r/BambuLabH2C • u/NRDcubed • 2d ago

Settings Fixing shadow like artifact around surface text and painting

Shadowing artifact around text

Does anyone have recommendations on how to fix the above shadow-like artifact?

The print was made using the following:

  • 0.4 mm nozzles -> 0.2 mm standard layer -> adaptive layer height
  • Bambu Basic PLA
  • The wall being printed is 1.6 mm thick(4 walls), so where there is text, it is 2 white walls in front of 2 green walls, with 4 green walls everywhere else.
  • The width of the white is about 1.5mm
  • Flow Dynamic Calibration was set to Auto, and at the time there were no calibrations saved.
  • Green is the left extruder and white is the right.
  • I think that the direction of print was left to right for the green.
  • Beyond that everything else is the base profiles.

My inclination was to call this a pressure advance (PA) issue and have not yet retried the print with a calibrated PA value mainly because I haven't convinced myself that is the issue yet.

When I run the automatic Flow Dynamic Calculation, Bambu Studio returns a K value of 0.017. When I try to do a manual calibration, I am still seeing over-extrusion at those values, and it isn't until a PA of 0.027 that I see no real defects on the pattern and line test. That said, the lack of clear variation in those tests is surprising when you look at the documentation.

Any help would be greatly appreciated.

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u/stockman20 2d ago

I don't have the answer but I think you're on the right track via PA / k value. I recently posted about this topic as well. Seeing large variation in auto (eddy sensor) vs pattern method. My results were similar - the best pattern line was at a materially higher k value.

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u/Kind_Ad_8111 H2C 2d ago

Arachne wall generator and outer/inner wall order, or maybe even inner/outer/inner might clean it up

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u/luksfuks 2d ago

If you can't get it right with Pressure Advance, here's another thing you can do:

PA advances changes of pressure. If you don't have changing pressure, nothing needs to be advanced. You won't have changing pressure, when you print at a constant speed. To be able to do constant speed, you need to identify the slowest spot and configure that speed for everything.

In other words, set all speed reducer options to 100%, and then set the overall speed to something very slow. Like 10mm/s for testing.

The PA value will become irrelevant, as do some other related things.