I’m running into a print quality issue with my brand-new H2D and wanted to see if anyone else has experienced this.
The problem: small and larger gaps/holes appear in the top surface, specifically at the corners. Most of the surface fills in cleanly and the transitions elsewhere in the same print are perfect, but at the corners it becomes inconsistent with noticeable gaps.
What I’ve already tried/checked:
Filament was properly dried beforehand
Calibrated flow using a Pressure Advance ¶ test
Issue occurs on both the left and right nozzle, so it doesn’t seem to be tied to one toolhead
Overall flow looks good to me elsewhere on the print, so it doesn’t seem like a general under-extrusion problem
What’s strange: I printed the exact same files on my P1S and did not see this issue at all - the corners came out clean. The H2D has shown this problem since literally the first print out of the box, so it seems specific to this machine or its firmware/slicer profile rather than a filament or design issue.
Has anyone else run into gaps forming specifically at top surface corners on the H2D? Any settings you found that fixed it (e.g. wall/top surface overlap, corner speed, seam settings)? I’ve also opened a ticket with technical support and attached photos, but figured the community might have already solved this one.
As I find Bambu’s wording potentially confusing: I hope you’re aware that the pressure advance test calibrates flow dynamics, not flow rate. A different test is needed to calibrate flow rate. Both are important for good surface quality.
With that in mind, you should probably re-run your filament calibrations for flow rate and pressure advance (= flow dynamics) again.
I’d be happy to hear whether you could resolve your issue.
If it persists, you may want to have a look at the topic “First/Top Layer Gaps on H2 Series — Confirmed Bug, Still Unresolved” in this forum, or check out the Reddit thread “H2C / H2D / H2S First and Top Layer Gaps — Known Bug, Still Unresolved” (sorry, I’m not allowed to post links yet; please use the websites’ search functions).
There seems to be a bug affecting the H2 series when it comes to gaps in infill, but it’s still unclear to me whether it’s an overcomeable user/calibration error. That’s still enough to currently hold me off from buying one of those machines, as the H2D (or C) would otherwise be exactly the machine meeting my demands.
