A little while back I got a Printerbot Jr V2 3D printer and have spent a little while trying to get it working. It turned out that it didn’t work too well out of the box. But now that I have figured out some of the ins and outs of 3D printing and messed with lots of parameters, I am able to consistently print items pretty well.
I ran into a number of problems with the extruder. I have been able to fix those by replacing the extruder assembly with an aluminum one, and by adding a cooling fan for the extruder stepper motor. The motor would overheat on long print and cause the filament to soften. That would cause it to jam up the extruder feeder gear.
I also figured out that my printer works better when I slow down the print speed. Since I normally don’t care much how fast it goes, that is fine with me.
I will post pictures of my extruder setup and solution to the overheating when I get a chance.