratios the same, so the encoder ends up 1:1 with the spindle. That's not strictly necessary, but I would suggest doing it if you can or at least using a whole number ratio. There is almost no power needed to spin the encoder, so it doesn't have to be really strong or anything. 

The servo you could mount to the bench if you had to. 

The GT2 belts and pulleys are available on Amazon. They are super common on 3D printers, so they are everywhere. They also have some of the larger ones, but I ended up ordering them direct from China on ebay. The encoder came that way as well. I think everything else had US sellers. 

One thing I would want if it were me, is power cross feed. I'm not aware of any minis with that. The smallest I've seen with that is the PM1022. But if you're really tight for space, it might not work for you. There are a few mods that might help with rigidity, like replacing with compound with a solid block. But overall, your limit for cut depth is mostly down to the size of the machine. I have a PM1127 and have a similar issue there. I just figure it's a hobby, so I don't mind a few extra passes. I can't make a 4" deep cut like Abom, but I don't really need to either.


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## RJSakowski (Jul 27, 2020)

devils4ever said:


> I guess there's two aspects to this potential project. The first is whether it's worth putting on an ELS onto such a small lathe. So far, I haven't run into any problems with the size. I've been able to turn everything I need to. I would LOVE to be able to take bigger cuts. That's where this lathe is lacking. I see youtube videos where they are taking deep cuts on a full size lathe without issue that I could only dream of on my lathe. I would need to take 3, 4, 5 or more times as many cuts to achieve the same thing. A little more rigidity would be nice as well.
> 
> The second aspect is actually attaching this to the lathe. See pic below with a 12" rule for reference. I think mounting the stepper might be fairly straightforward, but the encoder on the main spindle looks challenging. It seems a little tight in there. I have no problems dealing with the electronics and wiring since I just finished converting my PM25 to CNC. Mounting the encoder and stepper looks more challenging. Also, I've never dealt with stepped pulleys and belts. Where to get? What size? etc.
> 
> View attachment 331605



If I were converting your lathe to an ELS, I would remove all the gears and the reversing banjo mechanism.  Ideally, I would replace the spindle gear with a gear belt pulley driving another gearbelt pulley on the encoder shaft, located toward the front of  or below the spindle.  The stepper motor would be either have a gearbelt pulley driving a second pulley mounted on the lead screw shaft.  This arrangement wold be oriented horizontaslly at the bottom of the lathe.


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## devils4ever (Jul 27, 2020)

Yeah, this is a tough decision. Having more space and basement access would have me sell this lathe and go for a bigger one. If nothing else, I'd get more rigidity and mass.

I'm not familiar with GT2 belts and pulleys. Are there any that would fit the main spindle gear? The pulley's ID would have to be matched to the spindle's OD. It looks like a set of special wrenches are needed to remove the current setup. I'm not as concerned with the lead screw shaft since it's a lot smaller.


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## macardoso (Jul 27, 2020)

devils4ever said:


> Yeah, this is a tough decision. Having more space and basement access would have me sell this lathe and go for a bigger one. If nothing else, I'd get more rigidity and mass.
> 
> I'm not familiar with GT2 belts and pulleys. Are there any that would fit the main spindle gear? The pulley's ID would have to be matched to the spindle's OD. It looks like a set of special wrenches are needed to remove the current setup. I'm not as concerned with the lead screw shaft since it's a lot smaller.



Good thing you have a lathe to machine those pulley hubs 

GT2 is a small pitch curvillinear profile pulley. They are good to about 2HP and have lower running noise than most belts. Fabric faced belts add to the noise reduction.

You could probably get a 10" lathe down to the basement without too much hassle. The headstock can be removed to save weight.


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## ttabbal (Jul 27, 2020)

I wouldn't mess with the spindle directly. Those nuts probably set the preload on the main bearings. I doubt you could purchase one to fit directly anyway, and it's tough to measure and such without taking it apart.


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## devils4ever (Jul 27, 2020)

ttabbal said:


> I wouldn't mess with the spindle directly. Those nuts probably set the preload on the main bearings. I doubt you could purchase one to fit directly anyway, and it's tough to measure and such without taking it apart.



You may be right, it's hard to tell looking at it. It would be nice to remove all the gears though. Lots more space to mount the encoder and stepper.

I could possibly mount the encoder on the first change gear (small one above large 80T gear).


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## GunsOfNavarone (Jul 27, 2020)

devils4ever said:


> Yeah, this is a tough decision. Having more space and basement access would have me sell this lathe and go for a bigger one. If nothing else, I'd get more rigidity and mass.
> 
> I'm not familiar with GT2 belts and pulleys. Are there any that would fit the main spindle gear? The pulley's ID would have to be matched to the spindle's OD. It looks like a set of special wrenches are needed to remove the current setup. I'm not as concerned with the lead screw shaft since it's a lot smaller.


With the lathe you have....you could make about any pulley fit!   If it currently has a 60 tooth, you be looking at a pulley only i dunno, 1.25" in diameter. WHat's the diameter of your spindle on the geared side? But if you had to go bigger for hole side of the spindle, the gear you choose on the stepper side could bring rpm's back to where you need it. The more the convo progresses, the more I feel like it may not be worth it.


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## devils4ever (Jul 28, 2020)

The main spindle diameter is about 1.040" measured at the end which is threaded. I can't measure the shaft diameter without taking off the nuts and gear.

_"The more the convo progresses, the more I feel like it may not be worth it."_
I'm not sure I get what you mean with this statement.

I was thinking of leaving the 3 gear train as is and attach the encoder directly to the shaft shown below. It should be easy to mount the encoder there since there is a mounting bracket for the gear shaft.

I started pricing things out and I was shocked to see the encoder costs over $400 from US sources. eBay and other importers are much less.


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## macardoso (Jul 28, 2020)

There is a huge variation in encoders with resolution, data format, packaging, and durability. You need a low count encoder with small packaging and durability.

Here is a mid price one from a US company.



			https://www.automationdirect.com/adc/shopping/catalog/sensors_-z-_encoders/rotary_encoders/light_duty_incremental_encoders_(quadrature)/6mm_solid_shaft_npn_open_collector_(trd-s_series)/trd-s1024ad
		


And a $20 import one from eBay:









						NEW Incremental Rotary Encoder 1000p/r 6mm Shaft 5-24vdc  | eBay
					

Shaft: 6mm Dia, 13mm Length.



					www.ebay.com


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## matthewsx (Jul 28, 2020)

I feel like you already know the answer to the second question. This is definitely one of those "just because you can doesn't mean you should" situations. 

Find a better lathe and if you have to hire someone to get it into the basement, and move out some other stuff, it will still be better than trying to improve what you have there. If you really only have that much room to work with, and want to go ahead with this project why not just make it full CNC? It wouldn't cost much more or be that much harder.

FWIW when I put out a call for help on moving a lathe on this forum I got two very competent volunteers right away and now I have absolutely the largest lathe that will fit into the available space

Where there's a will....


John


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## vtcnc (Jul 29, 2020)

ttabbal said:


> I can't make a 4" deep cut like Abom, but I don't really need to either.



