Interesting
If you inspect it in the slicer preview, is the “support transition” the topmost interface layer, or the bottommost one? What is its layer height? Does it run at a different speed/fan?
its the darkest of the greens, the “bottom” of the interface sandwich
Layer height appears to be .16 with independent support layer height off
and 0.30something with ISLH turned on
Additionally the support interface seems to ALWAYS be vertical to the support structure lines, in these screenshots i set pattern angle to 45 degrees, expecting only the base pattern to rotate, but all of them did.
The interface does rotate with the pattern in Orca
But it stays under angle to the structure
I suspect thats what cause the support structure to collapse under its own weight?
I’m not sure what a good solution is. It would be nice if we could change the speed selectively on different parts of the print to accommodate these kinds of failures. For instance, imagine you could “paint” a speed onto different parts of the pre-view print.
I don’t know if this is what you had in mind and my memory is a bit hazy here but you can change the speed temporarily on layers. Something like, you add a cube to the part and make it a certain height. Then you add a speed modifier to it I think. Someone feel free to correct me. You may also be able to do it using the layer hight feature where you input a layer hight and it shows it in green then choose an effect.
Sadly im out of time for testing for now. I spent nearly 30 continuous hours on troubleshooting this, and now my production is way behind, so i need to marathon a bit ahead. Will certainly try again soon , but for now i resorted to tree supports. Its close to the bridging layer so ill post results with that too, soon, but itll be a bunch of hours before i have the h2d free for testing again .
And honestly… Thats not why I paid 2.5k…
Yes, tree supports work as expected. Issue lies only with normal, and im becoming sure its something to do with that additional layer
I notice that I sometimes get 2 interface layers while asking for 3.
However, so far no issues with supports.
But then again, I don’t use the same material for the support interface. I simply use a PETG interface for PLA parts, and PLA for PETG parts.
I only need a shadow (support) profile and match the bed temperature to the material it supports.
This is one of the reasons that I wanted a dual nozzle machine.
I also have the feeling that material profiles that have been modified earlier for a different Bambu machine interfere with the H2D material profiles.
Something that I can’t prove because the H2D is my first Bambu Labs printer.
It might bug out if you enable independent support layer height iirc.
However, we have to admit that the current status of support generation is a hot mess. It has went completely garbage since 2.1.0 as default tree supports would now grow into the model. The normal support would also be generated very unreliably causing the kind of failure that OP is having, unless you tune the support settings carefully to avoid long straight single layer lines. It’s not only just bugging H2D, but also other bambu machines.
E.g., for this print this support would highly likely to fail because it’s basically printing 1 single layer of support line that is weak, and potentially get not enough cooling or too much cooling at the same time!
My current solution for this particular issue is to either adjust pattern angle for a specific part, or change the base pattern type to either Rectilinear Grid or Honeycomb. Honeycomb is a bit too slow and using too much filament, so most of the time I just use rectilinear grid instead.
This is what rectilinear grid looks like. Much less likely to cause that issue.