These are all the 3D models I have designed and printed for my plastic extruder. You can find the full tutorial on Instructables by clicking the link below:
https://www.instructables.com/Low-Cost-Plastic-Extruder-for-Fillament-Production/

All files are original unless specifically stated, in which case you can find a .txt document with attribution information and the original file location.

All parts were 3D printed on a modified Ender 3v2 in black Creality PLA. All parts were printed with a 0.6mm nozzle and no parts need supports (depending on how you orientate and slice them).