Nylon Extruder from soldering station
Of course, the machine described in the previous post was never meant to have a sole purpose of pizza printing (which it admittedly does badly) but to become a repstrap machine so I can build a sweet Mendel. Next step after a cartesian robot is the plastic extruder. Although other people have tried to use a soldering iron (with limited success) we chose that approach nevertheless. Since isolated heating wire appears to be hard to come by (except for the makerbot store) and we had a spare soldering station lying around. Our first tests seem promising:
Critical issues are the steep thermal decline you need from the guiding tube to the heated nozzle. As soon as you drop pressure in putting the nylon through, the plastic pops out on top of the heated nozzle. Next up are a guiding tube from peak (or perhaps some ceramic material) and the steppermotor drive for automatic feeding.
BTW.. the reason we use nylon, is that you can buy it in a normal DIY hardware store. It is normally used for pulling wires trough tubes or unblocking drainage. ABS wire is still pretty expensive everywhere, especially for this kind of testing you’re not going to buy 3 kg…