Initial Layer Texture problems

I am having issues where the initial layer is no longer smashing the filament into the Textured PEI plate and giving that clean surface texture. Instead, I am seeing layer lines. I tried getting pics, but its not really showing up.

Were there recent changes in the last few months in either Bambu Studio or the firmware that would have caused this?

I saw this thread: Irritating under-extrusion problem after FW update? Try this

and tried a factory reset, but it did not change the bed layer finish. I’m not really getting adhesion issues, either.

I can change the initial layer height in the slicer, but I was curious why this is happening now.

The issue you’re experiencing with the first layer not embedding into the textured PEI plate could stem from several factors. Here’s a breakdown of potential causes and solutions:

  1. Recent Firmware or Software Changes

    Firmware or slicer updates can occasionally alter default settings for initial layer height, flow rate, or Z-offset.
    If this started happening after an update, verify if there were changes to:
    Initial Layer Height: Check if the slicer’s default value has been modified.
    Z-offset Adjustments: Some firmware updates might recalibrate Z-offset logic.
    Solution: Manually recalibrate the Z-offset (see below).

  2. Z-Offset Calibration

    If the nozzle is slightly too high, the filament won’t properly “squish” into the plate, resulting in visible layer lines.
    Solution:
    Run a bed leveling calibration.
    Fine-tune the Z-offset during a print:
    Lower the Z-offset incrementally (e.g., -0.02 mm at a time) while the printer lays down the first layer.

  3. Slicer Settings

    Some slicer profiles may have different initial layer parameters:
    Initial Layer Height: Could have been changed in Bambu Studio.
    Initial Flow Rate: Lower flow rates can result in poor adhesion and finish.
    Solution:
    Check your slicer profile settings.
    Ensure the Initial Layer Height matches the desired texture effect (e.g., 0.2 mm or less for textured finishes).
    Increase the Initial Layer Flow to around 105–110% to ensure proper adhesion.

  4. PEI Plate Condition

    Over time, textured PEI plates can accumulate residue or wear down, impacting adhesion and texture transfer.
    Solution:
    Clean the PEI plate with isopropyl alcohol or soap and water to remove oils or residues.
    If wear is visible, consider flipping or replacing the plate.

  5. Environmental Factors

    Changes in ambient temperature or humidity can affect how filament behaves.
    Solution: Preheat the bed and nozzle adequately and ensure the filament is dry.

  6. Extruder or Flow Issues

    Under-extrusion could also prevent the initial layer from filling and adhering properly.
    Solution:
    Perform a flow rate calibration to ensure consistent extrusion.
    Check for any partial clogs or wear in the extruder and nozzle.

If the issue persists despite adjustments, it might be worth reverting to an earlier firmware version or contacting Bambu Lab support for additional troubleshooting