View Full Version : advice on shafts & pulleys

Lee Alkureishi
04-30-2012, 5:20 PM
hi all, I am hoping someone here can give me some advice regarding my project upgrading my lathes motor.

I'm replacing the existing motor with one pulled from a treadmill. The easiest way id to create an intermediate 5/8"shaft with 2 pulleys - one connects to the headstock spindle, and one connects to the new motor.

I looked on Mcmaster-carr.com, but there's a huge variety of pulleys to choose from, and I didn't find any reasonably priced ones that match the belt type from the treadmill motor. It's a 1/2" wide flat belt with 5 grooves.

Hoping someone can advise on what to look for - having fun with this project, but if I have to spend $100 on pulleys, then it doesn't make much sense to continue with it!

Thanks in advance,


curtis rosche
04-30-2012, 5:37 PM
replace the pulley on the motor. much easier

Lee Alkureishi
04-30-2012, 6:56 PM
Hi Curtis,

Thanks for the reply. I looked again at the motor, but I'm not sure how to get the existing pulley off. It doesn't look like there's a set screw or any other accessible mounting mechanism. I've attached a picture for illustration.

I'm wondering how much of the existing setup I could make use of, though. As it stands, the motor drives a large nylon grooved pulley, which turns a ~42mm steel shaft. This would originally have turned the tread for the treadmill. Would it be feasible to turn a maple pulley and attach it to this existing shaft? Then I could run a v-belt from the wooden pulley to the headstock...

Are there problems associated with using hardwood pulleys (apart from not lasting as long...)? It looks like people with homemade lathes use them all the time..

Thanks again for any advice,


David G Baker
04-30-2012, 7:37 PM
The highest priority is can you control the motor? I thought about doing something similar but my controls were not working so I gave up. I never got as far as changing pulleys or shafts.

Jerry Bruette
04-30-2012, 11:49 PM
That's a micro groove pulley and belt. Not sure how you'd convert it to a regular V belt. Maybe you could find a pulley on ebay.


curtis rosche
05-01-2012, 12:09 AM
i have the exact same motor, i havent seen it in awhile but if i remember, if you hold the little bit of shaft that comes out the other side, you can unscrew the pulley, its threaded on. it might have some thread lock on it.

or, you could just use a vbelt pulley for a B-sized belt. it should work, but it might wear the flat belt a little bit quicker, but it should work.

turning your own pulley shouldnt be too terribly hard. go look at the owwm forum, plenty of flat wooden pulleys over there

curtis rosche
05-01-2012, 12:11 AM
i couldnt figure out how to hook up the control board on mine, so i picked up a UNIdrive for $20, now i have 9 speeds with gears

Lee Alkureishi
05-01-2012, 12:20 AM

I was planning to use the existing controls from the treadmill. It was a fully working treadmill I got for $30 on craigslist, so I pulled it apart, removed the frame and now have the motor unit (pictured) with a control box attached by a network cable. It'll look a bit funny on the front of my lathe, but it all seems to work the way I'd want it to. I haven't heard of anyone else using the existing controls (most websites suggest using control boxes from ebay) - is there a reason not to?

Curtis: thanks for the advice - I'll take another look at it tomorrow. Good to know I have multiple options! What kind of lathe did you attach the motor to?


curtis rosche
05-01-2012, 12:24 AM
i wanted to attach it to a 9 inch craftsman lathe from the 1920s, but didnt cause i coulnt get the controls to work and had trouble making my own power supply to make my own controls.

i couldve tried again on my semi custom lathe, but i found a 2hp hi torque motor for $5 so i used that with the gear box

Lee Alkureishi
05-01-2012, 8:55 AM
i found a 2hp hi torque motor for $5

Can I have one please?


curtis rosche
05-01-2012, 10:30 AM
if i could find them every week i would be selling them for profit ;)

the good deals are during mudsale season. thats where i got the motor. or if you go to a salvage yard. one near me has a pile about 20ft high of motors. most dont work, but if you can find one that does, they sell it by weight of copper/steel.

Mike Cruz
05-01-2012, 10:46 PM
Yeah, those flat belt pulleys will break the bank. Just replace the pulley...