Printrbot Simple Metal Reverse Bowden (Feed Tube)

Reverse bowden setups help relieve tension on the extruder by the filament by making the length of filament between the spool and extruder constant. This was designed to printed in PETG but any strong and moderately flexible plastic should work. I did bend the flaps on the aluminum spool rack to be closer to 90 degrees to the top of the rack.

Edit (12/20/2016): updated extruder piece to fit better, angled filament piece to provide a more natural path for the filament, and updated bar to make