Creating belt between two pulleys

gluebaby

Howdy, I'm sort of new to CAD, but I'm creating a rock tumbler for my sister. I have a pretty basic setup, and so far everything looks alright, and now I'm trying to create a belt between two pulleys. 



I've attached an image there. The pulleys look very gear-like because originally I was going to use gears, but I decided to go with a 3D printed timing belt instead. I've tried using curve patterns, manually sketching, etc, but can't figure out a way to generate a belt with teeth that match up with the two pulleys. The document is here: https://cad.onshape.com/documents/1c3f0bc7f43db3702e5291e2/w/16bfc5996eedb58af46b1170/e/4cca6effcc7d9333c9678bd0

If anyone knows how to do this, some tips would be great. Thanks!

MichaelPascoe

Welcome to Onshape!

Here is a great custom feature called Belt: 
https://forum.onshape.com/discussion/11475/updates-to-the-belt-custom-feature-official-v3

Measure distance: 
https://cad.onshape.com/documents/77baa8153589a7fc5f289829/v/b58988514272e25b1da139fb/e/d3174bf5315e6aafcb889367

Here is one way you could do this:
 https://cad.onshape.com/documents/de9a95acec26ad35a58f312e/w/7e798a8ee55283393b3b131d/e/3c614744d07a32b2ea9352b0

• Measure the parameter of the belt you need, thickness, and tooth information
• Create a sketch of a cylindrical belt. To dimension the circle by its parameter you will need to split it in two, and measure half. You probably know this already, but the belt needs to be cylindrical, it will flex to the shape you need.

robert_scott_jr_

Michael, what is the feature(s) accompanied with the calipers symbol? I couldn't find it in the toolbar. Is it a custom feature? - Never mind, I found it in the other document you included as a link in your post. Pretty tricky solution for the belt. Thank You. -  Scotty

Alex_Kempen

You could also try using my Belt Calculator FeatureScript to create the pulleys and belt together in one go. It's specialized for the types of belts I use in robotics - 3mm GT2 or 5mm HTD - but if you're okay with using either of those types, it can do everything you want it to do. It also calculates your belt center to center distance automatically (so your belt fits correctly), and it lets you add 3D printable pulleys which will work nicely with your chosen belt.

https://cad.onshape.com/documents/9cffa92db8b62219498f89af/w/06b332ccabc9d2e0aa0abf88/e/99672d1e329b38e647d90146