Prusa i3 MK2 as a plotter

I wanted to label a CD and had only my Prusa i3 MK2 3D printer on hand. Since I didn't wanted to create a permanent installation I designed this part to simply slip over the extruder stepper motor. As it turned out I did not need a screw at all to clamp the holder to the stepper motor - it works fine only by friction. The pen is held in place by some holders which I hot glued on.

It uses two rubber bands to hold the pen. This works better than I expected since the rubber band gives enough flex (in z direction) so that the pen can move slightly up and down so that it is not pressed hard against the plotting surface and therefore damages nothing.

This was the first 3D part I designed and printed. Therefore it is not ultra high quality and contains some flaws like the unnecessary screw terminal. If a screw presses the semi-halfs together the whole part warps and is then crooked.

See it in action: https://www.youtube.com/watch?v=YQdHdr4Irz8

__Workflow to plot something:__

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