Heat creep occurs when the cold side of the hotend becomes too warm. Filament softens, swells or buckles before it reaches the melt zone and can eventually jam the feed path.
How do you recognize it?
- Print starts normally and extrusion degrades later
- Extruder clicking or grinding
- PLA problems inside a hot enclosure
- Filament is swollen after removal
Common causes
- Warm chamber with PLA
- Hotend fan or airflow problem
- Dirty heatsink
- Excessive temperature or unfavorable retraction
What should you check first?
- Open or ventilate the enclosure for PLA when appropriate.
- Check the hotend fan and airflow.
- Inspect the heatbreak for a jam.
- Avoid unnecessarily high nozzle temperature.