Bambu Lab: layer shifts and automatic recovery from step loss

Symptom

From a certain height the layers of the part are shifted to one side, or the part comes out stepped or skewed because the printer lost its position on an axis during the print.

Likely causes, from most to least likely

1. Something blocks the toolhead: filament piled up at the purge chute during filament changes, a damaged toolhead cable chain (X1, P1, P2 and H2 series) or badly routed tubes and cables (A series).
2. The nozzle hits the part: a very sticky filament such as PETG clinging to the nozzle, or a part that has warped.
3. Speed too high, for example switching to Ludicrous mode from the screen mid-print, especially if the carbon rods have friction.

Checks to tell which one it is

• Move the X and Y axes back and forth and look for anything blocking them; if you have the recording, review it.
• Check whether the nozzle touches the part or the part has warped.
• Remember whether you changed the speed during the print.

Before you start

Before taking anything apart, cleaning or adjusting it, switch the printer off and unplug it, unless a step says otherwise, and do not touch the nozzle, the heater block or the bed until they have cooled down. If in any doubt about electricity, heat or moving parts, stop and ask a professional.

Step-by-step fix

1. Clear whatever blocks the toolhead

   Check that nothing blocks the X and Y axes: filament at the purge chute, the toolhead cable chain (X1, P1, P2 and H2) or the tubes and cables (A series).

   Check: The toolhead moves freely over its whole travel.

   If that does not fix it: Stop the nozzle from hitting the part.

2. Stop the nozzle from hitting the part

   With very sticky filaments (such as PETG Basic), dry it or enable the prime tower. Use the right bed temperature on the Textured PEI Plate so the part does not warp and, with engineering materials such as PAHT-CF, the Smooth PEI Plate with an even layer of glue.

   Check: The nozzle no longer touches the part.

   If that does not fix it: Enable auto-recovery from step loss.

3. Enable auto-recovery from step loss

   Enable «Auto-recovery from step loss»: on the X1, in Control › Print options; on the A series, P2S, X2D and H2 series, in Settings › Print options; on the P1, from Bambu Studio. If the motor detects lost steps, the printer returns to its position and carries on printing.

   Check: Layers stop shifting.

   If that does not fix it: Do not raise the speed mid-print.

4. Speed and rods

   Do not switch to a higher speed (Ludicrous) while printing. On the X1 and P1, clean the carbon rods so they do not drag.

   Check: The part comes out without steps.

   If that does not fix it: If it continues, contact Bambu Lab support with the video and the printer logs.

Prevention

• Keep the purge chute clean and the tubes and cables tidy.
• Clean the X1 and P1 carbon rods as part of maintenance.
• Keep auto-recovery from step loss enabled.

Still not fixed?

Tell usi3d's AI about your case: choose your printer, describe what you see and add photos if you like. It proposes checks step by step, with their sources.

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Printers it applies to

Bambu Lab's FDM printers: A1, A1 mini, A2L, H2C, H2D, H2D Pro, H2S, P1P, P1S, P2S, X1, X1 Carbon, X1E and X2D.

Official sources

This guide summarises the official documentation linked here:

• Layer Shift: Causes and Solutions · Bambu Lab