It is nice not having to do the long purge between petg and pla, like on the other printers.
This looks like a layer time issue. What do the sliced previews look like?
looks like a huge z banding problem too. Suffering from that also, there is also a thread on here for that too.
I already opened a ticket with them and send them pics and the project files. Hope they get to fix that soon.
You can play with the minimum layer time setting under the cooling tab of the filament profile. You can also play with the max volumetric speed and wall speed settings. Make one change at a time and reslice to see if you’re moving in the right direction.
Just keep in mind that the lower you go on the wall speed, the more likely you are to introduce VFA. Bambu’s default wall speeds are set pretty good in order to reduce VFA. You won’t see these in any previews though, only on the print.
Infill type has a large effect on layer times as well. If you don’t exactly need strength, try aligned rectilinear.
Be sure to check the flow and speed previews as well as those can also have an affect on outer wall quality.
So what is interesting is I did a print test w/the X1C and got no banding in these regions… slicer for x1c and h2d shows the same in the layer time view…
There’s a whole host of settings that can affect it other than layer times. Flow, speed, cooling, filament tuning, etc. if all else fails it very well might be a machine issue, but don’t want to jump the gun before ensuring that slicer settings isn’t changing anything.
In the sliced preview. Try going down to the layer of one of the bulges. Then use the slider at the bottom to see what the flow and speed are for that layer. Then go to one of the layers right next to it that are seemingly printing in its normal spot and compare that speed and flow with the bulged layer.
My trick is always running outer wall at 50mm/s unless quality doesnt matter. Ive always done this.
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So that is odd, before the banding, it prints at the inner wall layer at 293, and outer at 164.
Where there is banding, it’s printing inner wall at 293 and outer at 187.
Why would the slicer increase speed at random points but only for the outer wall?
It could be that because of a color change, that increases the layer time, which then removes any kind of speed limit and allows it to print slightly faster. Idk, that probably makes more sense in my head lol. The max volumetric speed plays a role too.
Try setting your outer wall speed to 164 and see if those bands turn the same color. You can also just try setting your wall speed even slower to ensure it’s even. If I don’t care about VFA, I have my outer wall speed set to 80 and that usually makes the entire models outer wall, other than overhangs, nice and even.
Do a quick test print. Set outer wall speed to 80, min layer time to 8 if pla or 12 if PETG, and change infill to aligned rectilinear.
So odd, if i force 80 on the outer wall speed, the lines don’t go away. When you look at it dead on, it definitely has something to do with the color change. Where there is no change look at the orange bands, two colors is yellow, three is green. It’s total layer time, having nothing to do with the individual nozzles. Would be good if you could split it like that… Running a test now at 50 outer wall speed and aligned rectilinear
I have a hunch the slicer is adjusting the outer walls to compensate for longer layer times. Leading to inconsistent outer banding.
Yea, you probably won’t be able to get it all the same color unless you change your min layer time something crazy high. In that instance, just make sure the flow and speed previews are even.
Speaking of which, what do those previews look like?
Just keeps getting worse… doing another nozzle calibration now… certainly seems to be centered around color changes. I’m suspect it is not realigning the next pass after a nozzle change.
L and R photos shows you how the layers shifted left nearly 1mm
This seems to be a layer shift.
Definitely no z-banding.
You might wanna check if your hot-ends are mounted securely.
Did you follow the belt tensioning procedure?
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Yea, that one is definitely a layer shift. Have you done the high precision nozzle offset calibration?
yes, i’m redoing nozzle offset again, along with tensioning. This AM I took apart all the hot end screws and ensure they are tightened down… Stand by…
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Were your hot end screws all varied in torque/tightness? Mine were all of the place.
yep they were all tight, i re-torqued them all… latest test, more failures… so frustrating… i may print this on my x1c overnight, will take forever but will prove its a nozzle align issue… at least that is what I’m thinking at this point?
