Bicycle Inner Tube Valve Cap as Filament Driver

I have Mendel with Adrian's geared extruder. Printing quality has always been uneven. I noticed that filament driver slips in spite of tight springs. Obviously driver teeths are not sharp enough.

I tried to make a new driver from bicycle inner tube valve cap like this.


Lathed first two M4 nut to fit inside the cap with power drill.



Clued all pieces together.


The final driver assembly


Much better printing quality

There is a reason we've been using hobbed bolts, it's not because they look fancy. It's because they are better. Mindblowing i know...

less surface area = bad
more surface area = good



Edited 1 time(s). Last edit at 10/30/2012 10:28AM by Asger.

Good to see some more experimentation. I've wondered how machined knurls would work...