Ok admit it...if you could, you would, right!?


Sent from my iPhone using Tapatalk


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## devils4ever (Jul 29, 2020)

I guess the other option is to go ahead with ELS conversion on this lathe and if I decide to get a larger one, remove it and put back all the old hardware to sell. I would think 99% of the project would work on a larger lathe.

I do have a wood lathe taking up a lot of space that I don't use that much. Hmmm.


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## RJSakowski (Jul 29, 2020)

devils4ever said:


> The main spindle diameter is about 1.040" measured at the end which is threaded. I can't measure the shaft diameter without taking off the nuts and gear.
> 
> _"The more the convo progresses, the more I feel like it may not be worth it."_
> I'm not sure I get what you mean with this statement.
> ...


I bought my Omron encoder on eBay for $21.03.  https://www.ebay.com/itm/152211269839


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## RJSakowski (Jul 29, 2020)

FWIW, Here is my cost for materials for the Clough42 ELS build.



Edit: not included are switches, connectors, and wiring, all of which I had on hand.


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## ttabbal (Jul 29, 2020)

vtcnc said:


> Ok admit it...if you could, you would, right!?



Oh sure! I would love to have one of those huge machines that could. I suspect the wife would use me to fertilize the garden though.


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## devils4ever (Aug 1, 2020)

Well, I decided to go ahead with the ELS conversion on my mini-lathe.

I started ordering parts going with the electronics first and doing the mechanical last to keep the lathe usable as long as possible. This was the same thing I did for my mill CNC conversion.


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## Ken from ontario (Aug 2, 2020)

devils4ever said:


> Well, I decided to go ahead with the ELS conversion on my mini-lathe.
> 
> I started ordering parts going with the electronics first and doing the mechanical last to keep the lathe usable as long as possible. This was the same thing I did for my mill CNC conversion.


I'm glad you have decided to go ahead with your plan, I hope you take step by step pictures and share them with us.


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## devils4ever (Aug 2, 2020)

I'll try. I've generated a part list and started ordering parts. It will definitely be a journey, but it should be a lot easier than my CNC conversion on my mill.


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## devils4ever (Aug 2, 2020)

Okay, I got some questions already. I'm not sure if I should ask them here or join the large ELS thread. But, here goes!

In any case, I downloaded the latest version of Code Composer Studio, V 10.1.0. When it came to debug options, it didn't list the option Clough42 selected (TI XDS Debug Probe Support). After reading some comments on his video (Part 10), I decided to go back to V 9.1.0. Is this correct?

Next, I wasn't sure which version of the ELS project I should download from github. Clough42 used V 1.0.03. I downloaded V 1.1.02. Is this correct?


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## RJSakowski (Aug 2, 2020)

I used v. 9.1.0 but that was back in December.  I loaded v. 1.0.03 of the Clough42 firmware.  Everything works for me.


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## devils4ever (Aug 2, 2020)

I *think* version 1.1.02 works with V2 of the interface PCB which I ordered from Clough42 on eBay.


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## devils4ever (Aug 4, 2020)

So, I have some more questions on setting up Clough42's ELS. I'm wondering if I should:

continue here
 join/add to the massive ELS thread here
create a new thread dedicated to Clough42's ELS
Thoughts?


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## ttabbal (Aug 4, 2020)

I would say if the questions are about your particular application/machine, a new thread with the machine in the title. This thread is probably fine as well. If it's a common one to the ELS setup that others would run into, it might make sense to use a common thread like the big ELS thread. 

We aren't too picky around here usually.


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## devils4ever (Aug 4, 2020)

Okay, I'll fire away here then.

The servo motor drive has 3 inputs from Clough42's interface PCB. Namely, STEP, DIRECTION, and ENABLE. The signals going to the the drive are differential. Typically, the "+" inputs are tied to +5V and the STEP, DIRECTION, and ENABLE pins from the interface PCB are connected to the '-' inputs. So, that would make all of them active low. Yet, in the code, there are defines for these that are set as follows:
// #define INVERT_STEP_PIN true
// #define INVERT_DIRECTION_PIN true
#define INVERT_ENABLE_PIN true

This implies the ENABLE pin is active low (as it should be), but the STEP and DIRECTION pins are active high. Isn't this wrong?


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## ttabbal (Aug 4, 2020)

The code in the repository should match up with this wiring diagram. 

https://raw.githubusercontent.com/clough42/electronic-leadscrew/master/docs/images/WiringDiagram.JPG

It looks like it's wired for active low, however, direction at least can go either way depending on which way you want the motor to turn with you have the control panel set for "FWD". Step I'm not sure on, but it did work fine for me that way. You can change those to adjust to your setup.


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## devils4ever (Aug 5, 2020)

Okay, here's my next question. I plan on running the encoder directly coupled to the geared main spindle. See photo in post #15 and red circled shaft. So, I don't need any pulleys for this. I'm designing a mount for this now.

I'm looking at getting pulleys for the lead screw. Clouth42 uses a 3:1 ratio and I'm planning on using the same hybrid stepper motor. I'm assuming this will give me good performance (torque and speed) since my lathe is smaller than his. So, do I order HTD 3M pulleys and belts? Any recommended vendors?


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## ttabbal (Aug 5, 2020)

By directly coupled, I assume you mean a hard coupling or similar? There's nothing wrong with that, but you need to know the gear ratio to that point so your ELS knows how much the spindle moved. You can just count the teeth and calculate the ratio, then use that to calculate the pulse count for the encoder in the code. 

I used HTD5M, but I doubt you would have any trouble with the smaller 3M belts, and they would probably fit better on the mini lathe. I bought from these ebay vendors, shipping from China is always a bit slow, but it works. Amazon had a couple of people selling parts, but the variety wasn't very good. I just ordered a variety of belt sizes and used the one that best fit. 

https://www.ebay.com/usr/rubberbeltsonline




__





						eBay Profile - error
					





					www.ebay.com


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## devils4ever (Aug 5, 2020)

ttabbal said:


> By directly coupled, I assume you mean a hard coupling or similar? There's nothing wrong with that, but you need to know the gear ratio to that point so your ELS knows how much the spindle moved. You can just count the teeth and calculate the ratio, then use that to calculate the pulse count for the encoder in the code.
> 
> Yes, I plan on mounting the encoder with the shafts facing each other and in line with a simple coupler machined for each shaft diameters. I think the gear ratio is 1:1, but I'll double check.
> 
> ...


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## devils4ever (Aug 6, 2020)

Another question. This time on the encoder. 

The Omron encoder has outputs labelled: A, B, and Z. The TI LaunchPad Evaluation Board has a header for encoders and they are labelled: 1A, 1B, and 1I. I'm assuming A goes to 1A and B goes to 1B, but does Z go to 1I? From the Omron datasheet, it's hard to tell what Z does. Is it 1 pulse per revolution?


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## kb58 (Aug 6, 2020)

I remember wondering the same and hooked it up as you guessed, and it worked fine.


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## devils4ever (Aug 6, 2020)

Here's some drawings of what I'm thinking for mounting the encoder.


