The 3 botton layers printed perfect, but from the infill onward there is some kind of tear-away effect. I stopped and restarted the print several times alway with the same effect.
I’m using Bambu PETG-CF on an X1C with obxidian nozzle and default printer settings at 100% speed. Printing at 50% speed improved the problem but I didn’t have patience to wait that long.
Is this under-extrusion ?
I had no problem printing the same model in PLA.
The same GETG-CF spool printed other models without problems before.
Check the thermal grease on the nozzle as it can degrade/dry out over time and you won’t get as good of heat transfer when the nozzle is printing fast.
Don’t think its under-extrusion, the base layers look decent enough.
I think its wet filament, but that is just a first guess since you didn’t mention drying or that it was sealed up away from humidity since you last used it successfully.
Did this spool print without problems using that same nozzle? Seems like another variable that could lead to issues.
Finally, for PETG-CF I would use gyroid infill or some other non crossing pattern, rectilinear is asking for problems though it likely isn’t the cause of this specific issue.
I found the culprit.
After installing the Obxidian nozzle, I had increased the Volumetric Flow Rate to 32 mm³/s for PETG as instructed on the e3d website. Allthough that worked fine for other prints, this one had a higher infill ratio which seems to be not compatible with high volumetric flow rates.
After lowering the flow rate te 24 mm³/s, the prints are fine again.
