3, FDM — Grinding Filament
What’s the issue?
Grinding or stripped filament can happen at any point of the printing, and with any filament, it may cause printing stops, printing nothing in mid-print, or other issues.
Possible causes
—Tangled Filament
—Nozzle Jammed
—Printing Too Fast
—Extruder Issues
Troubleshooting tips
—Not Feeding
If the filament has just started not to feed because of grinding, re-feed the filament again. If the filament grinds repeatedly, check for other causes.
Push the filament through
Push the filament with gentle pressure to help it through the extruder, until it can feed smoothly again.
Re-feed the filament
In some cases, you’ll need to remove and replace the filament and then feed it back. Once the filament has been removed, cut the filament below the grinding and then feed it back into the extruder.
—Tangled Filament
If the filament is tangled that can not move, the extruder will press on the same point of the filament, which can cause grinding.
Untangle the filament
Check if the filament is feeding smoothly. For example, check that the spool is winding neat and the filament is not overlapping, or there is no obstacle from the spool to the extruder.
—Nozzle Jammed
The filament can not feed well because of the nozzle is jammed and cause a grinding problem.
Go to the Nozzle Jammed section for more details on troubleshooting the issue.
Check the nozzle temperature
If you have just fed a new filament as the issue started, double-check that you have the right nozzle temperature.
—High Retract Speed
If the retract speed is too high, or you are trying to retract far too much filament, it may put excessive pressure on the extruder and cause grinding.
Adjust retract speed
Try reducing your retract speed by 50% to see if the problem goes away. If so, the retract speed may be part of the problem.
—Printing Too Fast
When printing too fast, it may put excessive pressure on the extruder and cause grinding.
Adjust printing speed
Try decreasing the printing speed by 50% to see if the filament grinding goes away.
Extruder Issues
Extruder takes a very important part in grinding filament. If the extruder is not working in good conditions, it strips the filament.
Clean the extruding gear
If grinding happens, it is possible that some filament shavings are left on the extruding gear in the extruder. It can lead to more slipping or grinding, in this case, the extruding gear should have a nice clean.
If the extruder tensioner is too tight, it may cause grinding. Lose the tensioner a little bit and make sure there is no slippage of the filament while extruding.
Cool down the extruder
Extruder overheat can soften and deform the filament that causing grinding. The extruder gets overheated when working abnormally or at a high ambient temperature. For direct feed printers, in which the extruder is close to the nozzle, nozzle temperature can pass to the extruder easily. The retracting filament can pass heat to the extruder as well and add a fan to help cool the extruder.
