# 13 tpi



## Aukai (Apr 10, 2020)

Messing around playing with the threading going through different sizes I was looking at the 1/2" 13 tpi. My 1228 has 11, 12, 14, so what is the work around? I guess I do not have the right search words...


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## mikey (Apr 10, 2020)

Do you have a change gear set for your lathe? The manual should show you the necessary combination of gears to get 13 tpi.


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## Aukai (Apr 10, 2020)

Never mind, it was all by it's self on a single line past the normal tpi's, and the metrics, in between the inch per rev for facing, turning charts. Good Lord you have to change gears for this one thread...


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## mikey (Apr 10, 2020)

I do. 

My Emco lathe can cut a huge number of threads, including Diametral and Modular pitches so I don't look at it as a hassle; it is an impressive capability in my point of view.


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## Aukai (Apr 10, 2020)

I still have to figure out the schematics of what gear to change.... 

 Dave


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## devils4ever (Apr 10, 2020)

I'm thinking of converting my Mini-Lathe into one with an Electronic Lead Screw to avoid the gear changing hassles. I'm wanted to convert my mill to CNC first to help make the parts and now I'm done with that.


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## Aukai (Apr 10, 2020)

Is there one that does not have to use a VFD?


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## devils4ever (Apr 10, 2020)

The ELS replaces the gear train with a shaft encoder to detect the position of the main spindle and a stepper motor to drive the lead screw. The lathe is still powered as it was before conversion.

To get a feel for this, check out this series on YouTube by Clough42. This is path I'm thinking of taking.


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## RJSakowski (Apr 10, 2020)

Aukai said:


> Is there one that does not have to use a VFD?


My G0602 doesn't have a VFD and I installed a ELS based on Clough42's design.  No more gears and inch and metric threads, left and right hand threads, and feeds left and right drom .001"/rev. to .040" all at the push of a few buttons.


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## macardoso (Apr 10, 2020)

mikey said:


> My Emco lathe can cut a huge number of threads, including Diametral and Modular pitches so I don't look at it as a hassle; it is an impressive capability in my point of view.



Mikey, I have always wondered this, what does a machinist use a Diametral or Modular pitch "thread" for? Only thing I came up with was making gear cutting hobs but I don't even know if that is correct.


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## devils4ever (Apr 10, 2020)

RJSakowski said:


> My G0602 doesn't have a VFD and I installed a ELS based on Clough42's design.



Did you use/buy the PCBs and the software from him?


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## RJSakowski (Apr 10, 2020)

devils4ever said:


> Did you use/buy the PCBs and the software from him?


Clough has a list of all the components in one of the later video.   He also has a project on GitHub.

Basically, it required a stepper or servo motor and driver, a rotary encoder, a display pcb, and a micro controller, power supply, and some mechanicals; all off the shelf.  There was one pcb that I bought from him for a round $20 shipped.  My total cost was something like $230, using all new components except for the power supply for the motor/driver.  Adding the power supply would have increased the cost to $270.

If you search on this forum for Clough42 and electronic lead screw, there are a couple of very long threads on the subject.


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## Aukai (Apr 10, 2020)

Some assembly required


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## 7milesup (Apr 10, 2020)

RJSakowski said:


> Clough has a list of all the components in one of the later video.   He also has a project on GitHub.
> 
> Basically, it required a stepper or servo motor and driver, a rotary encoder, a display pcb, and a micro controller, power supply, and some mechanicals; all off the shelf.  There was one pcb that I bought from him for a round $20 shipped.  My total cost was something like $230, using all new components except for the power supply for the motor/driver.  Adding the power supply would have increased the cost to $270.
> 
> If you search on this forum for Clough42 and electronic lead screw, there are a couple of very long threads on the subject.



That is really cool RJ.  THank you for sharing that.  Ugghhhh though, now another project on my list.


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## RJSakowski (Apr 10, 2020)

7milesup said:


> That is really cool RJ.  THank you for sharing that.  Ugghhhh though, now another project on my list.


