B'Struder: Universal Bowden 1.75mm Extruder

The B'Struder is an entirely new Bowden extruder design. It fits all common stepper motors, and all popular pinch gears. Variants are available for several common tube connections.

YOU PICK THE EXTRUDER HARDWARE! All you need is a few M3 screws/nuts, a suitable ~3/8" or ~10mm spring, and three 623 bearings.

Unlike most extruder designs, the B'Struder filament path runs entirely through the spring idler arm. This accomplishes two unique things:
1) Makes the filament path alignment very tolerant of different pinch gear diameters
2) Makes tension on the Bowden tube (due to filament pushing force) mildly assist pinch gear grip

This requires very specific geometry for the hinge, idler bearing, output fitting, and pinch gear contact point.

This is a new design, and feedback is welcome. But it's working great in my Delta so far. I'm running very aggressive retraction settings without any issues. Let me know how it works for you!

[UPDATE 11-13-15] Performance has been consistently awesome. I have two of them running with a lot of hours on each. The only real changes I have in the "to do" list are:
1) Widen filament inlet a bit
2) Add more fitting options (eg E3D pushfit insert, M4 tube back to the drive gear for flexibles) -- SEE REMIXES FOR MORE OPTIONS