H2C / H2D / H2S First and Top Layer Gaps — Known Bug, Still Unresolved
I wanted to create a summary posts regarding the first layer issues on the H2 series printers.
It would seem there are others dealing with first/final layer quality issues such as gaps, pinholes, space between lines on first and/or top layers and have been sent through rounds of bed leveling, flow calibration, hotend swaps, and hardware checks by support without resolution.
A Bambu developer on GitHub confirmed this is a known issue and has stated a fix is being worked on (as of February 2026). Despite this, many are still being sent through the same circles with tier 1 support including hardware troubleshooting steps with low chances of resolution.
There are mixed reports of replacement hardware solving the issue vs others with no change after full machine or toolhead assembly swaps. Interestingly, if I print the internal storage test Bambu Panda, I don't have any issues you can see in my pictures for other prints.
This is happening across H2C, H2D, and H2S owners and has been more widely reported over the last 6 months with the arrival of the H2C, which is appearing to likely be more prone to this issue.
The official bug report for Bambu Studio is here:
https://github.com/bambulab/BambuStudio/issues/9768
If you have this issue, please consider adding your report to the official GitHub. Include what you have tried, what has possibly helped or has definitely not helped.
The more documented reports from different users, the more likely this will be resolved on a what is advertised as the flagship Bambu series.
Below are reference threads showing how widespread this is (I'm sure there are more, just what I have been collecting while searching for solutions):
GitHub
https://github.com/bambulab/BambuStudio/issues/9768 (main issue)
https://github.com/bambulab/BambuStudio/issues/8784
Bambu Lab Forums:
https://forum.bambulab.com/t/h2c-under-extrusion/241961
https://forum.bambulab.com/t/gaps-in-colour-when-using-multi-colour-on-first-layers-h2c/229542
https://forum.bambulab.com/t/another-first-layer-problems-thread-h2c/251914
https://forum.bambulab.com/t/first-layer-is-not-squished-enough-visible-gaps-h2s/248800/9
Reddit:
https://www.reddit.com/r/BambuLab/comments/1qa97zt/new_h2d_first_layer_and_top_layer_not_great/
https://www.reddit.com/r/BambuLab/comments/1uab85h/hc2_after_just_1_week_has_me_underwhelmed/