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## devils4ever (Aug 17, 2020)

I have the same enclosure that Clough42 used. It's a Hammond CHKO18126. I'm about to start mounting the components in it. However, the sheet metal is 16 gauge thick. Is this thick enough to drill and tap? Or, do I need to drill straight through and use a nut and washer? I don't have much experience with sheet metal. Thanks!


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## RJSakowski (Aug 17, 2020)

devils4ever said:


> I have the same enclosure that Clough42 used. It's a Hammond CHKO18126. I'm about to start mounting the components in it. However, the sheet metal is 16 gauge thick. Is this thick enough to drill and tap? Or, do I need to drill straight through and use a nut and washer? I don't have much experience with sheet metal. Thanks!



16G.  is .06" thick.  I would use sheet metal screws , a threaded insert, or nut and washer; your choice.


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## ttabbal (Aug 17, 2020)

I used nut and washer. It holds well and is easy to set up.


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## devils4ever (Aug 17, 2020)

Got it. Thanks.

Next, question. I'm thinking the best way to make cutouts in the sheet steel is to use an angle grinder. Make sense?


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## ttabbal (Aug 17, 2020)

Cutoff wheel on an angle grinder or dremmel would work. I used a hole saw for the large cutout, twist drills for the mounting holes. I just happened to have a hole saw that was about the right size.


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## devils4ever (Aug 24, 2020)

Okay, making progress. I used an angle grinder with cutoff wheel to cut the openings. First time using one. The first cutout (power entry) was challenging, but came out okay. The second one (main panel) was much better. I had to use the grinding wheel to remove some of the box's knockouts. I also used a Dremel tool to fine tune the openings and remove the sharp edges. I think a die grinder (which I don't have) would have been better.

Overall, I'm pleased and now it's on to mounting all the components inside.


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## devils4ever (Aug 25, 2020)

More progress. I have everything mounted. I'm waiting on some heat shrink tubing to finalize the wiring, but I have enough wired to do some basic testing. I programmed the TI LaunchPad eval board as follows:
LEADSCREW_TPI = 16
STEPPER_MICROSTEPS = 3
STEPPER_RESOLUTION = 1000

I plan on using a 3:1 reduction on the motor pulleys hence the STEPPER_MICROSTEPS set to 3.

After powering up everything, I set the display to 16 TPI and turn the rotary encoder one time and expect to see 3 turns of the motor. I don't. So, I use the calibration cable from Automation Technologies along with their ESDSeries software and see that the motor is set to 4000 pulses/rev. I set it to 1000 and download it, but it doesn't seem to stay. I try using the save button and now I think it's sticking. There's a setting for the motor encoder that's set to 4000, but I don't think I need to change this since this is only internal the motor and drive, correct?

Anyways, I think I'm getting 3 turns of the motor for every turn of the rotary encoder.

Starting to think about mounting the rotary encoder and motor on the lathe and I'm still waiting for the pulleys and belt from China.


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## ttabbal (Aug 25, 2020)

Nice work on the panel! I'm not sure about the stepper controller. I didn't have to mess with it, but it sounds like you have it working as needed. The real test is threading so you can compare to a pitch gauge. Waiting for the belts and pulleys can be annoying. Always takes longer than you want it to.


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## devils4ever (Aug 27, 2020)

Panel is done except I might clean up the wiring a little bit more.

Onto the rotary encoder mounting hardware.


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## devils4ever (Sep 2, 2020)

I got my pulleys and I'm looking at options to put the keyway into the lead screw pulley. It's 3 mm wide. At first, I was thinking of using a 3 mm end mill and square off the corners with a file. However, the longest 3 mm end mill I could find is only about 1/2" and I need 1".

A broach would work, but I don't have one and I don't have an arbor press. I wouldn't mind getting an arbor press since I think it would be very useful. In the interim, can a broach be used with light taps from a hammer? Or, using a vise? The pulley is Aluminum.

Another option is using the lathe with a boring bar. I'm not sure I like this idea since it's only a mini-lathe and I'm not sure how successful this would be with flex and all.


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## Firstram (Sep 2, 2020)

I've broached aluminum pulleys on my mini lathe, take small bites, it works fine.


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## ttabbal (Sep 2, 2020)

I wouldn't try to hammer a broach. They are hardened and might break. 

The pulley is aluminum and pretty easy to work. I used a small HSS bit in the lathe using the carriage as the press. You can get a little pack of HSS bits at Harbor Freight. They aren't great, but they are good enough for this if you don't have any little ones. I just used it directly, but it works better if you grind a little relief. There are a bunch of youtube videos showing how to do it. 

There's always the small files as well.


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## devils4ever (Sep 3, 2020)

Another slight snag. I have the rotary encoder mounted on the main spindle, but I'm seeing a slight wobble in it as it turns. I had a feeling this would be an issue. I made a solid coupler, but I think I'm going to need a flexible shaft coupler of some type.


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## devils4ever (Sep 5, 2020)

I solved my issue with cutting the keyway for the pulley. I researched this a bit and decided to use the lathe to cut the keyway. At first, I thought I'd use a HSS bit, but I didn't have any 3 mm tooling over 1" long. So, I thought about using a 3 mm broach on the lathe. So, I ordered it from McMaster-Carr along with the appropriate 12 mm bore bushing. Not cheap!

Well, things started okay. I was able to use the tailstock with the Jacobs chuck to push the broach about half in before it didn't seem to want to go any further. I also tried the carriage, but it didn't want to move at all. Remember this is a 7X16 mini-lathe.

I decided to try using my huge woodworking vise. It worked beautifully! It had plenty of force to push the broach through. I used the lathe's 3-jaw chuck to hold the pulley. Near the end of the stroke, I used a 2X6 with a hole drilled in it to allow the broach to exit and not hit the vise's jaw. I know this is not the approved method and most machinist's would shudder, but it worked. It took a 10 second operation on an arbor press and made it into a 30-40 minute adventure! If I need to do this again, I will buy an arbor press!


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## kb58 (Sep 5, 2020)

I made my keyway by first drilling two small holes on-center in the corners, then using a 1/8" end mill to connect them. The reasoning is that the corners serve no purpose so are "expendable."


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## kb58 (Sep 5, 2020)

devils4ever said:


> Another slight snag. I have the rotary encoder mounted on the main spindle, but I'm seeing a slight wobble in it as it turns. I had a feeling this would be an issue. I made a solid coupler, but I think I'm going to need a flexible shaft coupler of some type.
> 
> View attachment 335673


If you're going to keep the hard connection, a better way is to have the encoder free-floating on the shaft, and having the only connection to it being a radial.connection to keep it from spinning.  Direct connections on spinning things never work for long.

[edit] I don't know why I didn't suggest one of the couplers, as suggested below, sigh. I would, however, suggest the helical-cut type instead of a plastic insert, though with so little needed torque, it probably doesn't matter.


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## devils4ever (Sep 5, 2020)

kb58 said:


> I made my keyway by first drilling two small holes on-center in the corners, then using a 1/8" end mill to connect them. The reasoning is that the corners serve no purpose so are "expendable."



I thought of doing that, but the pulley is 1" thick. I'm not sure a drill or end mill would stay true if I could find one that long.


