Cosmetic Issue

How to Fix Over-Extrusion (Blobby / Too Much Material)

Step-by-step fix for over-extrusion (blobby / too much material) on Bambu Lab printers including X1C, H2D, P1S, and A1.

How do I fix over-extrusion (blobby / too much material)?

1
Reduce flow ratio by 2–5% (e.g., 0.98 to 0.94). Print a single-wall calibration cube and measure — if wall thickness exceeds nozzle diameter, flow is too high.
Setting: Flow ratio
2
Check that the correct nozzle size is selected in the slicer. If you have a 0.4mm nozzle but the slicer is set to 0.6mm, it will massively over-extrude.
3
Lower nozzle temperature by 5–10°C. Over-heated filament flows more freely and expands more at the nozzle tip, causing excess material deposition.
Setting: others.nozzle.nozzleTemp

Pro tip: Select "Good Cosmetics" above — the recommended settings help identify and fix flow-related surface quality issues.

Related Print Issues

Uneven First Layer Stringing / Oozing Visible Layer Lines Elephant Foot (First Layer Bulge)Warping / Curling / Lifting

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