×Read this message from Erik, founder of YouMagine

Prusa i3 Y idler with belt tensioner

This part can be used to adjust belt tension on the y axis of printer

3D printer parts and enhancements

Creative Commons Attribution Share Alike

Commercial use is allowed, you must attribute the creator, you may remix this work and the remixed work should be made available under this license.

Learn more or download attribution tags


This part is a replacement of well known prusa i3 belt tensioner. One of image compare it.

With this part you can adjust belt tension in front of printer on the fly.

Suitable for threaded rods 10 mm in diameter. Distance between center of rods should be 20 mm. Stepper motor shaft is at height 29 mm.

A very simple way to install and remove. You need only screwdriver.
It is easy to adjust the position of the belt in a straight line.

How to assemble. Consult with provided image.

Insert part must slide slightly tight into main part to avoid backlash. Process printed parts surface with sandpaper if needed.

Materials and methods

- print all 5 parts using .stl attached
- 1x screw M4x12 ISO 7045
- 1x screw M3x16 ISO 7045
- 1x nut M4 ISO 4032
- 1x nut M3 ISO 4032
- 2x ball bearings MR84-ZZ (bore 3mm, OD 8mm, width 3mm)



Issues are used to track todos, bugs or requests. To get started, you could create an issue.


Mini sp logo grain 400x390Stamos added this to the 3D printer parts collection ago
Mini hal9000  1 stathious added this to the PRUSA collection ago
9fe29feda634ba702a3c525ce6d12ac3?default=blank&size=40Aleksei Bondarenko published this design ago