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Don't pulley my leg

boygenius's picture

Don't pulley my leg (post #206061)

Hey guys and gals,


    I would like to know how to accurately measure a pulley (as in the flywheel of a compressor) in order to order a matching pulley for the motor. (the width and depth of the 'v' groove) Oh yeah, and the angle of the v.  How many different angles are there?





Uh oh.  I just realized that my handle is boygenius.  With this dummy of a question.  Well, I'm not really a genius, I'm more of a spontaneous savant.  Which I guess means that for short periods of time, I  -

I would see if McMaster Carr (post #206061, reply #1 of 3)

I would see if McMaster Carr has the information at

First off, if you have the (post #206061, reply #2 of 3)

First off, if you have the belt, or even a fragment of the old one, take it to a hardware store or auto parts place and they can measure it for you.

But the vast majority of industrial V belts have a standard angle.  It's only some automotive and special-use belts that are oddballs.

The "width" of the pulley, for the purposes of buying a new one, is the width of the matching belt, and that's measured across the outside surface of the belt.  In most cases, when the belt is properly fit to the pullley the top of the belt will be about 1/16 to 1/8 inch below the edges of the pulley.  So measure the distance between the sides of the existing pulley (on the inside, right at the top of the notch), and then pick the (slightly) next narrower belt size -- probably 5/8", 1/2", or 3/8".

Suggestion:  Beg, borrow, steal, or (as a last resort) buy a belt you judge to be the right width and then take it home and try it on the existing pulley.  It should fit as I say, with the top of the belt slightly snuggled down between the sides of the pulley.

After you get the pulley, the length of the belt is also measured around the outside surface. 

Of all the preposterous assumptions of humanity over humanity, nothing exceeds most of the criticisms made on the habits of the poor by the well-housed, well-warmed, and well-fed.  --Herman Melville

You want a pulley, go to a (post #206061, reply #3 of 3)

You want a pulley, go to a pulley store. That is, a place like Motion Industries or Applied Technologies.

The counter person will likly have a set of gauges that will identify the bely type ... is it "A", "V", "L", or whatever. Then he'll consult the catalog of somone like Browning, to see what is available.

Just as important, he'll be able to tell you if the pulley is manufacturer-specific. If so, you'll have to go to the maker for a replacement.