Dialing In a Reliable First Layer
A good first layer should look slightly pressed into the build surface, with adjacent lines touching but not overlapping heavily. When that does not happen, I work through these checks in order.
1. Clean the build plate
Wash the removable plate with warm water and dish soap, then dry it with a lint-free towel. Skin oils can cause adhesion problems even when the plate looks clean.
2. Check the nozzle height
Print a large, single-layer square and watch how each line is laid down:
| Appearance | Likely cause | Adjustment |
|---|---|---|
| Round lines with gaps | Nozzle too high | Lower the Z offset slightly |
| Transparent or rough lines | Nozzle too low | Raise the Z offset slightly |
| Flat lines touching evenly | Height looks good | Leave it alone |
Make changes in small increments—usually 0.02 mm at a time.
3. Slow down
For a troublesome model, I use a first-layer speed of around 20 mm/s. The extra time is insignificant compared with restarting a failed print.
4. Verify temperatures
Start with the filament manufacturer's suggested range. If adhesion is still weak, increasing the bed temperature by 5°C is a reasonable experiment.
Once a calibration square looks consistent from corner to corner, I save the settings as a printer profile rather than adjusting every model individually.