Vee belts for lathe

All discussion about lathes including but not limited to: South Bend, Hardinge, Logan, Monarch, Clausing and other HSM lathes, including imports

Moderators: GlennW, Harold_V

Post Reply
Mr Ron
Posts: 2126
Joined: Tue Dec 22, 2009 12:36 pm
Location: Vancleave, Mississippi

Vee belts for lathe

Post by Mr Ron »

I think the twin vee belts on my Sheldon lathe are stretched beyond their limit. After all, they are probably about 65 years old (original). Not wanting to disassemble the arbor and pulleys from the under drive, I want to use link belts. The link belts have an arrow to indicate direction of rotation. Since the lathe has reverse, would it then matter which way the arrows point? I would normally set the vee belts for forward drive.
Mr.Ron from South Mississippi
Russ Hanscom
Posts: 1955
Joined: Wed Mar 15, 2006 11:10 pm
Location: Farmington, NM

Re: Vee belts for lathe

Post by Russ Hanscom »

Where is the fun in that? I changed the belts on my Sheldon a number of years ago, did not even think of link belts. About a day to remove the spindle and replace, if I remember correctly. I also replaced a few of the lower end bearings which needed it.

Your direction proposal makes sense.
SteveM
Posts: 7763
Joined: Mon Jun 27, 2005 6:18 pm
Location: Wisconsin

Re: Vee belts for lathe

Post by SteveM »

The link belts do have a direction, and they don't give a "this is what will happen if you run it in reverse" comment, so I don't know what the effect would be.

I have run my atlas in reverse with a link belt, but since I have a threaded chuck, it was only very slow to remove a tap or die from a part, not anything with a cutting tool actively cutting.

The other thing I would worry about is matching. You can get a matching set of V belts for where there is a double pulley system. Not sure if the tolerances on link belts are good enough to get a close enough match.

Steve
John Hasler
Posts: 1852
Joined: Tue Dec 06, 2016 4:05 pm
Location: Elmwood, Wisconsin

Re: Vee belts for lathe

Post by John Hasler »

SteveM wrote: Tue Nov 26, 2019 3:53 pm The link belts do have a direction, and they don't give a "this is what will happen if you run it in reverse" comment, so I don't know what the effect would be.

I have run my atlas in reverse with a link belt, but since I have a threaded chuck, it was only very slow to remove a tap or die from a part, not anything with a cutting tool actively cutting.

The other thing I would worry about is matching. You can get a matching set of V belts for where there is a double pulley system. Not sure if the tolerances on link belts are good enough to get a close enough match.

Steve
My Avey came with triple link belts. They seem to work fine together.
TRX
Posts: 162
Joined: Wed Aug 20, 2008 7:30 pm
Location: Central Arkansas

Re: Vee belts for lathe

Post by TRX »

The link belts won't grip the pulleys as tightly in reverse, and can slip.

The only time I've ever used reverse was when threading away from the headstock. That doesn't take much oomph.

Note if you put new V belts on the Sheldon, it probably uses "industrial" or "compressor" belts, which are shallower than automotive V-belts. Most auto parts can get industrial belts in a day or two if you don't want to order online. And you can order industrial belts in matched pairs or sets.

I learned about this after putting new belts on my drill press; they just squealed and smoked instead of turning the drill. Only the bottom flat area was riding on the pulleys, the sides weren't touching at all! Proper industrial belts fixed that easily enough.
armscor 1
Posts: 311
Joined: Sun Jun 12, 2016 3:12 am
Location: Philippines

Re: Vee belts for lathe

Post by armscor 1 »

My Dean Smith and Grace had 5 "B" section link belts between gearbox and spindle and never had a problem running Fwd or Rev.
The drive pulley had a built in eccentric so you could loosen the belts to remove links to increase tension on the belts.
It gave a smooth transition from gearbox to spindle and protected gearbox from interrupted cuts.
Post Reply