Layer Shifts

Layer shifting happens when the printer loses its expected X or Y position during the print. Unlike ordinary surface imperfections, the whole model suddenly moves sideways. Start by checking the printer's belts. They should be properly tensioned and should not feel extremely loose. Inspect pulleys and belt attachment points. A pulley that slips on a motor shaft can cause repeated shifts. Move the print head and bed by hand while the printer is switched off. Movement should be smooth without obvious sticking or obstruction. Check that cables, filament tubes and spool holders cannot catch on moving components. Very aggressive printing speeds and acceleration can also cause missed motor steps. If shifts happen during fast prints, reduce speed and acceleration. Make sure the model itself has not detached from the bed. Sometimes what appears to be a layer shift is actually the entire print moving. If shifts repeatedly occur at approximately the same height, inspect the machine carefully for a mechanical obstruction at that position. Common causes: loose belts, slipping pulleys, excessive acceleration, mechanical obstruction, print detachment.