I am attempting to build a 3D printer using the Bear Upgrade for guidance.

In this moment, I am implementing the X-Axis. The X_end_idler consist in two parts, the idler and the belt tensioner, as you can see on the following pictures:

X end idler and tensioner

X end idler

Belt tensioner

The belt tensioner is inserted inside the idler. It is attached to the idler with two screws on the back part of the idler.

Back part of the idler

The tensioner holds a 2GT Idler Pulley as per the image: X Idler with tensioner, pulley and belt

So, here comes my question to anybody that has attempted to implement the Bear Upgrade:

How is the pulley attached to the tensioner?

The tensioner has a hole that crosses from side to side, but there is no space on the design where to fit a screw head nor a nut. I am a bit lost here and would like to know if there is a trick I can follow, before attempting to modify the design.

Here I attach the link to the pieces: Bear_extruder_and_x_axis


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    $\begingroup$ What about a 3 mm axle/shaft, as it is enclosed it will not fall out. You could even cut the head of a screw and use the threads. $\endgroup$ – 0scar Jan 30 at 20:29
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    $\begingroup$ Or maybe a roll/spring-pin? $\endgroup$ – Trish Jan 30 at 22:06

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