(way too little pulling force),
I'm in the early stages of designing my own extruder.
- geared down stepper motor
- spring-loaded lever to adjust the pressure
- mount for a rotary-encoder that meassures the filament being actually pulled in
- integrated compartment for a sponge to clean the filament
- use herringbone-gears
- mounting holes for a fan for the stepper motor
- low center of gravity (reduced stress in transport and backlash)
- allow ToM and RepMan hot-ende and allow both extruder mounts (I want to design this only once for both my printers)
- 3 point mouting (use 3 contact points to mount the extruder to a Thing-O-Matic z-stage as opposed to the flawed arc-like 2-point design of the default MK6-steptruder. Doesn't matter on a Repman.)
Originally I wanted to use 2 drive-grears to grip and pull the filament from both sides instead of clamping it between a drive-gear and a 608-bearing but I found that this would require a more complicated gear because the only stationary point on the lever is it's axis and that is not the axis of the intended second drive gear.
So that would require 2 more gears in a very small space.
Don't hold your breath. This will take me a while to get right but I'm working on it.
- post in BfB forum
- post in Makerbot group
- post in RepRap forum
- Design files on Thingiverse (coming soon)
- Photos (coming soon)
- Video (coming soon)
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