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darryl
02-23-2013, 10:33 PM
Just wondered- since I've never used a leather belt for anything except holding up me trousers, is there a preferred side to use against the pulleys? Offhand I'd think that the inside would have better grip, but my work with leather has been making wallets and purses, etc. Aside from vintage machinery, are leather belts still in use? Where might they actually be an optimum choice?

J Tiers
02-23-2013, 10:57 PM
They work, may not be "optimum", that's probably a 'composition", rubber and fiber type.

The hair side (smooth side) goes against the pulley.

That sounds counter-intuitive, but it isn't. A good belt is not stiff, it "lays" on the pulley, and grips tight, just like a very slightly damp hand on a smooth pipe..... that'll about rip your skin off, and the belt if properly treated, should grip like that.

Don Young
02-23-2013, 11:49 PM
I think most old leather belt drive machines had belts that were well capable of transmitting the required and/or available power. They do need more attention and replacement than more modern drives.

JRouche
02-23-2013, 11:53 PM
Just wondered- since I've never used a leather belt for anything except holding up me trousers, is there a preferred side to use against the pulleys? Offhand I'd think that the inside would have better grip, but my work with leather has been making wallets and purses, etc. Aside from vintage machinery, are leather belts still in use? Where might they actually be an optimum choice?

Yes, they are still used, for old equiptment. I bought a new belt for my old southbend lathe and fixed it up with the alligator clips. But after reading Jerrold's post I may have it on reverse. I have the furry side down on the pulley and the smooth side up. I didnt have any instructions so went with what I thought waqs correct.

One being the leather itself. Ive worked with leather. Making belts, yes pants belts and guitar belts. I always looked at the material with how it came off the cow. The outside always went outside. So I laced the drive belt up the same way.

My thinking for the drive belt wasn't so much how it would grip. I had a feeling it would hold a grip the same inside or out. So then it came to durability for the belt. The outside has ALWAYS been the outside for these hide belts. Think about the structure of the hide. Its fibrous and has long strands and short strands. When it was wrapped around the animal the skin gave and stretched. So it produced "strands" that were aligned for that stretch. Even when dried those "stands" held some memory. My thinking was if I ran the belt around the pulleys inside out it would tend to break the strands VS if the belt was wrapped around the pulleys in the "normal" configuration.

And I have seen belts forced backwards and the inside gets torn and the outside gets compressed. I say run her like the cow did. JR

Duffy
02-24-2013, 10:19 AM
Logan 820 and relatives use leather belts. I think that they changed about 1950 or thereabouts. I bought my replacement from Tandy Leathercraft. I thought about lacing it and then chickened out and used a clip.
As an aside, Upper Canada Village, near Cornwall Ontario, had a 50 HP steam engine using a leather belt drive. I was told that the belt was made in England, and it cost, in 1967, $5000.00 Cdn. It is a series of strips of cowhide spliced together to a length in the order of 100 feet. It is impressive to see it operating, but it is almost certain that it has NEVER transmitted the full power of the engine, since this is a "living history" display driving a series of spinning machines and looms, but producing no product.

gizmo2
02-24-2013, 10:27 AM
There's a fellow out here in cyberspace selling synthetic belts. I put one on my SBL about 6 years ago, power transfer is very good but more importantly stretch is minimal. It was also cheaper at the time. Without hesitation, I would buy another but I doubt this one is going to wear out in my lifetime.

Dr. Rob
02-24-2013, 10:43 AM
There's a fellow out here in cyberspace selling synthetic belts...

Tony Griffiths, the Lathes.Co.UK guy. See the main page of his site; there is a little info page on various types of belts, (including leather) splices, clips, prices and so on.

.

darryl
02-24-2013, 10:04 PM
I had a thought- since I've been in a bit of a belt making mood- what would be wrong with making your flat leather belt, gluing the ends together with just about any flexible glue, turning the grip side inwards, then layering on some tool handle coat or urethane rubber compound along with one wind of cord? There's no doubt in my mind that the layer of cord would remain in place for a long time, giving the belt strength in tension. I've made belts like this a few times, one just lately, but I used a rubber belt to start with. Could just as well be leather. The most difficult part would be coming up with a drum of sorts that the belt could be fixtured on, both to keep it aligned and to facilitate winding on the cord and smoothing over the rubber compound. My lathe is just barely adequate for a belt I'm coming up with right now, in terms of swing. Any belt longer than 26 inches and I'll need more swing.

Leather belts tend to be rather long things, do they not?

J Tiers
02-24-2013, 10:16 PM
Leather belts tend to be rather long things, do they not?

You are thinking of the weight-tensioned ones used on the farm.... usually have a twist in them. Might be 30 feet between pulleys

"We" would be using the lever-tensioned ones, which can be any size, flat, round/twisted, short, longer.....

My FIL has been using the same leather belt on his SB 9 model A (the full feeds model) for as long as his daughter and I have been married. It gets a lot of use, too. That belt is probably 25" on centers, if that.

