New VFD plus 1 HP Motor for Mini Lathe or any lathe

[PJs]

Hi JR
Great work on your new drive arrangement, you mention using V belts, have you considered Poly v belts. I have used one on my countershaft drive for some years now and they run really smoothly and the pulleys are easy to machine, never had a problem with slip either.

I was thinking the same thing last night Olderdan or even a toothed belt. SDP/SI has a full line of toothed, grooved, O'ring, flats and V belts and pulleys for fractional hp use and are even better for torque. Although making the pulleys for a Groove belt would be easier and a fun challenge.

[jjr2001]

Hello Dan and PJ, The belts are very interesting with so many types out there.
I did use a Poly segmented v-belt on my CNC spindle and no problems at all.
Nice small profile. Seems they use these on vacuum cleaners and sewing machines.

I wanted to try a 3L section Kevlar belt for the lathe and see how that works out.
The belts are available for a good price and they look tough.
Both the lathe to jack shaft set and the motor to jack shaft set will be replaced.
I planning to have them on hand should all the teeth on my timing belts disappear! LOL


Thanks for all the suggestions and comments

Cheers, JR

[rossbotics]

Nice work Jr
I have a smaller lathe similar to yours that I would love to do something like that to as well, I'm sure you'll enjoy the fine RPM adjustments, my 6913 Clausing Lathe has a variable speed drive, hydraulic adjustable sheaves, it's really nice to fine tune the RPM's for your work.

Again Great Job
Doug

[jjr2001]

Thanks Doug, If you noticed the 2.5" diameter stock in the lathe in two of the pictures you will see some
of the stock I was turning when the original motor gave it up. It cut like butter after I put the new motor/vfd
on the lathe. Very happy with the huge increase in torque.

That 2.5" diameter chunk in the lathe is in the process of being turned into your Universal Grinding Fixture.

Cheers, JR

[threesixesinarow]

What kind of belt do the one speed brushless mini lathes use? I switched to XL first on my old 7x10 - 3/8” wide ones fit under the belt cover, but they’re only a little stronger than the similarly old fashioned original metric timing belts. They’re easy to find, though, and are easier to replace than headstock gears.

I think more modern timing belts have bigger capacity.

[jjr2001]

What kind of belt do the one speed brushless mini lathes use? I switched to XL first on my old 7x10 - 3/8” wide ones fit under the belt cover, but they’re only a little stronger than the similarly old fashioned original metric timing belts. They’re easy to find, though, and are easier to replace than headstock gears.

I think more modern timing belts have bigger capacity.

Hi Threesixesinarow, Not sure what the older single speed lathe uses but I have had the little timing belt rip out on my lathe several times. It is a 3mm pitch and I think like you mentioned if they would have used a 5mm pitch it would have been a lot stronger.

I am thinking that I would rather have the drive belt slip than rip out the teeth! We will see down the road which approach is the best for me.

Thanks for the comment,

Cheers, JR

[threesixesinarow]

My 7x10 has a poly-vee belt drive now, with a 6-rib J-section belt to the headstock countershaft running on a pair of 1-1/4” pulleys. It hasn’t slipped but my collets only take up to 9/16”, so it’s hard to compare.

My mill has 3-rib J belts on slightly bigger pulleys and in low gear they can slip, even with just a 350W motor.

[jjr2001]

My 7x10 has a poly-vee belt drive now, with a 6-rib J-section belt to the headstock countershaft running on a pair of 1-1/4” pulleys. It hasn’t slipped but my collets only take up to 9/16”, so it’s hard to compare.

My mill has 3-rib J belts on slightly bigger pulleys and in low gear they can slip, even with just a 350W motor.

Interesting. My mini mill (500 watt) has never slipped. It uses a timing belt also but it is much wider than the lathe belt and I think it is a 5mm pitch.
Cheers, JR