Help! So I’ve tried to fix this changing many parameters. I’ve tried changing the line thickness, the number of walls, etc… how do I fix the attached picture where the very top layer isn’t “thick enough” and it’s showing a gap underneath where the wall and infill don’t overlap?
Is your flow rate calibrated?
I would suggest increasing the number of top layers. The first layer above the infill is always more of a bridging layer. It then takes a couple of layers to become nice.
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Yes, good suggestion though!
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You do not have enough top layers. What is the slicer set to for the number of top layers? It should be no less than 3. But you may need more for less-dense infill settings. Bottom layer, too, TBT. If for no other reason than strength/durability.
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So I did change top layer parameters. Top shell layers is 6 and top shell thickness is 2mm. But top layer minus 1 slicer models it going around in circles. The very top layer parameter “only one wall on top surfaces” is set to top surfaces, and it does make that final one wall surface. It’s like that’s the one not filing in properly??
Do you have a 3mf to share so we can look at your settings?
A screenshot of the sliced model (preview tab) is always a must in these situations.
YES, thank you! So i tried to print again. I took a pic mid-print at layer 46. In the studio preview it shows “filled in” properly. But in real life you can see its like it didn’t print the last line of fill next to the wall?
Attaching .3MF, print preview snapshot at layer 46, and real life at layer 46.
Thank you!!
D102 Metals Send.3mf (201.4 KB)
All your top surfaces look “ratty”. The “D” is just the worst.
Not exactly sure what the problem is. 6 layers should be more than enough.
It looks to me like you may be under-extruding. Either flow calibration is off or the nozzle might be partially clogged, or the extruder stepper isn’t stepping correctly.
But if you changed a lot of parameters, including ones like the extrusion width value, I think that needs to be addressed first. You shouldn’t have had to make any changes, defaults for everything should have printed just fine. Reset all the settings back to their defaults. See how that looks compared to your last print. Post the results.
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As mentioned before here. Is the flow rate correctly calibrated?
I mean, it calibrates the flow rate by default before every print right?? I shouldn’t have to do anything special. If I do please let me know! This is printed on my H2D I just got… I have an X1C and it’s always been perfect
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Yeah I have almost always printed with defiant values and it’s been prefect. This print is such an oddity in my years of printing. This is in my brand new H2D. I’ve had an X1C for years with no problems.
What’s really really weird is I printed just “the D” by itself and it came out absolutely perfect with same settings!
I have underextrusion on top surfaces only. I already had a ticket with bambu and they refuse to acknowledge the problem.
Bottom layers, walls and infill look perfect, its only the top layer that looks underextrudet.
They send me a pre sliced cube to test the machine and you can easily see the under extrusion on the top surface:
When i pointed that out there response was:
“I also don’t see any under extrusion. From this print, the machine is operating as it should.”
Yep, that seems like it’s very similar to what I’m experiencing. Can you reopen your ticket and attach this thread as another example maybe they’ll think about it some more? But yes, I can see in your picture a little under extrusion. I don’t think it’s as bad as mine but still, you can’t see it.
The best way would be for you to also open a ticket in case they have questions about your printer, profile or filament.
I wonder if small area flow compensation has anything to do with this.
All settings reset. Forced flow calibration to be “on” instead of “auto”… same result on top layer and same result around layer 46 in the middle where there is a gap!
Yeah, I think I’m at that point 
Ohhh, tell me more! Is that a parameter?
Is this PLA and what is the flow ratio @ ?
Which wall generator are you using?
What is your infill-to-wall overlap setting?
Are you adjusting the top surface flow ratio? Keep in mind that you need to have developer mode enabled to do that.