Greetings everyone. I’m hoping I can get some help troubleshooting Bambu PC filament on an X1C. I keep getting failed prints. Using stock settings with the Engineering Plate and Bambu Gluestick. I’ve dried out the filament multiple times with no improvement. 1st layer looks very sloppy even after drying out the filament as Bambu recommends. However, when the prints do make it past the first couple of layers they start to spaghetti at layer 25-35 with 0.2 mm layer height. I’ve only had two prints complete by slowing down the volumetric to 10 cubed, both being narrow and tall (fan ducts). I’ve cleaned and lubed the lead screws a couple weeks ago, got the printer a couple of weeks ago.
This is my first time printing filament other than PLA, which prints beautifully like it should if you’re wondering. Any tips/advice would be appreciated. Thank you.
I’m thinking the filament still isn’t dry enough. The picture with a long string hanging from the printhead is what I associated with wet filament. The extruder stops moving, but the moisture in the filament continues to heat and expand driving more filament out of the extruder. A little “snot” that hangs off is that worst of what you’d see if the filament was dry.
I agree with @RocketSled; from the pictures, the wet filament is the most likely cause.
It takes a long time to achieve RH < 20%.
Nevertheless, PC is a tricky filament. Many things can affect it.
I would advise carrying tests with a smaller print file to reduce filament waste.
The door opening may cause the calibration lines to lift. Heat the chamber before starting the print and keep it closed.
I’ll give the spools another round in the oven tonight, but I guess I need to move my printer. It’s currently in the garage for the VOC’s, but I’ll build a Bento Box and move it inside somewhere. I’ve been monitoring the AMS temp and humidity sensor levels and they’ve been good, but if moisture is going to keep being an issue then the garage won’t work. I’m going to give PC filament a break for now, I just wanted to do strength testing but I don’t have a real need for it. Will ABS be easier to print? I want to start printing Mercury1 and Hydra parts.
While it could be a number of factors causing this, I agree with the others. Make sure the moisture is out of it. Looks to me like its clogging. Not a full clog, but just partial clogging. Are you using the base Bambu Lab profile with no changes?
I recently moved my printers to the basement, which has higher moisture.
Nevertheless didn’t have any issue with that. However, I upcycled an old closet to enclose both printers and took extra care regarding filament storage.
In my experience, ABS is significantly easier to print. I don’t use it more often because I prefer ASA for regular prints. The only advice is generic: a clean sheet, no air drafts (i.e. do not open the door), and beware that the maintenance is more demanding.
PC prints are a must, but I spare them for demanding parts. In my experience, you need a tune-up. It is one of the materials I don’t rely entirely on the default profile. Some advice based on my errant experience:
The first layer needs to be perfect stick to the bed to hold the entire print; I only tried PEI sheets combined with lower speed. From other users’ experiences, it seems that other sheet materials require the use of a suitable glue able to resist high temperatures;
Heat the printer case by starting the bed heating previously and avoid any draft;
Top layers require a high infill. Otherwise, they will drop into the void spaces - I also print top surfaces at a lower speed;
Do some tests before printing - I usually look at the critical parts of my print and design some shapes with similar shapes at a lower scale to see how it goes - this will help to avoid surprises;
Luckily, my PC prints never had large bridges - if yours do, do intensive tuning on the bridge flow and cooling. Otherwise, I would guess that it will drop due to high temperature, and I doubt that it will be possible to recover with a more significant number of layers.
I will do my best to eliminate moisture from the list. With all the stringing and blobs I’ve had at the nozzle I could definitely have a clog, I’ll swap out the nozzle with the spare to eliminate that as well.
I forgot to answer, yes I am using the default Bambu settings for Bambu PC filament. I tried doing manual calibration but I couldn’t get past the first layer. Slowing down the print speed help, I started getting consistent 1st layers, but I started getting failed prints after 20-30 layers.
Before you swap out the nozzle, just run a different filament through it. Do like a calibration cube in PLA or something, PETG likely ideal. If that comes out good no need to change the nozzle. But there can still be some factors causing clogging. Temps and speeds being high on the list. I also notice some filaments will require that I open the printer up when printer to avoid heat creeping into the warm end of the hot end. You can’t quite do that with PC, but you may be able to find a workaround to reduce the heat there. Maybe try the lower end of the temp range. Maybe your printer prints hotter than normal… who knows. Maybe even try a temp tower, its a tall difficult to print in PC test that may give you some ideas.
I’m with the person that suggested doing some quick tests, that way you don’t burn through the PC trying to get it to work. Small tests prints that are 10x20mm blocks and maybe 35mm tall, or something in the 20-30 mins range. Do a test of an idea and then assess it. That should be a good torture test for PC.
I had a similar issue with my prints stringing and under extruding after 20 to 30 layers. All that had changed was I moved my AMS units to find that the PTFE tubing was bent a little to much, allowing the filament to bind in the PTFE tube. I re-orientated the tubing and the problem appears to be resolved. See next print I am busy with after the intervention.
I had a busy weekend but Sunday night my spools did another round in the oven overnight and yesterday I moved my printer out of the garage and into the guest restroom so I can utilize the counter space and ceiling vent. My wife was not happy at all, lol. I did a calibration and a test print with a spool of black PC that’s also been giving me trouble. I was able to print out all the pieces for the BentoBox V2 and everything fit nicely. I then printed a complete EVA 3.0 without failure. I have the BOM items arriving today along with my first roll of ABS (esun). Once the BentoBox is complete I’ll try the white PC and ABS. Hopefully the white PC is good to go like the black roll was.
Have you checked the humidity and temperature in the space where your printer is? I had such a problem. Installed a dehumidifier and that solved the problem. All my prints now turn out great. Or I should say my 4 year olds prints. I bought the system for him and he loves working with it. Although dad is getting tired of printing dinosaurs. But he would be a good testimony for how easy the printer is to use.
I have another problem with the Bambu PC, both black and white. Despite being dehumidified multiple times, there are these empty areas in the prints (not at the seam) that seem to be under-extrusion. I used the preset Bambu profile
I would check your extruder gears see if they are filled or worn.
I would also check your nozzle to see if the thermopaste has dried out. This would cause temperature fluctuations which could cause poor extrusion. This is a very good thread explaining that.
