belt tensioner for rostock max

by barnett, published

belt tensioner for rostock max by barnett May 11, 2013


My timing belts were scooting over and rubbing against the side of the idler bearings. It wears out the belts and can make a howling sound.

The solution is to make sure the bearing is level, but I was having a hard time simultaneously tightening the screw, holding the nut, applying upward pressure to the bearing and making it perfectly level.

Others have machined solutions similar to this, or used mirror clamps. I wanted to try something I could print.

Note: On my kit, the holes in the melamine above my idler bearings are the same size as the holes for the idler bearings. I think some kits have larger holes above where the idler bearings go. If you have the larger holes there, the brackets might need to be sized differently.

Recent Comments

view all

This is great, thanks

More from 3D Printer Parts

view more


Liked By

view all


Give a Shout Out

If you print this Thing and display it in public proudly give attribution by printing and displaying this tag. Print Thing Tag


Print 12 tensioner brackets and three spacers. Mine are ABS infill at 33% and they seem strong enough.

I replaced the 6-32 socket head screws holding the idler bearing with phillips head 6-32 1 3/4 inch screws because they are a bit longer. Same screws for the top brackets. The screws to pull the brackets together are 3/4 inch 6-32. My rostock max kit came with many extra washers and 6-32 lock nuts, so I'm using them.

This is great, thanks