How do you calculate the length of a belt around two pulleys? Lets say that the larger pulley has a radius of 20" and the smaller has a radius of 6" and distance between the center of the pulleys in 56".
Lets assume that belt has a thickness of 0.
I thought that a good way to estimate this would be to create a right triangle by moving the line between the center of each pulley up to the tip of the smaller pulley. This would create a right triangle with the sides being the centerline, the radius of the larger pulley minus the radius of the smaller pulley and the distance between the highest point on the two pulleys. Then I could calculate the distance between the pulleys using the pythagorean theorem, double it and add half of the circumference of the two pulleys.
However, this seems to assume that the belt cuts through the pulley, when in actuality the belt goes around more than half of the larger pulley. I suspect that the above method is a good estimation, but how could I calculate the length of the belt to a higher degree of accuracy?
(I'm sorry if the above solution is convoluted, its pretty difficult to describe these types of math problems without a picture
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