First Layer Adhesion: A Complete Troubleshooting Guide
Step 1: bed level and nozzle gap
Print a single-layer first-layer test square. The lines should touch each other slightly with no gaps, and the surface should look smooth and even. Gaps mean the nozzle is too high; ridges or transparent lines mean it is too low.
Step 2: bed surface for your material
| Material | Best surface | Helper |
|---|---|---|
| PLA | PEI smooth or textured | None usually needed |
| PETG | PEI textured or glass | Glue stick to prevent over-adhesion |
| ABS / ASA | Glass | ABS slurry or glue stick |
| TPU | PEI | Glue stick |
| Nylon | Garolite or PEI | Glue stick |
| PC | PEI | Glue stick |
Step 3: cleanliness
Skin oils kill bed adhesion. Wipe the bed with isopropyl alcohol before every print. For PEI, a deeper clean with dish soap and warm water once a week restores the grip.
Step 4: first-layer settings
- Speed: 15 to 25 mm/s for the first layer
- Bed temp: top of the material's range, not the bottom
- Layer fan: off for the first 1 to 3 layers
- Initial layer height: 0.2 to 0.24 mm (chunky)
- Initial line width: 0.5 mm or higher
Common problems mapped to fixes
- Corner lifts mid-print: warping, see the warping fix article
- Lines do not touch: nozzle too high, lower 0.05 mm
- Plastic squished, no extrusion: nozzle too low
- First layer rough: bed dirty or wet filament
- Print rips off bed surface mid-print: bed temp dropped, surface contaminated