Under-extrusion: gaps in walls and weak layers

Less plastic comes out than needed: thin walls, gaps between lines and sparse infill.

Signs

• Gaps between lines
• Top surfaces with holes
• Layers that snap
• Extruder clicking or skipping

Check in this order

1. Dry the filament.
2. Check for a clogged nozzle and clean dust from the extruder gear.
3. Raise the temperature 5–10 °C.
4. Lower the speed: stay under the filament’s maximum volumetric flow.
5. Calibrate flow ratio.
6. Make sure the spool turns freely.

Common mistakes

• Only raising temperature without checking the nozzle
• Speeds above the hotend’s limit
• Ignoring dust in the extruder