Now it won't extrude at all, not even any sign off plastic bubbling when it gets up to temperature. The 2mm brass tube is clear. What do I do now?

MakerGear support figured out the issue for me. My son had changed the extrude speed in Pronterface to 5mm/min (from 100) so it hadn't really locked up, it was just turning really really slowly!

No

Same problem happened again tonight. But now I can't get it running at all. When I power up the printer, the extruder is free to turn by hand. As soon as I ask it to extrude or reverse there is a small clunk from the motor and then it locks up until I reset the printer again. When it's locked up you...

Remember if the motor is powered then it wont turn by hand and seem locked up. Yes I checked that. With the printer powered off, the motor turned freely by hand. Doing that might be what "fixed" it and freed up the gearbox. Both times this has happended now, it is when we have gone to change out th...

Thanks, I will try disassembling the gearbox tonight to see if that is the issue.

Well that fix didn't last long. It's stopped working again. Turning off and then back on again and then heating up the hot end, then trying to extrude just results in a small clunk from the motor and then nothing. It's like the gearbox is locking up?

I fiddled around and reseated some connectors and now it's working again.

Toby wrote:When you disassemble, is the extruder still at temp? By default the Marlin firmware won't allow the extruder motor to run if the temp is not up to a certain amount.

Yes it was still at temp. There was no warning message about cold extrusion.

My son went to change out the filament last night after a successful print and the extruder refused to back out the filament. Now I can't get the extruder motor to turn at all. Hot end is up to temperature and Prontoface says its sending the command to extrude 5mm. I disassembled the head to be sure...