Edit: Setting the max speed for walls to 50 mm/s solved it! I feel like this should be limited when you select the filament, but oh well.

Hey, so I have recently gotten a Bambu A1 and got a roll of PLA and PETG. The PLA is printing very nicely out of the box but the PETG not so much. Since I’m still very much at the beginning of my 3D printing journey, I don’t really have a good way of drying my PETG yet, I just stuffed it in a plastic ziplock bag with all the desiccant bags I got from the rolls and printer and stored it that way. I’m already planning to print myself a filament enclosure, I just haven’t gotten around to buying the bearings, etc for it.

I’ve done some functional prints with no angled (overhanging) walls and they have turned out pretty good. When printing on supports the overhangs are ugly af, but no weird pattern like this.

The issue I’m tracking down seems to occur on ~60+° overhangs, that really shouldn’t be an issue. I’ve done a sliced test print and took some photos, any idea what causes this?
Thanks :)

Bambu A1, standard 0.4mm nozzle
Bambu PETG Basic filament and profile using Bambu Studio
Some settings I played around with was flow rate (0.94->0.95) and layer height (0.2mm -> 0.15mm) but it seems to make no difference.

(note, on some of them the part is photographed upside down.)

  • bigredgiraffe@lemmy.world
    link
    fedilink
    English
    arrow-up
    2
    ·
    edit-2
    5 months ago

    I agree with the other poster, this is wild. It seems like It is limited to one axis so maybe it’s a slicer or printer bug. Does it do it if you print it out of PLA? PETG is cranky all around but I have never had it do something like that hah. Is this part online somewhere? I can try to slice it and see what happens on my x1, I’m curious now haha.

    ETA: you should also open a support ticket, they have great suggestions sometimes.

    • Jawa@lemmy.worldOP
      link
      fedilink
      English
      arrow-up
      1
      ·
      edit-2
      5 months ago

      Thanks for the input!
      So the thing I was trying to print was this: https://www.thingiverse.com/thing:6365845
      Ideally you’d just print it in PLA but I only had one colour PLA so I thought, might as well gather some PETG printing experience :D
      The part in question is red_panda_low_poly_V1_-_head_A_red.STL and I tried to print it on an odd angle to make sure that most of the outwards facing walls were on the top, because anything that needed support turned out so hideous.

      Also it seems to appear on any side of the model, where you have a slight overhanging angle, in no particular axis :)

      I’ll print it in pla once my current print is done :D

      • IMALlama@lemmy.world
        link
        fedilink
        English
        arrow-up
        1
        ·
        5 months ago

        PETG can do supports, but it’s not pretty if you have steep overhangs. It’s also kind of annoying to sand, but you can do it. That said, if you have a heat gun or hot air station you can get a lot of the surface shine back after sanding by warming the surface of the print up a little. You do have to be careful to not overdo it though, otherwise the model will deform.