New P1S poor print quality (banding issue)

[A_Niemi_Designs]

Hello, I have recently received a P1S printer and I have been having some issues with a banding pattern appearing on my prints. Seen in the following photos:

I am using the generic PETG preset with Elegoo PETG and have done a flow dynamics calibration on the filament. I have tried the procedure to “balance” the belts (trying to get them to run in the middle of the rear idler and not on the flanges and recalibrating the printer afterwards twice with no difference in results. The procedure I followed can be seen in this video: https://www.youtube.com/watch?v=izdBZ9IQfqI

I am at a bit of a loss when it comes to what the problem might be at this point as the belts seem to have a very limited portion of their travel touching the flanges (I have not been able to get the belts to ride completely centered in the idler). It is worth noting that the Bambu brand PLA that came with the machine seems to have the same issue, just less visible, with the glossy PETG highlighting the problem.

[user_958860865]

PETG seems inherently harder to get perfect prints. At least that’s my experience.

Slowing down the outer wall speed has helped when I’m aiming for (near) perfect prints.

Switching to outer wall first makes a big difference as well except for overhangs.

Reducing layer height also helps reduce and even totally eliminate the banding.

These printers are lightning fast but slowing things down often gets better quality.
If you want perfect quality you might have to sacrifice some speed.