pulley size

[brightspark]

I'm after a 87mm pulley or 3 and a half inch across. ad says pitch diameter and outside diameter which is it of ???

 

[bigegg]

For the 6mm difference, it *probably* won't matter.

 

[brightspark]

whats the pitch diameter??

 

[roofman]

the V section i think..

 

[8ob]

whats the pitch diameter??

Measured at the bottom of the V so would depend on what section belt is being used.

Bob

 

[brightspark]

its just a 87mm across outside diameter a section required so no need to tell them the p[itch /??

 

[rtbcomp]

http://www.gizmology.net/pulleysbelts.htm

"The pitch diameter of a pulley is not the outside diameter. Or the inside diameter. In fact, the pitch diameter is very difficult to measure directly. If you cut a belt and look at the end, you'll see a row of fibers near the outside surface. This is the tension carrying part of the belt; the rest of the belt exists only to carry the forces from the pulley to and from these fibers. The pitch diameter of any pulley is measured at these fibers. If you think about this for a moment, you'll see that the pitch diameter of a pulley depends not just on the pulley itself, but on the width of the belt. If you put a B series belt on an A series pulley, it will ride higher than usual, increasing the effective pitch diameter."

 

[brightspark]

thanks il just give them the od of pulley then

 

[Sarto]

If you look inside this catalog, you will find all the pulleys dimensions.
They depend on the size of the belt you need.

http://www.poggispa.com/pict/cataloghi/EN/080_V-belts drives.pdf

Hope this help.



Sart0