Makerbot Z18 TPU Extruder Mod

This part modifies the Makerbot Z18 Extruder + to allow you to print TPU and other flexible filaments.

This mod requires you to disassemble the Extruder and insert the piece as shown in the photo. Note that the flat surface is oriented to the top of the extruder. Once installed, you should insert a piece of regular filament into the extruder and make sure that moving the filament in and out will also make the extruder gear rotate. if it does not rotate then you will have to sand the piece a bit so the gear will bite the filament and rotate.

I have tested this mod with all types of TPU hardness and it has worked perfectly with all of them. I had to use an overhead spool holder since the TPU binds up in the PTFE tubes.