# Slipping Belts



## jschmidling (Nov 23, 2019)

About 25 years ago I bought a spray can of some stinky, tarry stuff that solved all the leather belt problems on my South
Bend lathe and was probably 95% full when lost in our fire.  I have no idea what it was (brand or functionally) and now I need some for the V belts on my mill drill.

All I can find now is stuff called "belt dressing" but it all seems to be auto related and intended to solve noise problem and has nothing to do with  belt traction.

Any idea what this stuff is now called or a link to an equivalent to what I had?

Thanks,

Jack


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## NortonDommi (Nov 23, 2019)

Hi Jack,
               The automotive stuff is fine.  I only know about the Wurth product but most automotive belt noise is caused by slippage not always a loose or damaged belt, sometimes the pulleys become highly polished and the belts glazed.  The spray on belt dressing conditions the belt and provides a very slightly tack that restores full function.
It is designed for V-belts.  Belt dressing for leather belts is different and most people mixed their own, Beeswax, Turkey oil, Neatsfoot oil and Rosin were common ingredients.


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## francist (Nov 23, 2019)

Sounds a little like pine tar. Readily available, especially if you know some baseball players, although not so much in an aerosol. I did find this...




I’ve also used rosin on V-belts to give them some extra traction. Available in solid form for tacking up the bows on string instruments (violin). Break it up into a powder, worked ok for me.

-frank


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## Video_man (Nov 23, 2019)

Some good information here:  https://www.smokstak.com/forum/showthread.php?t=44078.   One thing they mention is the use of molasses as a belt dressing, plus some source info on other stuff.


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## jschmidling (Nov 24, 2019)

francist said:


> I’ve also used rosin on V-belts to give them some extra traction. Available in solid form for tacking up the bows on string instruments (violin). Break it up into a powder, worked ok for me.



Actually, I tried that already.  I happen to play the violin and made my own rosin block from a tree in our pasture.  I found another chunk yesterday but was too lazy to melt and clean it properly and tried dissolving it in paint thinner but it didn't work very well.  After reading this, I tried acetone and it dissolved a little better and this seemed to work pretty well just brushing it on with an acid brush.

Thanks,

jack


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## mmcmdl (Nov 24, 2019)

If I remember correctly we used CRC belt dressing at my previous employer . We used it by the pallet loads moving cases of detergent up incline belts to the warehouse . When our line leaders used too much of it , we had to go out and grind the belts down back to the bare rubber .


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## Tozguy (Nov 24, 2019)

Just curious Jack, what is the problem with the V belts....noise...slippage...?
I've used the back tar based stuff and the automotive stuff but it just seemed like a temporary bandaid.
Modern quality V belts do not need dressing. At one point I just changed brands of belt and the noise went away.


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## RobertB (Nov 24, 2019)

Tozguy said:


> Modern quality V belts do not need dressing.


Yep, a good belt under proper tension should not need belt dressing. It will get you by with an old belt that has gotten hard and glazed until you can get a new one, but as Tozguy said this is just a temporary bandaid.


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## RJSakowski (Nov 24, 2019)

Early in life, I used to use belt dressing to reduce squealing and slippage.  It was my experience that, over time, the dressing was actually contributing to the problem.  It has been more than thirty years since I have used any belt dressing.  A rubber belt that has hardened or glazed should just be replaced.


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## Bob Korves (Nov 24, 2019)

Problems with V-belts can be caused by using the wrong type of belt.  There are subtle differences between types of belts, even if they show the same lengths and widths.  For example, automotive belts are different in design than belts designed for electric motors.  They are essentially not interchangeable, and if you do use the wrong type, that is when the belt slipping problems often arise.  Sometimes, for example, the inside diameter width of the belt is too narrow, and the belt is only bearing on that side, not on the angled flanks of the belt that are supposed to carry the loads.  Also, some belts have different angles than others and the pulley angle needs to match the belt angle to properly transfer power.  When in doubt, RTFM (read the f...... manual) and use what it says to use.  A Ford engine pulley is not the same as a Wards washing machine pulley is not the same as a South Bend lathe pulley (usually...)


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## projectnut (Nov 24, 2019)

In his first post on the subject the OP mentioned "leather belt problems".  My Seneca Falls machine also uses la leather belt, and like many other members I have tried various belt dressings over the years.  The original dressing I used came in a tube and was thick and sticky.  Unfortunately almost all the labeling was gone so I was unable to order more when I ran out.

After trying everything from soup to nuts I settled on 3M Super 77 Multipurpose spray adhesive.  I've been using it (sparingly) for over 10 years on my 1 1/4" leather belt.  It does a great job and doesn't seem to affect the belt.  I probably use it 3 or 4 times a year.  Having said that I don't over tighten the belt to the point the machine will be damaged in a crash.  I generally tighten it to the point that I can take a .125" deep cut off 6061 aluminum.  This seems to be tight enough that I can take .060 - .080 cuts on 1018 without slipping, but in the event of a crash the belt will still slip.

If the belting is worn or cracked to the point it needs replacement they can be purchased by the foot from McMaster.  They also sell several different styles of belt clips and lacings.


