Gates belt idler-parametric

This is a belt idler for use with Gates toothed belts. Designed for our FIRST robotics team.


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The version here is for 15mm wide belt, the main body is 50mm diameter. Everything is parametric. The idler surface is crowned to help the belt stay centered. 
There is a flag to set that will print a small test to see if you have the OD on the bearing right. It should take a little force to insert the bearing. Print that first, adjust Bearing OD in the SCAD as needed.
The hardware stack is set up so that the nuts can be fully tightened without stressing the bearings (the spacer in the middle takes the force). 
 There is a bridging layer that needs to be cut out before using.
The hardware stack goes like this:
- Spin on a nut, put on a washer, then a bearing, then another washer, another nut. Tighten down. 
- Put the printed idler body on. 
- Follow up with another washer, a bearing, another washer and a nut. 
- Tighten the whole stack.

Materials and methods

- 5/16 or 8mm rod for axle
- 5/16 or 8mm nuts (3)
- washers (4)
- 608 (roller skate) bearings (2)



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C6bb61fe38c9e9027d707b0d0dccae45?default=blank&size=40BGham added this to the Interesting collection ago
7866cc7ff35e36c50a7971124ae67a92?default=blank&size=40Brent Bendes added this to the frc collection ago
4d3fab1519e6cafb99720c9a9e6f48b1?default=blank&size=40ymcc3d added this to the Gears etc collection ago
Mini photoJohn Ridley published this design ago