MPMD Improved Extruder Fix

A stand alone version of the extruder fix that comes with my top plate for flex filament.

The solution that comes with the stock extruder has a tendency to break after a while, which will make your PTFE tube come lose and ruin your print.

There is multiple solutions for the problem, I took an existing one and redesigned it so the tube when pulling would create more friction instead of pulling it open.