Issue with Uneven Top Layer

Bambu Lab A Series Troubleshooting
1

Printer: Bambu Lab A1
Material: PETG
Issue Description:
When printing with PETG on my Bambu Lab A1, I experience uneven top layers when the “ironing” function is enabled. This issue only appears at heights of around 80mm and above. The top surface in the back left corner of the print bed remains smooth, but as the print moves toward the front right, the surface becomes increasingly uneven.

Observations:

  • The issue occurs consistently across multiple models.
  • The problem is only present when “ironing” is enabled.
  • Lower height prints (below ~80mm) do not seem to be affected.
  • The unevenness increases progressively from back-left to front-right.

Has anyone experienced similar issues or found a solution? Could this be related to bed leveling, airflow, or mechanical factors?

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2

“The problem is only present when “ironing” is enabled.”
From what I know ironing doesn’t just magically work properly just by turning it on, need to look into how to calibrate it and go through testing to figure out the proper settings. There is a bunch of guides and models for it on makerworld if you search thing like ironing calibration.