Moisture is not the presumed cause of your 0.6 mm issue, but it can confound tests. Bambu’s filament guides let you confirm drying temperatures, handling and AMS compatibility before spending time on unnecessary changes.
Why it matters: This is a concrete choice or experiment for today or this week.
Practical next move: Keep the known-good PLA spool constant across your nozzle comparison.
Go to Source — https://wiki.bambulab.com/en/filament-acc/filament
Official filament guidance distinguishes moisture symptoms from nozzle faults. Action: Keep the known-good PLA spool constant across your nozzle comparison.