Extruder motor jam
Today I had a print failure when the extruder stopped extruding. On investigation something was jamming the extruder stepper motor. This time it was not just a filament jam. I opened the side door and removed the remaining filament, then forced the motor to rotate with a screwdriver working against the bondtech gear. There was a click, then everything seems to be normal again.
I did notice red deposits around the drive gears for the Bondtech. I'm assuming it was rust from wear. I lubed the gears (sparingly!) before I put things back together.
Sorry, no pictures. Does anyone have ideas as to what might be going on? Should I order new Bondtech gears? This printer has had many hours of use over the last 22 months.
RE: Extruder motor jam
Rust on the gears seems unlikely. More likely something jammed in behind where you can’t see. But forcing the gears with a screwdriver is a bit scary.
I think I’d plan a maintenance day and tear down the extruder for a good cleaning and proper lubrication. The idler gear can get filled with filament dust over time and lock up on you as well so don’t overlook that.
Best to have a few of the common spare parts on hand, ’just in case.’ inspect the BondTech gears to determine if you think they need replacing as they tend to not be cheap. Good luck.
Cheers
RE: Extruder motor jam
Well, it's happened two more times. The symptoms are that the extruder motor just stops. In the latest instance it appears that it stopped for a while, then restarted, then stopped for good. The idler is free. I'm now suspecting that the extruder motor itself is the problem. It shouldn't be a heat issue. I've printed with ABS quite a lot, but the most recent problem happened when I was printing with PETg. So everything is just out in open air.
I'll take the extruder apart tomorrow and see what I can see. In both previous instances, I just forced the extruder motor to rotate a little bit and everything started working again. It could be the motor driver I suppose.
Any suggestions are welcome.
RE: Extruder motor jam
I took the extruder motor apart and found a bad bearing. The printer now has a new extruder motor, hopefully this will be my last post on this thread.
Prusa is out of stock of this particular motor. Luckily I found one in the US from partsbuilt.com. No affiliation. It came in just a few days and it is an exact replacement.
RE: Extruder motor jam
I know I said that I wouldn't post again in this thread, but I just have to.
Surface quality of my prints have been outstanding since I replaced the extruder motor. The old motor must have been affecting prints for some time. Who'd know?
I found a replacement bearing on Aliexpress, so now I have a spare motor. The bearing was very inexpensive, although it took a few weeks to get here from China.
RE: Extruder motor jam
Good to hear all is working well for you.
Cheers.