Layer shift: when layers move sideways
are explained briefly when you hover over or tap them.
With a layer shift, part of the print is offset sideways, as if someone had pushed the upper layers over. The printer has lost its orientation: it believes it is at a certain position but is in reality a few millimetres off. All following layers are then printed offset.
How do you recognise a layer shift?
- A clear step in the print, from which everything is shifted
- Offset usually in one direction only (X or Y)
- Often accompanied by a loud crack or knock during the print
A single, strong offset points to a collision. Many small offsets suggest a mechanical problem instead.
The causes, sorted by frequency
1. The nozzle hits the print
If a corner has curled upwards through warping or a piece of material sticks out, the nozzle can catch on it. The motor loses steps as a result.
Solution: Prevent warping, enable Z hop in the slicer (the nozzle lifts briefly during travel moves) and avoid travel moves over parts that have already been printed.
2. Loose or incorrectly tensioned belts
The belts transmit the motion of the motors. If they are too loose, they skip over the teeth. If they are too tight, the mechanics become stiff.
Solution: Check the belt tension according to the manufacturer’s specification. On CoreXY printers, both belts must be tensioned equally, otherwise skewed parts also result. Many manufacturers describe how to check the tension, and some printers measure it themselves.
3. Loose pulleys on the motors
The small pulley on the motor shaft is fastened with a grub screw. If it has come loose, the pulley slips on the shaft.
Solution: Check and tighten the grub screws. The screw should sit on the flat side of the shaft.
4. Speed or acceleration too high
If speed or acceleration is raised in the slicer beyond the printer’s limits, the motors cannot keep up.
Solution: Use manufacturer profiles or reduce the values.
5. Stiff axes or obstacles
A cable that catches, dirty guides or an object in the travel path slow the movement.
Solution: Move the axes by hand with the printer switched off. They should run smoothly and without resistance. Clean and lubricate the guides according to the manufacturer’s specification.
6. Vibrations
A knock against the table or an unsteady surface can trigger an offset, especially on bed slingers.
Solution: Use a stable, level surface.
Quick checklist
- Did the nozzle catch on the print? Then check warping and Z hop.
- Are the belts tensioned correctly, evenly on CoreXY?
- Are the pulleys seated firmly on the motor shafts?
- Do the axes run easily and without obstacles?
- Were speed or acceleration increased?
Many current printers detect collisions and lost steps themselves and pause the print. It is therefore always worth looking at the printer’s error message.