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## GunsOfNavarone (Sep 6, 2020)

What about something like...U-joint


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## devils4ever (Sep 7, 2020)

I got the wobble out using this flexible shaft coupler from McMaster-Carr. It allows for angular and parallel shaft misalignment. Each piece is ordered separately, so I was able to get a 6 mm shaft diameter and a 12 mm shaft diameter. The center piece hub comes in different durometers for different applications. Not the cheapest solution, but probably the most precise.




Here it is all mounted together.


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## GunsOfNavarone (Sep 7, 2020)

Weird, a coupler like that is the first/go to solution. I really didn't think it would allow for wobble. I assumed something was slightly misaligned? Nice!


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## devils4ever (Sep 9, 2020)

Getting close to the finish line! I have the motor mounted. I made a slot in the two mounting points to allow belt tightening adjustments.

I need to do some test cuts, but it seems to work as expected. I still need to mount the steel electronics enclosure and LED display/switch box.

The second photo below show a plywood prototype I used to test my dimensions. Note this is the second iteration of the mount. The first one had a mounting standoff in way of the belt so I had to angle the motor mounting points.


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## GunsOfNavarone (Sep 9, 2020)

I'm working hard to stash everything where it can't be seen...not a lot of room on the lathe to do that. Hopefully in the next week the motor and servo will have their homes and I'm running.


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## devils4ever (Sep 10, 2020)

I did a few test cuts and everything seems to be working. I tried different feed rates and cut a 1/2-13 thread in Aluminum. A 1/2-13 nut fit on there fine so I must have got the parameters correct in the software.

I'm still trying to determine where to mount the LED display/switch box and how to cover the encoder and motor/pulleys. I might hack up the the old plastic cover since a replacement is only $21 from LMS.


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## ttabbal (Sep 10, 2020)

Nice! My motor sticks out the side through a hole I made with a hole saw. Nothing fancy, but it gets the job done.


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## devils4ever (Sep 10, 2020)

Awesome! I just cut a metric thread on my mini-lathe. I'm really starting to like this ELS from Clough42. I'm able to change the feed rate on the fly to get the best finish. Just push a few buttons!

Same for threading. I could never cut a metric thread on this lathe, but here it is! The pic shows a M8 X 1.25 thread I cut on a piece of Aluminum stock. I know you can't tell, but that's a M8 nut on it. 

It does take some adjusting to cutting metric threads. For one, since the lead screw is Imperial, you have to leave the half-nut engaged at all times and reverse the lathe to get back to the start. I did see some tricks by oxtoolco to disengage the half-nut, but it boils down to the same thing. You need to stay in lead screw at the same point.

Also, I had to convert the major diameter and pitch diameters to Imperial since my mic and thread mic are not metric. Also, I had to convert the metric pitch of 1.25 mm to 20.32 TPI so I knew which anvils to put in the thread mic.

But, minor inconveniences to be able to cut metric threads (and Imperial) without messing with a bunch of gears!


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## GunsOfNavarone (Sep 10, 2020)

I'm doing everything I can to make sure everything fits under the hood. Why? I don't know, probably because I have a small 12x12" working area to the left of my lathe I don't want to lose. Anyway, I made a CNC bracket and the stepper motor now live under the center of the head casting. I am a little stuck on the encoder as it mounts with pulley in/ motor side out, just feels a bit ackward. I'm hoping in another week or so Had to ge a new belt for the new location since I didn't go Clough's route on mounting. I'm a bit surprised he never changed his positions as he said in the video they were temp. I mean that NOGA mag mount for the encoder. That's a shortcut for someone like me...not him.


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## devils4ever (Sep 12, 2020)

I'm completely done with this project. Hurray!

I hacked up the cover to accommodate the motor and rotary encoder. It's not the neatest job, but it works. I used my Dremel on the squarish motor opening and my boring head to cut the circular opening for the rotary encoder. I really wanted to cover the pulleys and belt which this accomplishes. I thought the pulley would be rubbing on the back (front?) of the case, but it seems to clear it.

I mounted the LED display/switch box on the wood stand facing up. Not my ideal choice because of chips landing on it, but I couldn't figure out a better spot. I covered it was plastic wrap to keep the chips at bay. This is the same think I did for my keyboard on my CNC mill. It's not elegant, but it works!

Onto another project!!!


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## Boswell (Sep 12, 2020)

devils4ever said:


> I'm completely done with this project.


Awesome !    I love the feeling when I can say a project is completely finished.


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## GunsOfNavarone (Sep 17, 2020)

The last step I have is to mount the encoder...I am seeing that wobble you speak of @devils4ever  It looks like the grub screw that tightens the gt2 pulley to encoder shaft is the culprit. It seems to pull it slightly off center when tightened. Though I'm not direct mounting, this problem still exists. TBH I find it in the pulley for stepper as well. I would like to mount it like @kb58 suggested, free floating. Unfortunately, every design I can come up with is too complicated. This isn't the space shuttle. Could someone make one and send it to me? I'll be napping on the couch  
That lazy magnetic one of Clough's is starting to look more appealing!


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## devils4ever (Sep 18, 2020)

Are you using pulleys for both the rotary encoder and the stepper motor? If so, I wouldn't think you would see any wobble. I only saw it on the encoder when it was directly mounted.


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## devils4ever (Sep 18, 2020)

I cut a 1/2-13 thread in 1018 steel to see how the ELS would do. I figured this would be a harder test than Aluminum. Plus, 13 TPI is making the motor spin much faster. I *really *like the ability to adjust the feed rate when cutting down to major diameter to get the best finish. I can start faster and then when nearing the end of the cut, I can slow down. For the final passes, I can really slow down the feed rate (to 0.001") to get a nice finish.

And when cutting the thread, push a few buttons. No more gears!


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## MrCrankyface (Sep 18, 2020)

I've been contemplating getting the ELS for my BL-250G lathe and I have to say, this thread does make a very convincing argument for it.   
Great job on the installation, looks really neat.


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## GunsOfNavarone (Sep 18, 2020)

I am using a pulley on all parts. It’s not much but I can see it in belt tension varying when rotating.


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## GunsOfNavarone (Sep 18, 2020)

I guess this is a good place to ask this question.
I had to extend the wires for the stepper, and it DID NOT like it. It would try to turn the stepper then a red light (over current) On driver would flash & stepper was out. I’m sure about everyone had to be tend those 12-18” wires from stepper...anyone experience this?


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## devils4ever (Sep 19, 2020)

GunsOfNavarone said:


> I guess this is a good place to ask this question.
> I had to extend the wires for the stepper, and it DID NOT like it. It would try to turn the stepper then a red light (over current) On driver would flash & stepper was out. I’m sure about everyone had to be tend those 12-18” wires from stepper...anyone experience this?



I looked at my stepper wiring and they are at least 2' long. 12+" outside the enclosure and 12+" inside. You may have another issue. Measure the resistance between the 3 phases with an meter. They should all be about the same.

Also, check the encoder wiring. Maybe there's an issue there. Make sure you use the extension cable provided. It must be used.

