I have an X1C w/ AMS. A while back, I purchased 2 spools of BL matte PLA, white and ash gray. I started with the gray while printing an AMS riser. This works out to nearly 2kg of filament, so after finishing the first half, I ordered another spool of gray, along with about 4 other matte colors.
Aside from that first print, EVERY single print I’ve attempted with any matte color has been utter trash, including the next roll of ash gray. Bad layer adhesion and underextrusion seem to be the 2 most common issues.
I’ve tried drying them, calibrating flow rate and dynamics, printing with the door open and lid propped up, printing at 50% speed. I think I tried different temperature tests too, but it’s been long enough I can’t say for certain. Nothing I’ve done has seemed to have any effect.
What am I missing? I know now that a lot of people have had issues with matte, but just as many seem to be able to print it off with no issue. This is BL filament, using BL presets on BL hardware. So why can’t I get this to work?
PETG, standard PLA, none of those have given me any issues, it’s ONLY the matte stuff.
If it was just one spool, I’d toss it and say I learned a lesson about researching filament before buying. But I have over $100 of unused matte filament, and I’m hoping it’s just some setting that I haven’t thought to try.
Can you post some pics? I’ve had some under extrusion issues with matte PLA but nothing flow calibration didn’t fix. I have about 5 spools and they’ve all printed fine.
It’s a hard call for me - some looks like moisture but not exactly what I’ve seen.
What are your filament drying steps?
Unfortunately filament fresh out of the shipping box and bag can still be too wet to print well. These printers print fairly fast which makes water removal more critical to getting good prints.
I have a food dehydrator that I modified to hold filament, and am able to dry for as long as I want. 4 hours, 12, 24, I’ve done all of these at 55C, with no noticeable change.
Any desiccant in the AMS really only keeps filament dry but doesn’t dry it to any practical extent because it’s not heated. It’s important to filament care though, and those numbers should be good if your filament is dry going in. If the AMS numbers stay low, that would indicate the filament is fairly dry.
Maybe it’s not moisture? Someone else may have suggestions.
Well, with the spools having been dried for say 12h at 55°C, I’d guess that moisture is not or at least no longer the issue.
Did you give your printer the regular maintenance do over? Rod cleaning, spindle lubrication, belt tensioning, lidar lens cleaning?
It’ll not resolve the issue, but your printer will appreciate it.
Next, you probably want to do a number of hot hex wrench (!!!) cold pulls (Nozzle/Hotend Unclogging Procedure for X1/P1 | Bambu Lab Wiki). In my experience, that is the only way to reliably remove a contaminant from the nozzle. The simple clog procedure just pushes the contaminant further up.
I almost excusively print in matte pla with generic settings and have never had this issue… The only similar time Ive had similar results was a hair under the build plate (which I guess was enough to throw the z off in certain spots).
Are you in an unusually humid climate? And how long ago was awhile back, and were they sealed the whole time? My poorest results are always from old filament, but ‘old’ seems to depend on a ton of factors
This looks like simple heat creep. This assumes you don’t print with the top off or door open when printing PLA. Although this isn’t always needed, however, if the printer is in a warm place and is closed up, there is a chance that the hot end will start to soften or melt the filament too soon in the filament path. And we all know pushing a wet noodle through a small hole will be difficult.
If this isn’t the issue, its also possible there is a partial clog. You can check this by changing to the spare nozzle.
My next guess would be, to return to the stock profiles if you have modified them. These do look like they could be printed too fast as well. Easy way to check for this is to start a print and when you see it start to print badly, change it to “Silent” speed. This will half the print time and if the profile is too aggressive, you will see an instant improvement when it slows down.
Well…this is embarrassing to admit, but given how much effort everyone put into the responses, I feel it’s only fair to give you an update.
I have an AMS that sits on top of my x1c. I have very little space on the sides of my machine, so I never made any effort to try moving it off the top. I do have a little latch thing that props the lid open, which I (mistakenly) assumed would give similar venting properties to having it removed entirely, especially with the door left open.
I was wrong. I took the time to clear space and take the AMS off the top of my machine, fully removed the glass top rather than propping it up, opened the door, and ran another test print.
Go figure, it came out nearly perfect
I’m now doing a more complex (but still fairly small) print to see if my luck holds, but this is the best I’ve had so far.
Honestly… I have never needed to open mine up for PLA, but I know that it is a possibility. Now that you know what the signs are, this problem will effectively become a non-issue. However for me, I do see this problem on occasion with TPU, so be aware there too.
After I did my follow-up print last night—which was pretty small—I decided to try a larger print, one that almost runs the perimeter of the print plate. I forgot to take a picture of the small print on the plate, but basically it’s Kirby’s feet here:
Here’s a question for the group: why does it seem like the first layer is almost ideal on the side closest to the auxiliary fan?
Since I’ve run out of immediately obvious solutions, I’m going to start working through the various maintenance/troubleshooting ideas that have been thrown out. I also have an active ticket with BL, and they’ve tossed some suggestions at me as well. I’ll update if there are any changes.
Once again I am here to bare my stunning incompetency to the internet.
All of the guesses that were related to heat creep, you’re probably right. But not for the reasons you thought.
After my last post, I took apart the printhead, disassembled the extruder, verified there were no clogs, cleaned all the gears and nooks and crannies, and then reassembled everything.
Then, to be doubly sure that somehow my white matte PLA hadn’t been completely waterlogged, I took it out of the AMS and it is currently sitting in my dryer. Afterwards, I scraped the filament off the plate. I recently threw away the box that was sitting under my desk where I would toss scrap filament. So instead I decided to throw it the scraped-off filament in the poop chute box behind the unit. It was then that I realized that the box I’ve been using to catch the poop is a little wider than the machine, and covering both of the vents Yes, I have trimmed away the offending sections and the vents are now able to draw or blow air unimpeded.
Anyway, here’s the same filament I used yesterday after the first layer of the same print I attempted earlier today. It looks promising.
As of the time I’m posting this, it’s a few layers in and looking almost flawless.
I appreciate everyone’s attempt to help me, and I apologize that my stupidity is so deep it wouldn’t have occurred to anyone to verify something so obvious.
While the issue I was having with this particular roll of red matte PLA has been resolved (for the most part), I still was getting awful print quality with the white.
Since my last post, I’ve cleaned the carbon rods, disassembled and cleaned the extruder gears (there was no debris), and cleaned/lubed the Z screws. I also verified the nozzle has no blockage and had a perfectly straight flow when advancing the extruder.
Afterward, I attempted another flow rate calibration print with the white PLA that’s been giving me the most trouble (literally every print has been awful). And—drumroll please—…it still sucks!
To confirm I wasn’t just losing my sanity, I repeated the exact same print with the red matte and it came out almost perfectly. So now I KNOW it’s not a printer issue. I think I just got some bunk filament.
So BL has offered to send me 2 rolls to replace the matte that’s been having problems (white and ash grey). I requested basic PLA, I’m done with this matte drama.
and 
Yes, I have trimmed away the offending sections and the vents are now able to draw or blow air unimpeded.
