Are The Moon's TSM Integrated Step-Servo Motor Compatible With Acorn?

[ChrisMe]

I'm looking at using the Moon's Integrated Step-Servo motor TSM23P for my first CNC lathe build. They work in pulse mode so as far as I can tell should work with Acorn and because they are integrated that should simplify things a bit for me as I don't need to worry about drivers. Is anyone able to offer a review on these? The encoder is 20,000 line so they should be incredibly accurate.

Website-
https://www.moonsindustries.com/p/nema- ... 6351000906

TSM23P Integrated Step-Servo Instructions-
https://www.moonsindustries.com/medias/ ... hment=true

TSM Integrated Step-Servo Brochure-
https://www.moonsindustries.com/medias/ ... hment=true

[jpmsteadi]

Based on reading the manual briefly I think they should be compatible. If you were going to go with the integrated step and dir servos I would suggest going for the clearpath SDSK ones from Teknic. There is way more information about them on the forum and online and many folks with successful build, myself included.

Here is a link to a similar torque specced one as the one you listed (about 1.5 Nm of cont torque: https://www.teknic.com/model-info/CPM-S ... voltage=75

It also seems to be cheaper than the one you suggested?

Also keep in mind as for the resolution of the motor: using a standard 5mm pitch ball screw means you will go 5mm with one rotation. So even the lower resolution motors from Clearpath (they offer 1/800th of a rotation and 1/6400 of a rotation encoders) will still give you an effect resolution at the ballnut of around 2 tenthousanths of an inch (about .006mm). I doubt any conversion machine is going to be able to do anywhere near that in effective accuracy. With the slightly more expensive enhanced 1/6400 rotation encoder you are looking at .0008 mm of resolution, less than a micron. 20,000 counts per rev is overkill.

[ChrisMe]

Based on reading the manual briefly I think they should be compatible. If you were going to go with the integrated step and dir servos I would suggest going for the clearpath SDSK ones from Teknic. There is way more information about them on the forum and online and many folks with successful build, myself included.

Here is a link to a similar torque specced one as the one you listed (about 1.5 Nm of cont torque: https://www.teknic.com/model-info/CPM-S ... voltage=75

It also seems to be cheaper than the one you suggested?

I think that is a good call. The only downside is I was going to run this on a Sherline Chucker lathe and was having issues with shaft size as they only seem to make 1/4inch (6.35mm) shaft for that lathe. I spoke to them and they said they would make me an 8mm coupling however they may very well make me a 3/8 inch so I can use that motor. Do you know how many lines or PPR they are?

[jpmsteadi]

They come in two "flavors" - Regular and Enhanced. The regular is 1/800th of a turn resolution and the enhanced is 1/6400 of a turn. Unless you are really really strapped for cash or can get a screaming deal on the regular the enhanced is only about $45 USD more and I think worth it.

You can find basically ever adaptor size for shaft couplers on mcmastercarr: https://www.mcmaster.com/couplings/flex ... plings-11/

or if you are cheaper search around on ebay or amazon.

On the sherline chucker lathe you should be able to get away with pretty small motors. I would see what the torque spec for the steppers you can buy through them are and size the servos similarly.

[ChrisMe]

On the sherline chucker lathe you should be able to get away with pretty small motors. I would see what the torque spec for the steppers you can buy through them are and size the servos similarly.

The high torque option is 1.5Nm so I was going to stick with that. I looked at McMasters however the Sherline Coupling is needlessly complex. It is part number 59105 that I have drawn a red box around. I might buy their 1/4 coupling and boar it out myself.

[jpmsteadi]

oh weird. That is strange. I guess they are using the coupler as a way to put contact bearings in it too for support. As opposed to having those separate.

I imagine as long as its bored out perfectly concentric (or as close as possible) there wouldn't be any issues. I don't like that it uses a setscrew instead of a clamp...

I would say that a peak torque figure of 1.5 is probably good for that lathe. The motor I linked to is a continuous torque of 1.5nm. That is most likely overkill.

[ChrisMe]

I don't really like the coupling system either but there mini lathes are good and as I'll be making small parts (under 4mm) there is not a lot on the market. I did consider for a future project making the coupler into a shaft then adding a standard flexi coupler between it and the motor but that is some way away

[jpmsteadi]

makes perfect sense. That was my approach too. Get it running first, then figure out what improvements to make.

Best of luck on the project!

[ChrisMe]

makes perfect sense. That was my approach too. Get it running first, then figure out what improvements to make.

Best of luck on the project!

Thank you for your input by the way. It has been a big help.

[jpmsteadi]

makes perfect sense. That was my approach too. Get it running first, then figure out what improvements to make.

Best of luck on the project!

Thank you for your input by the way. It has been a big help.

of course! more than happy to help!