From a certain height up, the layers sit offset from the ones below, as if the part had split and moved. It's a layer shift, almost always mechanical.
It happens on any FDM printer. Setting names are Bambu Studio's: in Orca Slicer almost all have the same name, and PrusaSlicer or Cura usually have an equivalent.
Where do I start?
Two questions to sort out what to check. It's a guide, not a sure fix: every printer and every filament is different.
Check in this order
- The printerIf it printed fine yesterday and not today, it's almost never the profile. Check the plate, the nozzle and the room: printing at 15 °C is not the same as at 30 °C.
- The filamentA spool that has soaked up moisture gives strings, bubbles and brittle parts. Dry it before changing settings, and pick that filament's profile in the program.Filament pages
- The quick checksThe “First” list below: it's the fastest to check.Go to “First”
- The slicerOnly now, the settings below, in order. Change one thing, print a small test and compare. If you change three at once and it gets fixed, you won't know which one did it.Go to the settings
Check in this order
- The quick checksThe “First” list below: it's the fastest to check.Go to “First”
- The filamentA spool that has soaked up moisture gives strings, bubbles and brittle parts. Dry it before changing settings, and pick that filament's profile in the program.Filament pages
- The slicerOnly now, the settings below, in order. Change one thing, print a small test and compare. If you change three at once and it gets fixed, you won't know which one did it.Go to the settings
Check in this order
- The quick checksThe “First” list below: it's the fastest to check.Go to “First”
- The previewStep through the slicer preview layer by layer: that's where you spot missing supports and odd areas in this part.
- The slicerOnly now, the settings below, in order. Change one thing, print a small test and compare. If you change three at once and it gets fixed, you won't know which one did it.Go to the settings
First
- Loose belts: tighten X and Y. If you hear irregular clicking while printing, that's them.
- A knock: the nozzle hit something. Look for a bump on the part (infill that curled up, a loose piece of support) or whether the toolhead passed over another part on the plate.
- The printer on a table that vibrates or moves, or a cable or tube pulling on the toolhead at the end of its travel.
Then, in the slicer (in this order)
- Infill patternProcess › StrengthInfills that cross themselves (Grid, Triangles) leave little bumps where one line passes over another, and the nozzle knocks into them. Switch to one that doesn't cross, like Gyroid.
- Normal printing accelerationProcess › SpeedBambu suggests lowering speed and acceleration by 20 to 30% when a part shifts or collapses.
- Brim typeProcess › OthersA tall, thin part sways and the nozzle knocks it: a brim steadies it.
Tried everything and it's still the same? Calibrate your filament with the 8 tests, or write to us with a photo.