Lastly, there's a serial port on the driver that can be used to configure it. I'm not sure but there may be diagnostics there that can tell you why there's a fault.


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## GunsOfNavarone (Sep 19, 2020)

What's odd is, I removed the extension cable from stepper and problem gone. I do have a VFD on my lathe which has the extreme possibility of putting off a lot of noise. (though I do have 2 kinds of filtering going on) I "get to" spend some time this weekend dinkering around with it. What I KNOW is the problem comes from patching in some cable to the stepper. Green, brown and black..no chance I've wired them wrong. I'd route a different way but either way it will pass right up against the VFD motor and or extend the cables further. Fun!


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## GunsOfNavarone (Sep 19, 2020)

Ok, got it somewhat sorted out. The stepper came with a RS232 extension/patch cord. THAT'S the culprit. I wouldn't have guessed, seems like if it came with that, I'd be safe to use it? Anyway, it's purpose must not be so much for extending is rerouting the wires internally. OK, well I need to extend that cable as well, anyone know of an easy way? is there an extension that doesn't shift the wiring about?
Someone/somewhere suggested this as a problem. I don't think it was here, but where ever you are....you are correct!


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## ttabbal (Sep 19, 2020)

Error on Stepper Driver and no motor movement · Issue #27 · clough42/electronic-leadscrew
					

Greetings all. I've got my rig set up to test, I have the Launchpad XL, James' interface board, and the Hybrid Stepper and controller he recommends KL-23N-1000 and KL-5080H, OMRON Encoder E...




					github.com
				




Yes, you need that cable. I don't know why they did it that way, but it is what it is. The link has the pinout so you can adapt it if needed. I think the PDF for the driver has it as well. I actually cut it down, 6ft was more than I needed. I was putting the aviation connectors in anyway, so I just cut some out there. The 3 drive wires I extended using some of the cable the motor vendor sells. It's nothing special though, about any 3 wire cable would work. 

To extend the servo encoder wire, you might be able to use an old serial cable. You would have to compare the pinouts. At worst, the wire would work if you cut the ends off and installed new DB9 connectors. 

If you are getting interference from a VFD, you might try running the control cables away from it as much as possible. Avoid running parallel, cross at 90 degrees as much as possible. I haven't had problems with the VFD, but I don't have the wiring close to it and shorter wires help as well.


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## GunsOfNavarone (Sep 19, 2020)

Wow! Though that problem only existed a day before I got to the issue,it was a bit un-nerving. Thanks for the link! @ttabbal I wonder what that cable's purpose is? If nothing I need, perhaps I'll canabalize it for some fittings. I would LOVE to get this project done and outta here, but the devil is in the details...


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## devils4ever (Sep 19, 2020)

You can get a straight DB15 cable from Digikey if you need to extend that cable.


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## ttabbal (Sep 19, 2020)

I suspect the cable is just to adapt the pinout. They probably had one side already and it was cheaper to include a cable than to make a new motor or controller.


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## GunsOfNavarone (Sep 19, 2020)

The DB15 connector...its for the servo so just a signal cable. Can I use 24g? its 5 strand wire. I honestly don't know what it uses, but when I looked inside plug to see how it IS wired, it looked about that thin....I might just patch in 6" and be done with this. I really cant find any short cables, they all seem to be 3 or more feet long.


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## ttabbal (Sep 19, 2020)

It's pretty thin, almost no current is needed. It's just the sensor on the servo. So I expect 24g would be fine. I doubt you would find a 6" cable. You could probably cut a chunk out of an old serial or parallel cable.


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## devils4ever (Sep 20, 2020)

Agree. 24 gauge is fine for small current applications like this.


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## GunsOfNavarone (Sep 20, 2020)

I didn't want to cut the the servo's cable and I don't know if that "extension" has SOME purpose for testing /trouble shooting down the road, so I figured I just go ahead and buy one. Digikey? Forget it. Impossible to find anything there (though I'm pretty sure they have everything) I searched the internet for a couple hours. Under 15 pin, VGA cables really just come up. Under serial, just DB9 come up. What's a straight through and what's not? I don't know. There actually was a comment in Amazon for a VGA that actually changed the pin through. I will just have to add some length.
Crazy how difficult (impossible) it is to find a 15pin (de15?) straight though, of any length....
Thanks for the help though everyone, I'm glad this ended up being nothing.


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## GunsOfNavarone (Oct 4, 2020)

A question for whomever know the answer. I did some design changes to keep everything under the hood. The issue I'm sure that will come up, the encoder will be on the right side of it's pulley, rather than the left side of the pulley as Clough has. My encoder will be turning the opposite way now. Does anyone know what I will need to change so this will be correct when running forward versus revers? That is, when I cutting in forward direction, the carriage should move towards the chuck. If my encoder is reversed, I would assume this will be backwards unless I changes something?
This is just a mock up obviously...


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## ttabbal (Oct 4, 2020)

I'm not sure if the carriage will move reverse, but my guess is that it will. But that's easy enough to change in the code if you need to. There might already be a configuration option for it in there.


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## devils4ever (Oct 4, 2020)

Edit the configuration.h file and change the line that says INVERT_DIRECTION_PIN. Either comment or uncomment this line. Recompile and download again.


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## GunsOfNavarone (Oct 4, 2020)

Can't you change direction of stepper via the switches on the driver? I'm trying to find the "manual" for the Kl-5056(?), but not sure if it actually has one.


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## RJSakowski (Oct 4, 2020)

I have a different driver/stepper than Clough used but my driver has a switch assignment table on the cover.  Mine has a motor direction switch.


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## GunsOfNavarone (Oct 4, 2020)

Yeah, I need to do more checks on forward and reverse, but in forward mode, the carriage moves away from the chuck. I have the encoder bearing and final belt size on the way so Tuesday I'll see what all issues I need to check off.
Thanks for ideas everyone.


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## GunsOfNavarone (Oct 6, 2020)

So I did get things a bit more setup for better tests. The stepper is moving in the wrong direction because of flipping the encoder mounting direction. The easiest would be if the stepper driver has direction control on one of it switches, if not, I will have to edit that line in the configuration file as @devils4ever suggested. I'm looking forward to this project being behind me. 
I pressed a bearing in for the encoder shaft to ride on....no reason I should have to remake that bracket in aluminum....agreed? I post a picture later on.


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## devils4ever (Oct 6, 2020)

I didn't even bother switching in my case since I was able to switch the encoder direction right on the lathe with a lever.

If you are using the KL-5080H like me, there are no switches to change direction. However, you can use the serial port and their software to configure it.

But, it's simple to do in the code. You already compiled and downloaded it once, correct?


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## GunsOfNavarone (Oct 6, 2020)

So here's the deal, it seems the Ti software doesn't want to open the edited files. Almost as if they are already open (somewhere, I don't see them) and it doesn't see any changes. When I try to debug/upload, it doesn't see changes and gives some error message. I am uploading the latest version hoping that clears the cache (?) and opens the code files so I can upload. Doing everything as I did originally which was crazy easy, this time it almost seems to not want to do the same thing again even though I have doubled checked that the config file DOES have the removal of the " //" so the invert direction should work.


