Pico-extruder

/!\ WARNING: my cheap MK8-type drive gear is unreliable, stripped filament with retraction - adapt model for use with other drive gear types?

Tiny, single printed piece bowden extruder; smallest I have seen.

I designed this because I wanted a very small, elegant extruder design which could be made from as few components and as quickly as possible.

This outperforms the generic all-metal extruder I had previously been using.

Parametric

Default settings for:
- 1.75mm filament
- Standard NEMA 17 stepper
- PC4-M6 push-fit bowden connector
- MR85zz bearings (pressing filament against drive gear, and under the drive gear, centering the printed part around stepper axis)

Parts list:
1x MK8 drive gear for 1.75mm filament
2x MR85zz ball bearing
2x M3x8mm or M3x10mm screw
1x M6 nut (square or hexagonal)
1x this printed part

Notes:
- Print with supports; you may want to try "support on build plate only" in Slic3r
- Drive pressure should be adequate; if not, adjust fi