1.75mm Saturn Extruder - A compact planetary geared bowden extruder

thingiverse

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 due to the large gap between the hobbed gear and the constrained filament path. As such, I separated the filament guide from the top case and lengthened it in order to reduce the gap in an effort to hopefully allow for flexible filaments. Finally, I modified the gear ratio to be 4.5:1 since 1.75mm filament needs a little more speed than 5:1 can provide. I'll update this thing as required once I get the extruder printed and working. ********** UPDATE ******** I had lots of issues with the gears going sideways and jamming up the feeder. I ended up giving up and going with the Dragon Geared Extruder (https://www.thingiverse.com/thing:2172854) as it's much simpler and has a 3:1 ratio, which is exactly what I wanted. I'll leave this posted for anyone that wants to mess with it, but beware that it won't work in it's current state.