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## devils4ever (Oct 6, 2020)

I had to use an older version of the TI software. I'm using Code Composer Studio 9.1.0. Same for Clough42's code. I used 1.1.02.


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## GunsOfNavarone (Oct 6, 2020)

It won't let me hit select all, it won't let me check them either. This is using code composer 9 and 10


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## devils4ever (Oct 6, 2020)

Hmm. I don't know. Try rebooting?


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## GunsOfNavarone (Oct 6, 2020)

There were duplicate files so bring in new ones that had same name...issues. Fixed that, but now when it gets to "ice pick" running, I immediately get this message.


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## GunsOfNavarone (Oct 6, 2020)

Dear LORD! What a day. LITERALLY 6 HOURS monkeying with that. and LITERALLY every problem possible... it happened to me.
I could share, but it will be TLDR. I have one outcome question for you all;
If I have the controller in reverse, everything moves towards chuck....I assume that is the opposite for everyone else? With the forward/reverse button, I can get both directions, it just seems backwards. Perhaps its one of the other lines of code? 
Anyone know what
Invert step pin is?
invert enable pin?
This is my line 71 through 74
71// #define INVERT_STEP_PIN true
72#define INVERT_DIRECTION_PIN true
73#define INVERT_ENABLE_PIN true
74#define INVERT_ALARM_PIN true
Being the stepper motor and the encoder are backwards versus Clough, I might need 2 items commented/uncommented? Maybe they cancel each out but would still be reversed? I feel like there is a time/space continuum thing going on here.


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## ttabbal (Oct 6, 2020)

The invert settings just set it up for high or low level for logic signals. I believe all you should have to do is set INVERT_DIRECTION_PIN false and it should switch the direction of the stepper driver. I'm 90% sure "FWD" on the controller and FWD on the lathe send the carriage toward the chuck. I'll check next time I'm in the shop.


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## GunsOfNavarone (Oct 6, 2020)

OK...it's all good now. I hate computers....


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## GunsOfNavarone (Oct 13, 2020)

Well, ran the first test as everything is in, mounted and polished. The problem I'm having must have something todo with the config.H file. I ran 8 TPI and the score marks are pretty much touching each other, looks more like a rough finish pass than threading. Here my config settings (keeping in mind I have the same lathe as Clough and the exact same encoder/stepper-servo.)
Thoughts?

#ifndef __CONFIGURATION_H
#define __CONFIGURATION_H




//================================================================================
//                                  LEADSCREW
//
// Define the type and pitch of leadscrew you have in your lathe.  If you have an
// imperial leadscrew, define LEADSCREW_TPI.  If you have a metric leadscrew,
// define LEADSCREW_HMM (pitch in hundredths of a millimeter).  Do not define
// both.
//================================================================================

// For Imperial leadscrews: pitch in Threads Per Inch (TPI)
#define LEADSCREW_TPI 12

// For metric leadscrews: pitch in hundredths of a millimeter (HMM)
// Example: 200hmm = 2mm
//#define LEADSCREW_HMM 200




//================================================================================
//                                STEPPER/SERVO
//
// Define the number of steps and microsteps for your stepper motor, the pin
// polarity of the driver, and whether to use additional features, like servo
// alarm feedback.
//
// NOTE: If you are using a servo drive with something other than a 1:1 drive
// ratio, you can use the STEPPER_MICROSTEPS to compensate.  For example, if you
// have a servo configured for 1000 steps/revolution and it drives the leadscrew
// through a 3:1 reduction, you can set STEPPER_RESOLUTION to 1000 and
// STEPPER_MICROSTEPS to 3.
//================================================================================

// Steps and microsteps
#define STEPPER_MICROSTEPS 1
#define STEPPER_RESOLUTION 1000

// Step, direction and enable pins are normally active-high
// #define INVERT_STEP_PIN true
#define INVERT_DIRECTION_PIN true
#define INVERT_ENABLE_PIN true
#define INVERT_ALARM_PIN true

// Enable servo alarm feedback
#define USE_ALARM_PIN




//================================================================================
//                                 ENCODER
//
// Define the type of encoder you are using on the spindle.  The firmware assumes
// the encoder is turning at a 1:1 ratio with the spindle.
//
// NOTE: the firmware is concerned with the quadrature edge count, which is
// four times the number of pulses.  For example, if you have a 1024 P/R
// encoder, you need to enter 4096 here.
//================================================================================

// Encoder resolution (counts per revolution)
#define ENCODER_RESOLUTION 4096

// Which encoder input to use
#define ENCODER_USE_EQEP1
//#define ENCODER_USE_EQEP2




//================================================================================
//                               CALCULATIONS
//
// Define how calculations should be performed.  Most users will not need to
// touch these settings.
//================================================================================

// Use floating-point math for gear ratios
#define USE_FLOATING_POINT




//================================================================================
//                                HARDWARE
//
// Define which hardware you're using:
//
//  1 - LaunchXL F280049C with ELS BoostXL v1
//  2 - LaunchXL F280049C with ELS BoostXL v2
//================================================================================

// See hardware version table above
#define HARDWARE_VERSION 2


//================================================================================
//                               CPU / TIMING
//
// Define the CPU clock, interrupt, and refresh timing.  Most users will not need
// to touch these settings.
//================================================================================

// Stepper state machine cycle time, in microseconds
// Two cycles are required per step
#define STEPPER_CYCLE_US 5

// User interface refresh rate, in Hertz
#define UI_REFRESH_RATE_HZ 100

// RPM recalculation rate, in Hz
#define RPM_CALC_RATE_HZ 10

// Microprocessor system clock
#define CPU_CLOCK_MHZ 100
#define CPU_CLOCK_HZ (CPU_CLOCK_MHZ * 1000000)


#endif // __CONFIGURATION_H


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## ttabbal (Oct 13, 2020)

What's your pulley ratio? You might need to set STEPPER_MICROSTEPS 3 or similar.


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## GunsOfNavarone (Oct 13, 2020)

Yeah, it's 24/72. I assumed when clough was setting his up (video 10) he went though this big explanation that he's not using a stepper, so he's setting his to 1 and 1000. That must have been the test phase...not the final. I'll try that tomorrow. 10 minutes here, ten minutes there to work on this project. I will say it is SO much quiter with out all those metal gears on gears now, but I'm ready to cut some damn threads!
Thanks @ttabbal


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## devils4ever (Oct 14, 2020)

Yes, you need to account for the pulley ratios in the file. I had to set STEPPER_MICROSTEPS to 3 since I was using a pulley reduction of 1:3 on the stepper drive to the leadscrew.

Also, Cough mentions changes the drive settings to 1000 pulses/rev instead of 4000. From my previous post:
*So, I use the calibration cable from Automation Technologies along with their ESDSeries software and see that the motor is set to 4000 pulses/rev. I set it to 1000...*


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## GunsOfNavarone (Oct 14, 2020)

I looked for your previous post, maybe on a different thread, I didn’t see it here. I’ll have to go back and watch his videos, it’s been a while since I started this project. I do remember him changes steps from 1000 to 4096, your saying you run yours at 1000 micro steps now? Maybe that 4096 was for a stepper nor a servo?


