Remix of CharlStruder For E3D on Prusa Clone

I wanted to start printing with flexible filaments but did not have the money for a whole new compatible extruder so I decided to get some filament samples. The shop gave me some Flashforge TPU and TPE with the TPE a nice soft one.

This is what I ended up with:

I modified the extruder body to enclose the hobbed drive bolt and leave only a small area for the (smaller) tensioner bearing to press against the exposed filament. I also shortened the filament channel considerably between the hobbed drive bolt and the cooling tower to try minimize resistance and friction.

With a slightly higher temp than recommended I was able to print successfully with both TPU and TPE. However, with the TPE you do need an additional tension on the filament BEFORE the extruder but not a lot. That helps prevent the filament grabbing onto the hobbed bolt and wrapping around which then become a slight pain to remove.

The tension bearing I used is a 13mm (od) x 3mm (id) x 5mm (wide).

Just for fun I also changed my drive gears too but made the pinion gear on the stepper a clamp type instead of a set-screw type.