Streak in smooth layer

Bambu Lab A Series Troubleshooting
1

I have streaks in my first smooth layer on my print (dark blue matte PLA)

PXL_20250606_015432598
PXL_20250606_0154325981920×1446 175 KB

PXL_20250606_015429435
PXL_20250606_0154294351920×1446 145 KB

I haven’t changed my settings from previous prints, so I question how best to solve it. Is it only a slowing down?
Couvercle 5x5 3.3mf (2.7 MB)

1 Like
2

Also, I don’t know if it’s linked but I also see streaks where the hotend scraped a surface, see lighter colour lines here.

PXL_20250606_034947229
PXL_20250606_0349472291920×1446 128 KB

1 Like
3

This looks like under extrusion to me. Have you run the calibration process?

4

Yes. And nothing was amiss

5

This definitely seems like under extrusion. Calibration is not always foolproof. Size of the surface area is very much a factor. A Flow Rate that looks good in a small area may not be as good for a significantly larger one.

I would run some tests with surface areas approximating the size you have here and adjusting flow rate between them at 0.01 steps.

I bet you will find one that yields the best result and it will be different from the one you get from calibration.