It's hide-side in, and both it and the pulley are highly polished. never seen it slip.

andywander
02-24-2013, 10:18 PM
One reason for the long length on leather belts, I am told, is so that the belt will have sufficient weight to grip the pulleys.

Georgineer
02-25-2013, 08:22 AM
My father did his engineering apprenticeship in the Dockyard at Portsmouth in the 1920s and worked there as a turner and fitter for several years after that. He was a stickler for doing things right, and always mounted his drive belts 'shiny side out', which I presume was the way he was taught. The lathe I inherited from him has the belt 'shiny side out' and it still performs well after 45 years.

I suspect that any difference is marginal, and it won't make a lot of difference whichever way you do it.

George

J Tiers
02-25-2013, 09:28 AM
Most sources I have looked at suggest hair side in, and it works. It makes sense, as the smooth side will have more material area in contact. With a smooth and shiny pulley, as they tend to become, there is no advantage to having a "tooth" to the belt surface.

if the pulley is rough, there may be a reason to use the hair side out, the tooth of the belt and the rough surface may interlock.

My suspicion is that if you do use it shiny side out, the "non-shiny" side will fairly rapidly become 'shiny" in any case.....

atty
02-25-2013, 10:48 AM
Don't overlook the possibility of replacing the leather belt with an automotive timing belt, usually the 1" wide variety. Butt the ends together and lace with wire, or use the "alligator" type clips for leather belting. Operation is smooth and considerably more grip than leather.

alchymist
02-25-2013, 11:17 AM
Don't overlook the possibility of replacing the leather belt with an automotive timing belt, usually the 1" wide variety. Butt the ends together and lace with wire, or use the "alligator" type clips for leather belting. Operation is smooth and considerably more grip than leather.
Have read that a lot of people have had success splicing the serpentine style rubber belt for use on lathes with flat pulleys. Tried it myself without any success, both gluing with several different recommended adhesives, and lacing. Finally bit the bullet and pulled the spindle on my SB 9.

Forrest Addy
02-25-2013, 12:09 PM
Leather belt power transmission is a technology that may be obsolete but interesting in both a historical and engineering sense. There's plenty of info on the web.

Here's a nugget to start witn. The demand for buffalo hide coincided with the first big accelerando of the American Industrial Revolution. Can a case be made the near-extinction of the buffalo was caused by the demand for belting? The line shaft of a small water powered shop - a window sash and molding shop for example - might transmit 100 HP to power 40 machines and might need a quarter mile of belting to do it. Then there's harness, saddlery, shoes, etc. All in demand but nowhere near the demands made by post Civil War America. Cow and horse hides could not keep up with the demand for leather.

atty
02-26-2013, 01:14 AM
Have read that a lot of people have had success splicing the serpentine style rubber belt for use on lathes with flat pulleys. Tried it myself without any success, both gluing with several different recommended adhesives, and lacing. Finally bit the bullet and pulled the spindle on my SB 9.

I, too, went through the angst of adhesives on rubber belting. It just won't work for some reason, probably too much flex. The answer for me, at least temporarily, was a butt end laced with 18 ga. stranded copper wire, placing the holes about 1/2" from the splice. I think the holes were something like a #51 drill bit.

It is by no means the permanent solution as copper shows its wear pretty quickly, and you have to stop and re-lace. The beauty of copper was being able to solder the ends of the lace to the adjoining strand thereby completing the splice. Steel wire is, no doubt, the better way to go, but I haven't stopped long enough to explore how to anchor the ends of the splice. Plus, finding 18 ga. stranded superflex steel wire is another challenge entirely.

I was told guitar wire was a possibility, but alas, the binding problem persists, and I wouldn't think it would be flexible enough.

J Tiers
02-26-2013, 01:37 AM
That's what "Alligator" and "Clipper" lacing does very well..... splice belting, leather or rubber, whichever.

I have a "clipper" lacing gizmo of the right size from some toolbox I bought, but so far the old hammer-closed "Alligator" is holding up fine on my rubber/fiber composition belt.

rohart
02-26-2013, 06:40 PM
Quite right. This is what it looks like.

http://www.lathes.co.uk/flatbeltclips/

I've had to replace my clips once in twenty years on my small Lorch powered by a 1/2 HP 3-phase.

Before they're worn in, the clips drive my mad with their clickety-click as they pass round the pulleys. I wrap a little fabric based tape around the belt to cover the clip. It quietens it down, and lasts for several months.

Norm W
02-27-2013, 01:11 PM
I've been replacing belts with previously enjoyed conveyor belting. I cut the length and width that I need and use a clipper splice. I've had no problems with slippage and the material is already pre-stretched. It has transmitted enough power to a saw to bring an Allis-Chalmers "C" to it's knees. My Hendy lathe and Pulton horizontal mill are also running on conveyor belting.