Support Issue - Generating support under negative space?

[DCAP11]

Hi there!

I’m having some trouble understanding Bambu Studio and how it generates support structures. Previously I have used Markforged’s Eiger slicer. I have attached some pictures of the test print I am working on. The piece will be PA-CF filament. With the Markforged, support would be layed in an accordion pattern under the cavity with no support under the center thru-hole. Bambu Studio creates a solid raft of support under the cavity including under the center thru-hole. I have tried every tweak of the settings I can and it always generates a full initial layer. Does anyone have any suggestions on how to get a better break-away style zigzag support like I would get out of my Markforged? I have top and bottom interface layers set to 0 and it still creates interface layers as well.

This is a test piece for more complicated geometries I print so yes, it does need to be in this orientation with the cavity underneath. Thanks for any help!

[CarbonForge]

I’ll offer a different approach that would still achieve what you’re asking for.

If you’re using a dual nozzle you can use PETG as your support interface material and set your support clearances to zero - it will give the best, cleanest support and also release perfectly with zero effort.

[lkraus]

I’ll assume you have Advanced settings active in Studio.

Try using one of the Tree styles and set Interface Pattern to concentric. Some support bases will be under the hole, but at least the interface layers should stay clear.

Similar model to play with:
test.3mf (41.0 KB)