Print Quality Issues Near Limits

Bambu Lab H2 Series
1

I’ve had an X1C for a couple of years and it’s ‘just worked’! It’s been fantastic. I purchased an H2D a few months ago and haven’t had much chance to get to use it as I’ve been busy with life.

The past week I’ve finally had a project that I needed to use the H2D for. Most of the models I’ve made are relatively basic with geometry that I don’t believe is challenging, but I’ve had multiple failed prints.

I’ve been working with PLA, HT-PLA, HT-PLA-GF and PETG. None of the prints have been multi-material, but I’ve mostly had a problem with the HT-PLA and PETG. The same issue has come up, one leading to multiple failed prints, and another, similar model that managed to complete but was on the verge of failing.

I’m also only working with one of the heads. After a couple failures and errors with overloading of the filament feeder I assumed I had a clogged nozzle. I swapped the nozzle and still saw the same issues crop up on the next print.

Edit: I’m struggling to get the images uploadedGoogle Photos Link

2

Have you checked if the corners warped up?
Seems like an adhesion problem.

3

I thought the same, but there was not an adhesion issue.

4

The fact, it only appears in the corners strongly indicates that the corners warp upwards when the top layers are printed. You might want to reduce the cooling a bit.

Measure the general height and compare it with the height of the corners. The corners might be a bit lower due to warp. You can consider a brim with 0 distance. That should keep the corners down.

5

I’ll do those checks shortly, I’ll also check the parts with a surface plate to see if maybe the plate was warping along with the print.

6

So, I checked one of the failed prints that I had on hand, and there’s roughly a .8mm thickness difference from the center of the square compared to the corner. I’ll give it a shot with a brim and see if that solves it. I don’t have a lot of room left over on the build plate for the brim though.

Thanks for the help!

7

Can try mouse ears in the corner or pads with sprues / a runner channel that would make things easier to clean up than a brim.

8

Additionally you might try to raise the b d temperature 5 degrees.
When you are that close to the edge of the plate, that might help too.
Additionally you can consider washing the new plate.

9

I’ll give those a try too. The plate was washed with Dawn immediately before the prints.

10

The corner of the plate are the most likely area to touch when handling it.

Success!