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## MrWhoopee (Nov 24, 2019)

I solved the slipping belt on my Heavy 10L by replacing it with an automotive serpentine belt, which I had to splice. It works so much better than a leather belt, the motor will stall before the belt slips.


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## benmychree (Nov 24, 2019)

Brand name is Cling Surface; black, tarry, smelly.  We use it at Sturgeon's mill on various flat belts to combat slippage.


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## Tozguy (Nov 24, 2019)

jschmidling said:


> now I need some for the V belts on my mill drill.


The leather belts were lost in a fire I think.


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## jschmidling (Nov 25, 2019)

Tozguy said:


> Just curious Jack, what is the problem with the V belts....noise...slippage...?



The trouble is trying to make a silk purse out of a sow's ear.

Among the treasures lost in our recent fire was a nice Jet Mill/Drill.

A friend donated an old Power King drill press to the cause and I have been trying to turn it into a mill/drill.  He happened to be a cabinet maker so the 3200 RPM motor didn't bother him much but it was pretty useless for metal work.

I replaced the motor with 1/2 HP 1700 RPM my wife found at a garage sale for $1 and it works great but is still too fast for my purposes.

I tried to re-create the pulley arrangement the Jet used and I think I may be missing something but it works well down to about 200 RPM but the belt/s slip when doing stuff like drilling large holes.

The 4 step transfer pulley I bought turns out to be a piece of Chinese junk but I made it work anyway.  The slippage problem might be due to the fact that the pulley looks too pretty to have any traction.  It has a mirror finish.  Sandblasting might fix that but I think the cure really is in the rosin.

I can not increase the belt tension beyond a certain point that causes the motor to rattle and clack and it's just not good practice anyway.  Furthermore, the slip is usuall in the other belt and there is even more reason not to stress that one.

So there you have my problem which may have been  solved with all the great ideas posted here.

Thanks,

Jack


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## NortonDommi (Nov 25, 2019)

Get an old small motorcycle engine and carve the crankcase off it, most of them are 6 speed AND keep a couple of the step pulleys then you will have a real frankenmill.


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## RobertB (Nov 25, 2019)

jschmidling said:


> View attachment 306494



If you are trying to run it as pictured, those belts are nowhere near tight enough. Because of the small diameter of the pulley, especially the intermediate one, you would be much better with cogged v belts. They will give you a better wrap on small pulleys. Even with that, such a small pulley is going to have a limited ability to keep a belt from slipping.


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## NortonDommi (Nov 25, 2019)

I thought the same as RobertB but thought it might be an optical illusion. Now I've got my reading glasses on Those belts look like they could be the wrong section as well.   They come in metric and Imperial and there are subtle differences

  Transmission factors have lots of information for download.  Here are some to look at.


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## RobertB (Nov 25, 2019)

NortonDommi said:


> Now I've got my reading glasses on Those belts look like they could be the wrong section as well.



Now that I have done the same thing(reading glasses on) you may be on to something there also. The one that you can see the best in the photo, upper intermediate pulley, the belt looks like it is seated far too deep in the groove.


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## jschmidling (Nov 25, 2019)

Sorry for the misleading photo.   I should have mentioned that I just threw it back together to take the pic.  The belts were tensioned only enough to show the layout.

As a point of interest, the machine came with a half inch belt and I switched to 3/8" for convenience.  I think I have at least ten belts so far.   Every time I change something I need a different belt and it has  become a joke around here.  

Honey.... guess what?  I need another belt.

js


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## hman (Nov 27, 2019)

Video_man said:


> Some good information here:  https://www.smokstak.com/forum/showthread.php?t=44078.   One thing they mention is the use of molasses as a belt dressing, plus some source info on other stuff.


A brazilian years ago, I took an R&R in Australia, including a couple days on a farm in the "outback."  My host had a huge circular saw, powered with a wide flat belt connected to a drum on his tractor.  The belt was not getting traction, so he got out his can of treacle.  Best I can tell, it's concentrated molasses.  It did the job nicely.  Thanks for tickling my memory!

... and a +1 on violin rosin.  I used to use it on the narrow V belt on my 9x20 lathe.  Just held the cake against the sides of the belt as it was running.


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## epanzella (Nov 27, 2019)

Try 5/8" belts. If the belt bottoms out in the pulley before the sides have full engagement it won't drive it's rated load.


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## Illinoyance (Dec 2, 2019)

I replaced the old leather belt on my South Bend 10K with synthetic.  The synthetic belt kept slipping.  Unable to find a source of belt dressing, I sprayed the contact side of the belt with 3M no. 77 spray adhesive.  It worked.

I agree with those who condemn the use of belt dressing on V belts.  On flat belts it is necessary.


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## mattthemuppet2 (Dec 3, 2019)

AX (cogged) belts will help a bit, but a variable speed motor like a treadmill DC motor will help a bunch more. However, at the end of the day you're doing the hardest work with the smallest driving pulleys so some slip is inevitable. Only real cure for that is a slower motor and bigger pulleys, or even better a poly-V belt set up. That's a hell of a lot of work though.


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