A bed mesh samples multiple points across the build surface and stores relative Z variation. Firmware can use this map to compensate for small deviations during the first layers.
How do you recognize it?
- Not a defect itself
- Bad measurements can cause local nozzle-distance errors
- Values may look implausible when probing is contaminated
Common causes
- Plate is not perfectly flat
- Nozzle/reference point is contaminated
- Plate is not seated correctly
- Probe calibration problem
What should you check first?
- Clean nozzle/reference surfaces before probing.
- Inspect the wiper when nozzle-based reference is used.
- Seat the build plate correctly and remeasure.