I get little to none notable z layer lines after I tuned down cooling (by a lot). I’ll share my profile later.
You still see mild (but not excessive) layer lines on where the layer time change drastically:
But I think it’s nowhere as bad as it was now.
That is a good idea. I will try it today when I get
home.
The part in the back also had layer lines but less.
@hotellonely and @MotoGP11991 You are correct, I’m having the same thing where banding lines up with the layer time as well as the geometry. Support so far has been useless, despite my recalibrating the printer in every aspect, what feels like 10 times. One color banding is still apparent as well. Few photos below. FYI, this is ALL bambu matte filament.
Good thing is there’s nothing wrong with your printer, bad thing is this is naturally extremely hard for fdm to solve
I added my marked up photo to my support ticket. Hopefully if enough of us write support tickets they will get a solution if we don’t sooner LOL. Or they might be able to get a real solution permanently on either the firmware or bambuStudio
I wonder if entering all your data to their Bambu studio GitHub would be better than trying it through support. GitHub seems to be a straight shot directly to the dev team instead of having a middle man.
I posted my settings and results here.
Another thought what if part of the problem is it’s slowing down for bridging and the extruder is slightly over-extruding on those layers. I have a large print going right now. I’m wondering if we try unchecking slow down for overhangs on a known part that fails if it changes anything. As in the printhead slowed down but the extruder is still moving at a somewhat fast rate
slow down for overhang usually only apply to walls, walls usually would not cause too drastic layer time difference. unlike bridging, which would introduce huge layer time increase.
FWIW, I used brackets to secure the desk that the H2D is on to the wall and it seems to have solved any Z-axis shifts. It’s now printing as it should. So, anyone with the same issue, I’d start with a solid platform and work from there.
This might sound completely crazy but…
I printed a few items that came out great yesterday. And a bunch over the night and today that came out bad. I’m in a big print and it just dawned on me. All the prints that came out bad have 3 wall loops and the few parts that have similar long straight walls and geometry that would have bad results but came out good had 2 wall loops. I’m wondering if its a glitch in Bambu Studio(or pressure/flow settings) that shows up with 3 wall loops(or more?). This also makes since as all my little kids toys and whales come out great. I print those with 2 wall loops as I don’t care about strength and so does about every print profile on makerworld. The 2 items I printed with 2 wall loops is for the house and I didn’t need 3 wall loops. Every other setting was identical to some of my other parts that didn’t come out good. Might be an anomaly or coincidence.
Can anyone confirm the items that have bad z banding if the item has 2 or 3 wall loops. I’m going to test another file that I can’t get to come out good and try it with 2 wall loops. But I’ll have to wait a bit to try.
The parts I’m seeing on here also look to be parts someone might print that would have additional strength as they look more mechanical than decorative.
I always print with inner/outer/inner and 3 wall loops and my prints on my A1 are amazing. I’ve had the H2D for 2 days and haven’t got a decent print yet. That’s after tightening every loose screw on the toolhead, doing a bed tramming, re-tensioning the belts, and doing the auto calibrations. My filaments aren’t calibrated because I haven’t gotten around to it yet but it was the next thing I was going to try.
But I think you might be on to something…
Right now anything that I need to look flawless (and will fit) I’m printing on my A1 mini. I use 3 wall loops for everything I make (almost all mechanical) and they always look amazing on the A1 mini.
Same exact part, Everything was the same coooling wise. The ONLY setting I changed was I went to 2 wall loops. I’m thinking its a filament profile issue (or bambu studio issue) with their PETG HF and PLA. There’s a little bit of the lines at the start of the new geometry but not the entire layer. These were printed in Bambu PETG HF on the standard .20 mm layer height.
Keep in mind this is ONE test on ONE part.
Just to verify that chamber heat had no effect, which one did you print first? And if you printed them in the opposite order, would the results be the same?
Also, I have been getting really good results with PETG by letting the chamber get warm. Turn the chamber cooling fan down to 10% and let the chamber get up to 40-42°. This helps eliminate any warping.
They were printed a few days apart. But I opened up my original file and just changed it to two walls. My chamber temp I don’t know exactly on these two prints. But I’ve been watching it very closely and I’m always between 33 and 36° C while printing PETG . I could not tell you the exact chamber temperature on both of these prints. I was having really bad warping with PETG to the point where I was using Nano polymer to get them to stick to the bed. It stuck so good it started to give me bubbles on my smooth PEI plate. After the new Beta release my warping went away and I’m printing with no glue at all and no warping.
On a side note if anyone gets bubbles on one of their PEI build plates. Put the plate upside down with the bubbles facing down on the bed, heat it up to 100° C and then shut off the bed and let it cool in the printer. All the bubbles went away.
Yea if I leave the chamber fan at 30% (default) my chamber temp hovers around 33-35 like yours. This was causing the warping for me. Turned it down to 10% and the warping disappeared. Im still on official firmware though.
Try turning the fan down and letting the chamber get warmer on your next print. I’m interested to see if your results improve further.
The whole 2 wall vs. 3 wall thing is very interesting though. I never thought that would have made such a difference. I print everything with 3 walls lol. Maybe I’ll switch to 2 for now.
I’m thinking it has something to do with too much flow/pressure and with 3 walls it has no where to go. And this is why its worse on layers that get a solid layer. Or its just a straight up flaw in Bambu Studio somehow. Cooling might make it better or worse depending on how it flows based off of temp when there is too much filament. I have to do more prints to figure out exactly whats going on. I’m still confused, lol. Unfortunately I’m almost out of the Gray PETG as I’ve wasted almost 1kg messing with this thing and that print is about 2 hours for the one part. The gray seems to show the defect better than white or black.
I have no banding at all with PC FR.
Have you submitted an issue to Bambu studio GitHub about your findings yet? Seems like something they would respond to pretty quickly.
I have not. I’ve never actually even been to their gitHub. I’m printing a 2 wall file right now. Its not great, but its better than all my 3 wall files. I think I’m done printing functional items in PETG until I do some filament calibrations. I really wish BS had all the calibrations that Orca slicer has.
My PETG HS printed with eSun using generic profile and updated volumetric speed looks much better than Bambu PETG HF right now. I did run a calibration print for that for volumetric speed.
