I have a EckerTech RepRap printer that I just built. After some problems getting the printer working, I had everything running fine yesterday and printed for a total of 11 hours, four different prints, but on the last print, the extruder started giving me trouble.

Early in the print, it stopped extruding. The hobbed bolt had chewed out the side of the filament. I cleaned the nozzle, cleaned the hobbed bolt, and started again but it only printed 6" to 12" before it plugged up again. I cleaned everything and tried again many times. I have tried higher hot end temp (up to 290C), lower temp (230), lower feedrate, lower flow rate, each time cleaning in between, and it does the same thing every time. The printed trace starts to get narrower and then the filament strips in the extruder drive.

The nozzle is 0.45mm but I don't have a .45mm drill bit and can't get one until Monday. I use the cleaning wire that came with the kit (0.43mm) but it isn't long enough to pass all the way through the nozzle. The extruded filament (when it IS extruding) is 0.63mm (0.025")

I can't, for the life of me, figure out why it quit working and started plugging! It is SO consistent in printing 6" to 12" and then chewing up the filament!

HELP!!!!