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## devils4ever (Oct 14, 2020)

It took me a bit to find it, but Clough talks about programming the hybrid servo drive in Part 4 of his ELS series around time: 16:00.

Of course, you could leave that and change the Configuration.h file instead. Change the STEPPER_RESOLUTION line to 4000. I think this may cause issues since the servo drive is getting 4X as many pulses and may exceed the maximum frequency.


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## GunsOfNavarone (Oct 14, 2020)

Woah! Wait a second...you say you adjusted the stepper to 1000 not the config.H file?! How the h3ll do you do that? I agree, I think you would exceed its capabilities (maybe not for threading, but for feeding you could) how do I change servo settings?


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## devils4ever (Oct 14, 2020)

Yes, you can program the servo drive via their cable and serial port on your PC. They call it a calibration cable.

Then, you need to download from Automation Technologies the software called Protune. Here's their video.


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## GunsOfNavarone (Oct 14, 2020)

So THIS is what that damn cable the caused me headaches is for...glad I didn’t cut it up to make it work. I remember having a convo here about it when I figured out it was the problem I was having...must be a different thread though. Alright, guess I get to screw around with a bunch of software tomorrow....my FAV!
Thanks Devil!
*edit...no, that’s not the cable I have. Super, got to order that and string this thing out further. Bummer.


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## devils4ever (Oct 14, 2020)

It's pretty easy. The hard part is finding a serial port on your PC! I had to buy a USB-serial cable since most new PCs don't have a COM1 port any more.


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## GunsOfNavarone (Oct 14, 2020)

Yeah, but A.T. Website (link you sent) looks like a serial rs232 to a RJ45 Ethernet? If your saying a USB to serial works...I have that from my old UTEC tuning days...that’s at least a good thing!


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## devils4ever (Oct 14, 2020)

The Automation Tech cable is just a RS232 to RJ45 conversion cable. You need to connect the RS232 side to a serial port on your PC.


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## GunsOfNavarone (Oct 14, 2020)

An RJ45 connects to the servo somehow?? 
seems like USB to serial would be easier...but not if an RJ45 connects to servo. I only use a laptop so it will have to be a USB. Serial just seems so antiquated...


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## ttabbal (Oct 14, 2020)

It's likely the same pinout as the networking guys use for Cisco and others. I have one, but didn't need to use it.


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## GunsOfNavarone (Oct 14, 2020)

OK, watched the video about programming drive...I see where the RJ45 comes into play now. Anyone know the difference between" resolution" and "pulses per circle"? That seems to be the options in Protune and 4000 seems to be factory setting for both.. I might just go ahead and try to make an adapter rather than wait to order one. Being there are pinouts available and I believe it only uses 6 of the 25, shouldn't be too complex.


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## devils4ever (Oct 14, 2020)

I wouldn't change too much unless you know the outcome. I only changed the one parameter.


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## GunsOfNavarone (Oct 14, 2020)

And that one parameter was...resolution?


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## devils4ever (Oct 14, 2020)

Pulses/rev = 1000


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## GunsOfNavarone (Oct 14, 2020)

A mixed blessing here since I need to reflash the launch board. I checked Clough's Github, there is a new version and you can now POWER OFF THE UNIT WITH THE POWER BUTTON!!! Nice...


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## devils4ever (Oct 15, 2020)

Nice. I see he changed the tach display to reduce jitter also. That will be nice since the tach jumps around a lot.


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## devils4ever (Oct 15, 2020)

I just updated and I like that the tach doesn't jump around as much. The power switch change is okay, but I need to power off my power supply to the motor drive anyways.


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## GunsOfNavarone (Oct 15, 2020)

Yeah, It sort of put control panel in a lesser power setting for me. RPM gauge seems to still be on though the panel is "off". On a related note, during that flashing and changing my gearing steps to 3:1, I did a scratch pass at 8 tpi, came out at 32 tpi. This is better, but the pulse per rev does seem to be 4x  (4000 not 1000) Trying to get a cable to change this setting...


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## kb58 (Oct 17, 2020)

Short story: Do not load "testfixture-f280049c" into the eval board.

Long story: The previous version of ELS was running fine. Downloaded the new one, compiled it without error, downloaded it to the eval board, and... it's dead. The display shows RPM as "7_" and FEED is "88888", plus all the LEDs on the top row are lit. The only activity on the eval board is LED5, which is flashing fast. Downloaded the old version of ELS again and that works fine. 

Thought maybe I need to update Code Composer, (I'm running 9.2.0.00013). The update failed part way through... sigh. Reverted back to the version above.

Confirmed that the earlier version of the ELS always works and the new version always fails, meaning it's software. The odd thing was that when the v1.3.01 project was loaded, three files appear:
electronic-leadscrew1.3.01
els-f280049c
testfixture-f280049c

Only that last one could be changed to "[Active - Debug]" by clicking on it, none of the others did. That seemed suspicious and I wondered if I'd somehow downloaded an interim test version off GitHub. Sure enough, that was it, but I can't tell you the rev since it crashed the eval board. So, don't click on testfixture-f280049c; it's els-f280049c that has to be loaded into the board.  Just posting this in case any of you fellow travelers run into the same thing! Maybe James came move testfixture-f280049c to somewhere less accessible on GitHub.


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## kb58 (Oct 17, 2020)

GunsOfNavarone said:


> Yeah, It sort of put control panel in a lesser power setting for me. RPM gauge seems to still be on though the panel is "off". On a related note, during that flashing and changing my gearing steps to 3:1, I did a scratch pass at 8 tpi, came out at 32 tpi. This is better, but the pulse per rev does seem to be 4x  (4000 not 1000) Trying to get a cable to change this setting...


It's supposed to do that. Watch his latest youtube video, where he explains what's going on (though your tpi issue is something different)


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## kb58 (Oct 17, 2020)

GunsOfNavarone said:


> There were duplicate files so bring in new ones that had same name...issues. Fixed that, but now when it gets to "ice pick" running, I immediately get this message.
> View attachment 339596


It's telling you that the USB interface chip on the eval board needs updating. I let it do its thing and the warning went away.


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## GunsOfNavarone (Oct 17, 2020)

@kb58 I'm confused if you're having issues, but I will say that I couldn't open files either, it said something to the effect that those files were already opened.  The code composer holds files until you actually remove them from Code Composer. Its actually a delete that gets them out (but not off your computer. I didn't have issues with the latest upload, sounds like devil here didn't either. Must be a setup difference.
My only issue now is needing that driver programming cable that's on its way. Soon...soon I will finally be done with this project. I learned more than I wanted to about software that runs this stuff behind the scenes and how these things work a bit better. I really wished I had picked up on the changes I needed to do to match what Clough ended up with. Live/learn!


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## devils4ever (Oct 18, 2020)

I created a new workspace called *workspace_v9_2* and downloaded the new code there. I had no issues compiling and downloading the debug and release versions to the PCB. This way I can go back to the old version without issue since that workspace *workspace_v9 *is untouched. Try that.

