In this video I will take apart and attempt to repair my sister’s generic 3D pen that suddenly stopped working. She was very disappointed as the device only lasted for three months before it would no longer uptake the plastic ABS filament. I was surprised how easy the pen was to take apart. Everything was held together by 5 screws and a few clips. Thank goodness I did not have to cut through any glue! It did not take me very long to find the problem. The feed mechanism utilized a very intricate gearbox that had already worn down. One of the gears was so worn that it no longer made contact with the others and therefore was not effectively driving the motor heat. Unfortunately, with my skill set, there was no easy way to fix this problem. The only thing I can do with the pen now is keep it around for spare parts and maybe use it for a project in the future.