It has been a few months since I last checked on the ongoing project.  ne improvement that I would like to see in the Clough42 project  is the ability to enter any desired thread pitch rather than selecting one from the list.  Fortunately, the design is such that software updates can easily be loaded into the microprossesor if/when this should happen.  Another option would be if I bucklesd down and rewrote the source code myself.  Not an insignificant task for me.


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## mksj (Apr 10, 2020)

These ELS are also worth looking into, in particular if you want an integrated DRO with your ELS. Also can adjust speed if you are using a VFD.








						The electronic leadscrew - ELS 4 - Rocketronics English
					






					www.rocketronics.de


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## RJSakowski (Apr 10, 2020)

The Rocketronics ELS is definitely more versatile, providing both x and z synchronized movement.  It is also considerably more expensive at $300-$600 more than a Clough42 system.  However, the integral DRO is a nice feature which will offset the additional cost by $200 - $400 and there is merit in having a pre-assembled control.

You are starting to get up to the cost a full CNC system though and being able to write custom machining programs would be an added feature.


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## ttabbal (Apr 10, 2020)

I'm using the clough42 ELS. It's been a very worthwhile upgrade. I did buy his PCB. But I could have easily made my own board. You do have to make mounts and such to fit your lathe though. 

It could be expanded to CNC, but I don't want to go there right now, maybe ever. 

I've always thought that 13TPI was a bit odd. I don't really understand why there are so many thread pitches.


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## pstemari (Apr 12, 2020)

macardoso said:


> Mikey, I have always wondered this, what does a machinist use a Diametral or Modular pitch "thread" for? Only thing I came up with was making gear cutting hobs but I don't even know if that is correct.


Cutting worm gears, either in inch or metric sizes.

Sent from my Pixel XL using Tapatalk


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## Bamban (Apr 12, 2020)

mksj said:


> These ELS are also worth looking into, in particular if you want an integrated DRO with your ELS. Also can adjust speed if you are using a VFD.
> 
> 
> 
> ...



Would any of their complete kits be stout enough to drive a 1236 lathe?


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## mksj (Apr 12, 2020)

The ELS4 is just the controller, so you can put whatever driver/drive you choose (DC stepper, DC servo or AC servo). A Nema 24 motor with 2.2 Nm torque on a 4 mm spindle generates a thrust of about 1400N, which corresponds to a weight of 140 kg pulling on the bed slide. The ELS4 is more of a full featured ELS in that it drives both the X and Z axis, and has a higher level of automated control, so like with threading it can do a number of different cutting profiles such as radial, flank infeed, modified flank infeed, and alternate flank infeed. So semi-CNC functions.


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## Winegrower (Apr 12, 2020)

For some reason, my lathe also does not handle 13 TPI without a gear change.   I wouldn't care, except that the hold down rods and nuts for the Bridgeport are all 1/2-13 threads.   Occasionally I wish I had a particular length rod, but it's not worth changing gears, so far.


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## mikey (Apr 12, 2020)

pstemari said:


> Cutting worm gears, either in inch or metric sizes.
> 
> Sent from my Pixel XL using Tapatalk



This. Diametral for Inch and Modular for Metric worm gears.


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## RJSakowski (Apr 12, 2020)

Bamban said:


> Would any of their complete kits be stout enough to drive a 1236 lathe?


As far as I know, they don't include the stepper/servo motors and drivers nor the encoder.  This from their ELS4 user manual.

You would have to pick those items to meet your requirements.


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## macardoso (Apr 12, 2020)

I rarely walk up to my lathe and just quickly pop something out. Lately I'm often doing complicated setups with indicators that might take an hour or two to get going. In this context, changing gears to cut a particular thread isn't a big deal to me and just seems like part of the normal process for setting up a part. 

If you need quick and convenient, an ELS seems reasonable but you can also look for a geometric die head which would make short work on repeated threads.


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