I designed this robust extruder to be made by hand, with minimal components (most of which can be scavenged) and without using any 3D printed parts. This extruder features an all aluminum body, commercial 0.4mm nozzle, uses a diesel engine glow plug for the heater and can be adapted to fit almost any printer. For a list of materials and complete instructions, check out my article at MAKE: Projects. Demo video: http://www.youtube.com/watch?v=jOvjcN1uQ2s Time-lapse using OctoPrint: http://www.youtube.com/watch?v=jWqcX-dUo1o If you like this project and wan't to learn more about making things with 3D printers, laser engravers and other cool maker-tech, check out my new book "The Makerspace Workbench" from Maker Media! Don't forget to follow me on Twitter!