I have a P1p with a Ams 2, I’m printing with bambu matt red pla filiment on a 0.4mm nozzle with a 0.16mm layers height. I’m using the bambu lab default settings.
I have previously printed this model 3 times without issue. on the 4th time it started missing jagged slashes of filiment about half way through the print, which caused layers above to have problems. it looked like it simply wasn’t laying any filament down for several sections.
I cleaned the bed and moved the model to print to one side before printing again. the problem was much worse. what looks like surface damage is because the underlying structure is missing.
I tried again with the gray filiment in case the red was the problem and it was much worse. obvious under extrusion.
ams2 seems to be functioning normally, no weird noises no error messages.
I haven’t tried printing without the ams yet.
I have used this model, profile and filament before without any problems.
The diagonal defects suggest a belt-related issue, so I lightly brush the belt teeth with a toothbrush (of course!), moving the print head for better access to remove dust and debris.
I’m not sure exactly what part of the routine fixes the problem, but it has always worked for me.
The gray part also looks a bit like wet filament or over-extrusion, but fix the diagonal defects first.
you have to watch hot end’s temperature readings while printhead is moving, maybe almost-broken wires, faulty thermistor or heat cartdridge.
you need to watch the readings from the calibration to the errors. when the model is printed scarred you should be looking temps.
I suffered this issue on almost every printer and it is difficult to notice it the first time, included an intermittent degeneration of my prints. not so linear like yours tho
I sat and watched a model go down. It’s almost like it misses several passes out when doing infill of flat sections. So what looked like surface scaring was because there wasn’t any material underneath to adhere to.
Except for the last model in gray that is. It’s like it was trying to print a 0.4mm model on a 0.2mm nozzle. Only about half as much material was going down as was needed.
I can honestly say that I’ve never come across this. How to I get to it, does it only appear under certain conditions or is it just on an out of the way part of the menu?
Personally I would try a new nozzle with renewed thermal paste [this is the p1 right?]. And if that doesnt move the needle go back to the previous nozzle [keep that spare] and replace the heater core + thermister, and again, paste. If thermals aren’t the issue, nozzle clog isnt the issue; then extruder or something like PTFE snag is the issue, its basically gotta be one of these to have a problem of “no filament comin outta the hole”
Aside from crazy warranty things. I hope youve got a ticket open w/ BBL to hear their ideas.
I cleaned the nozzle, the extruder gears and ran a full calibration and flow calibration using dry Bambu Matte PLA with Bambu Lab’s default settings.
This is what it looks like about half way through. There are these entire rows where bits are missing. It looks like when the print head changes direction the filament either doesn’t flow or doesn’t stick.
I’m suggesting this because you said you narrowed it down to your AMS or filament buffer.
I recently had a problem with my AMS Bearing support for internal hub unit (for the AMS).
My printer and AMS was only about 1 month old when the filament started not feeding properly I managed to troubleshoot the problem down to that part after being able to print just fine from an external spool. I was sent a replacement part but managed to print a replacement part so was up and going in no time.
I wasn’t able to find out exactly what caused this, but it was something to do with my AMS2Pro.
I stripped it down, cleaned it, replaced the PFTE tubes and did some more calibrations and flow calibrations, and it’s now running “almost” like it was before. Something is still a little off as the seams are rougher and ironing isn’t as smooth, but I’m 99% of the way there.
