New motors, new nozzle
Sorry things have been a little slow around here, but we are getting back into the swing of things. So over the past 3 weeks we have used three different motors to run the screw. The first one did not have enough torque and could barely run the system. We replaced this one with one from a car window motor. That thing had plenty of torque and was fast. But our power supply could not handle the current and it almost ran to fast for the filament to cool. Note, this motor will work great when we are able to make filament at higher speeds. Finally, we are using a powerful (about 500 in oz of torque) motor from RobotShop.com (great site for random robotic electronics and parts). This motor runs at 15RPMs (about the same speed as our first one) and runs great. It has the torque to run the system and the power supply can handle it. So we fix the motor issue and we run into the next one. We can get the filament to come out but its stringy or globby. We fix this by making a new nozzle and heat that nozzle at a constant rate. The issue with the thin filament may be due to the fact that the nozzle is cooler than the melting temp of the filament.
This filament was made using the third motor. You can see some globs of plastic.