Pico-extruder

thingiverse

WARNING: my MK8-type drive gear is unreliable, stripping filament with retraction - adapt model for use with other drive gear types? This tiny, single printed piece bowden extruder is the smallest I have ever seen. I designed this because I wanted a very small, elegant extruder design that 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 are 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 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 filament_squeeze in scad file (default: 0.3mm). - I use 145 steps/mm with 1.8 degree stepper @ 1/16, extrusion multiplier 1.0