After using the new version a little making a metric thread, I like it. I like that when you use the power switch, it shuts down the motor drive, but keeps the RPM display. This is useful for keeping the leadscrew idle when facing a part, but still get tach info. Less jitter on the tach display is great. I don't have a carriage lock on my mini-lathe, so I use the idle leadscrew and clamp the half nut to it to keep the carriage stable while facing.

He goes over all the updates in Part 20 of his YouTube ELS series.


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## devils4ever (Oct 19, 2020)

Here's some test threads done in 6061. They are M20 X 2.5 threads in both a bolt form and nut form. Everything seems good with the new software.--version 1.3.01.


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## GunsOfNavarone (Oct 19, 2020)

Looks awesome! I am excited to not take 10 minutes to setup lathe to cut different threads more than anything else.
Since you cut metric, what was your technique with the new system? I assume you got to gutter, stopped, backed compound out, reversed and repeat? I mean, I know some people will still disengage half but at gutter, hit reverser and lock the half but at the same thread dual setting as what they went in with.
I’m interested to see which I prefer going forward...it’s always been the 1st version, but now I’m threading at 60 rpm vs 150 previously.


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## kb58 (Oct 19, 2020)

devils4ever said:


> Here's some test threads done in 6061. They are M20 X 2.5 threads in both a bolt form and nut form. Everything seems good with the new software.--version 1.3.01.


Though it's probably fine, try screwing one of your fabricated parts into a commercial part. Reason being, if there's a scaling problem in the software, it won't appear because a wrongly-threaded nut will always fit a matching wrongly-threaded screw.


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## devils4ever (Oct 19, 2020)

I cut mostly Imperial threads. This is probably the 5th or 6th metric thread I've cut! I wanted to see how it works with an Imperial leadscrew. My lathe has a 16 TPI for the leadscrew.

So, here's my technique for external threads are:

Cut small gutter by end of cut.
Cut small bevel at start of cut.
Set compound to 29-1/2 degrees.
Square cutter.
Turn on lathe and advance cutter until it just starts to cut.
Turn off lathe.
Zero cross slide and zero compound.
Position cutter for start of cut.
Engage half-nut and leave it engaged for entire process!
Turn on lathe to low speed (100-200 RPMs) and stop at end of cut--this is easy with the variable speed motor. Can also be advanced by hand if a little short.
Back off cutter with cross slide to clear part.
Reverse motor (spindle direction) and bring back to start.
Turn in cross slide and bring to zero.
Use compound to advance cutter to cut thread. I use about 3-5 thou DOC at start and finish with 1-2 thou along with some spring passes.
Repeat as needed.
I usually start checking the thread with a thread mic when I'm in about 80% in based on the formula 0.75/TPI. So, for this thread, I converted 2.5 mm pitch to 25.4/2.5 = 10.16 TPI. Compound feed = 0.75/10.16 = 0.0738".


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## devils4ever (Oct 19, 2020)

kb58 said:


> Though it's probably fine, try screwing one of your fabricated parts into a commercial part. Reason being, if there's a scaling problem in the software, it won't appear because a wrongly-threaded nut will always fit a matching wrongly-threaded screw.



You are correct. I did cut a M8 with the old software and tried it on a commercial nut with success. I didn't have a M20 bolt or nut, so I made both, but they could be off. I did check with a metric thread gage though.


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## ttabbal (Oct 19, 2020)

Good looking parts! I usually thread away from the chuck, so I just let it overshoot, back the tool out, and reverse to the start. With metric, I leave the half nuts engaged as I have an imperial leadscrew. 

If you need or want interoperability, measure the outside thread with a thread mic or wires. Then use it as a gauge for the internal thread.


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## devils4ever (Oct 19, 2020)

ttabbal said:


> Good looking parts! I usually thread away from the chuck, so I just let it overshoot, back the tool out, and reverse to the start. With metric, I leave the half nuts engaged as I have an imperial leadscrew.
> 
> If you need or want interoperability, measure the outside thread with a thread mic or wires. Then use it as a gauge for the internal thread.



That's exactly what I did. 

When I was first learning how to cut threads (not long ago), I cut away from the chuck figuring it was safer. I couldn't figure out why the thread I cut wouldn't engage the nut. Finally it dawned on me that I cut a left hand thread! I've seen Joe Pi's method of cutting threads on the lathe by cutting away from the chuck, but that method puts upwards pressure on the tool and tool holder and I'm not sure my little lathe would like it that much.


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## GunsOfNavarone (Oct 19, 2020)

ttabbal said:


> Good looking parts! I usually thread away from the chuck, so I just let it overshoot, back the tool out, and reverse to the start. With metric, I leave the half nuts engaged as I have an imperial leadscrew.
> 
> If you need or want interoperability, measure the outside thread with a thread mic or wires. Then use it as a gauge for the internal thread.


And now with the ability to have the lead screw move in the opposite direction as chuck, this is now something I can do now. Can run at a higher rpm with no stress of stopping in time!


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## GunsOfNavarone (Oct 19, 2020)

devils4ever said:


> That's exactly what I did.
> 
> When I was first learning how to cut threads (not long ago), I cut away from the chuck figuring it was safer. I couldn't figure out why the thread I cut wouldn't engage the nut. Finally it dawned on me that I cut a left hand thread! I've seen Joe Pi's method of cutting threads on the lathe by cutting away from the chuck, but that method puts upwards pressure on the tool and tool holder and I'm not sure my little lathe would like it that much.


I think it was Joe Pi that has a video where he is cutting threads (metric on an imperial L.S.) and he does disengage. However, when he reverses direction, he engages half but at the same point he started. Works well and it’s nice to be able to disengage before getting in too far. VFD has helped a bit with slowing quicker, but my resistor doesn’t allow for solid breaking like some do (Teco L510)


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## devils4ever (Oct 22, 2020)

Here's a M20 X 2.5 thread cut in 1144 steel. I wanted to try this in harder material plus I needed this cut for another project.

The 2.5 mm pitch is equivalent to about 10 TPI which is pretty coarse and pushes the stepper motor to higher speeds. I really wanted to see if the ELS system could cut this coarse a thread in steel (harder) stock without missing a step. It worked great. Of course, I was only running the main spindle between 100 and 250 RPMs, but the leadscrew is turning faster than the main spindle since my leadscrew is 16 TPI.

I'm very happy with the finish. Near the end of the cut, I can only take 1-2 thou per pass. That's a limitation of the mini-lathe, not the ELS.


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## GunsOfNavarone (Oct 23, 2020)

So....FINALLY got the last piece of the puzzle buttoned up. Changed the stepper to 1000 step/rev. Ran a couple thread tests, look great. I did turn the RPMS way up (1800) and I was able to error the stepper out, but that was at 8tpi. It was trying to move stepper faster than it's ability. I don't think I'll ever want/need to do ANY threading at 1800 rpm. I do want to play more with any limitations, but just glad all the little details are done. Nice smooth finish when power feeding. I feel like my power supply for steeper should be grounded. I mean the plug has a ground, but it attached to the bottom side of a butcher bock work table, but the CASE isn't ground that way. Not sure if that's a problem TBH.


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