CustomDoug Report post Posted November 12, 2012 (edited) Hi, I'm going to be picking up a v-belt for an industrial cylinder arm machine with a servo that has a small pulley (50mm) installed. I have the motor mounted and sitting in what looks to be the perfect angle (the relationship between the foot pedal and servo arm linkage). When I put a flexible measuring tape around both pulleys (not down in the grooves) I get 52"... when I fit a length of twine around and "into" both pulleys, I get 49". I know there is plenty of adjustment to the motor but since these belts are readily available in all sizes [48,49,50,51,52,etc], and I like where everything is sitting now, which length would you get? I'm thinking 50" would be the best - but I'm not sure if the stated belt sizes are measured around the outside or inside? They look to be about 1/4" thick. thanks. Edited November 12, 2012 by CustomDoug Quote Share this post Link to post Share on other sites
The Major Report post Posted November 12, 2012 Pully 1 diameter x PI (3.14)/2 Pully 2 diameter x PI (3.14)/2 Plus length of pully 1 center to center of pully 2 multiply x 2. Add it all together is your length. Quote Share this post Link to post Share on other sites
CustomDoug Report post Posted November 12, 2012 Pully 1 diameter x PI (3.14)/2 Pully 2 diameter x PI (3.14)/2 Plus length of pully 1 center to center of pully 2 multiply x 2. Add it all together is your length. Wow, the scientific method ! ; ) That's good info. Sounds like the 52" (flexible tape wrapped around the top of both pulley's) was the correct number... and that those belts are measured around the outside diameter. Thanks. Quote Share this post Link to post Share on other sites
trekster Report post Posted November 14, 2012 The cross-sectional thickness of the belt determines the flat layout dimension that will fit over a given configuration. Here is a site that has a calculator on-line. Quote Share this post Link to post Share on other sites
