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Filament feed starts with the extruder, where the Drive Gears powered by the Extruder Stepper Motor grip and feed the filament. If any part of the filament path experiences a jam, the Drive Gears will be unable to feed the filament forward and will grind a groove in the filament. After fully grinding away the filament, this means that even if the jam is resolved the Drive Gears will are no longer be able to grip the filament, and you will need to manually apply forward pressure on the filament to get the Drive Gears to grip.
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Common causes for nozzle jams are insufficient purging between material swaps, leaving the Hotend preheated for long durations “cooking the filament” inside, or material impurities.
Troubleshooting Procedure
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