1.75mm Saturn Extruder - A compact planetary geared bowden extruder

I really liked the idea of alexspeller's Saturn Extruder, but was disappointed that he wasn't interested in making a 1.75mm version. While not required for 1.75mm filament, a geared extruder can be useful in certain instances. As such, I re-mixed the 3mm Saturn Extruder and made a few modifications.

The first modification is the obvious conversion to accept 1.75mm filament. One thing I had noticed as I was evaluating the original design is that it wouldn't be suitable for flexible filaments d