How to get the first layer right
The first layer needs to stick reliably without being compressed so much that geometry and material flow are distorted. If the nozzle is too far from the bed, the extrusion lines may not bond well. If it is too close, material can be pushed sideways or extrusion can be restricted. The correct setup depends on the printer and build surface, so use the printer manufacturer's calibration method rather than a universal numerical value.
Signs that the nozzle is too high
- rounded extrusion lines
- visible gaps between lines
- poor bed adhesion
- corners detach easily
- individual lines can be lifted
Signs that the nozzle is too low
- heavily flattened extrusion
- material pushed sideways
- rough first layer
- nozzle drags through material
- restricted flow
- stronger elephant foot
Check more than Z distance
Also check:
- clean build surface
- correct build-plate profile
- bed temperature
- material profile
- mesh bed levelling
- correct nozzle installation
Clean the build surface
Before changing calibration repeatedly, rule out: Follow the build-surface manufacturer's instructions.
- fingerprints
- dust
- glue residue
- unsuitable cleaning method
Different build plates can require different calibration
Different plates can have different thicknesses. The general principle is: changing the build surface may require a new first-layer calibration.
Do not calibrate by measuring one printed layer with calipers
A caliper reading is not a replacement for the printer-specific first-layer calibration process.