5 Dual Drive Bowden Extruders

I just uploaded a few bowden extruder designs that I’ve been testing.  They are all dual drive, direct drive, print in a single piece, and none of them have a quick release mechanism for the filament (I usually load and unload filament using gcode scripts).

The extruders will behave similarly, they all should provide plenty of extrusion force given a large enough motor, but the parts, form factor and cost differ.  See my Calibrating Extruder Grip post for info on configuring a new extruder.  Here’s some notes on the differences between the extruders:

Gearstruder J7

  • Uses one NEMA17 motor
  • Uses Printrbot Gearhead drive gears
  • Configurable fixed gap

Pros

  • Compact
  • Gears never need cleaning

Cons

  • Drive gears are about $25

 

Gearstruder J4

  • Uses one NEMA14 motor (preferably a large one)
  • Uses Printrbot Gearhead drive gears
  • Configurable fixed gap

Pros

  • Small
  • Gears never need cleaning

Cons

  • May not have enough torque for use with smaller nozzle diameters
  • Drive gears are about $25

 

Fostruder K4

  • Uses two NEMA14 motors
  • Uses knurled drive gears
  • Uses a M5 brass insert and a M5 threaded bowden coupler
  • Configurable gap or tension

Pros:

  • More compact than the Fostruder H4
  • Easy to install, knurled gears don’t need to be aligned

Cons:

  • Slightly lower resolution than the Fostruder H
  • Requires two motors (in series or parallel)
  • Knurled gears deform the filament

Fostruder H4

  • Uses two NEMA14 motors
  • Uses hobbed drive gears
  • Configurable gap or tension

Pros

  • Slightly better resolution than the Fostruder K

Cons

  • Slightly larger than the Fostruder K4
  • Hobbed drive gears may need cleaning if they fill with filament
  • Requires two motors (in series or parallel)

 

Quadstruder K7

  • Uses a NEMA17 Motor
  • Uses 4 drive gears, two as gears, two knurled gears for the filament
  • Uses a 5mm dowel pin and bearings

Pros:

  • Cheap and effective

Cons:

  • lots of parts
  • Knurled gears deform the filament

 

All of my extruder designs can be found in this collection.