Just updated to the newest firmware and newest version of BambuStudio. First problem I’ve had with this printer…
Just tried same print on a different P1S with the same roll of filament (Bambu matte black) and had the same issue.
Will try a different roll on each printer next and then try to figure out if it is the file, I guess.
What would be causing the wall line to do this in t
Looks like it is 100% the filament. Perhaps I need to dry it? So far I’ve used 20+ rolls of Bambu PLA without drying and have had no issue.
Same roll of filament causes the same issue on two different printers with different prints/files.
Swapped the filament and printed the same files on the two printers and it didn’t do it.
It looks like there is a problem with newest firmware. I was trying to run calibration after firmware update, but it can not even start, can not even load filament. At the same time it prints with this same filament. Really weird.
I can’t get great photos, but I think the filament is just bad. It feels very bumpy and wavy if I run it through my fingers, not like every other roll so far.
Matte has an increased moisture uptake due to the increased pigmentation. So drying is always a good idea. Especially new filament.
Some bumpiness can be normal. Usually though on loaded filaments (Wood, CF, etc.). You could however take a pair of calipers to check the mean diameter and ovality. Those kind of defects are rare, but they do happen.
Considering the failure pic’s, is your chamber temp above 35°C? In that case, heat creep may be occuring.
Another potential cause for this type of failure can be a partial nozzle clog. In particular if it is travelling down from the extruder or even the PTFE’s.
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I’m still trying to troubleshoot the problem, but so far it seems to be occurring on all four P1S’s I have. I spoke too soon about the filament being the problem as another roll started doing it too, just not as bad as the pictures.
So far the only thing all four printers have in common is I just updated them all this morning to the newest firmware. Going to revert/calibrate them all and continue testing.
Did you resolve the issue? I have the same problem at the moment. Would be nice to know what you have done 
