Parametric pen holder for CNC

This is a pen holder for your CNC. There is no moving parts (hence no mechanical play), no spring needed as it's the ABS part that is acting as a spring.

It's designed to be sturdy in X and Y direction but flexible in Z. It can be preloaded with a an ajustable screw (as seen in the photo between the bottom leg and the extruded aluminium).

I preloaded mine at 5 grams, that's enough to write with my pen, and thanks to this preloading I only need to move my Z axis by 0.3mm up and down to writ