How to Fix 3D Print Layer Shifting
Everything printed above a certain point is shifted sideways relative to the layers below it, as if the whole top half slid over.
Common causes
Loose or slipping belt
A belt that isn't tensioned enough will slip on its pulley teeth under load, losing position.
Loose pulley grub screws
If a pulley isn't seated firmly on the motor shaft's flat, it can spin in place without moving the belt.
Missed steps from excessive speed or acceleration
Pushing the print head faster than the stepper motor can reliably follow causes it to lose steps.
A physical obstruction
Detached spaghetti from a partially failed print, or a snagged cable, can physically block the gantry mid-move.
How to fix it
Check and tighten belts
A properly tensioned belt should feel taut and give a consistent "twang" when plucked, not feel floppy.
Re-seat and tighten pulley grub screws
Make sure the screw lands on the shaft's flat spot, not just the round part of the shaft.
Lower print speed and acceleration
Especially on sharp corners — dial these back in your slicer if shifting happens at the same feature repeatedly.
Inspect the gantry and rails
Clean off any debris and check nothing is catching as the head moves through its full range.
Still stuck?
ForgePrint diagnoses the exact cause for your printer and filament — describe it, or just upload a photo.