Support at intersections of merged mesh

[Spark908 0]

Hello! Reaching out today on the forums about an issue that I'm struggling to solve with supports being placed where they shouldn't be. I have two complex meshes that have been imported as obj files and merged together. When slicing them, support is scattered inside of the object on the lower quarter of the sphere. 

 

Using a square eraser on this object gets rid of support that is necessary on the outer surface of the sphere. I've trued custom eraser plus cylinder eraser without any luck. Any idea of how to get rid of the support that is growing inside of the bottom quarter of this sphere? Any input or ideas would be greatly appreciated!

[Spark908 0]

Here is the attached 3mf file for a full view of the object I'm trying to slice. I've always had an issue of Cura incorrectly wanting to put support at the intersections of complex merged meshes for dual extrusion, and I'd love to try and figure this out.

DEBegleri.3mf

[GregValiant 1,259]

Cura marks invalid surfaces with a polka dot pattern.  Your model has several areas with flipped normals.  

When I try to repair the model the entire thing disappears.

 

 

So one reason you can't get rid of the support is because the "top" surfaces down low in the model are calling for support on their upper sides.

Both models are in need of serious repair.

 

Here is what I get when I tried to bring a support blocker in.  I've never seen this before.  The entire world turned inside out.

 

[Spark908 0]

16 hours ago, GregValiant said:

Cura marks invalid surfaces with a polka dot pattern.  Your model has several areas with flipped normals.  

When I try to repair the model the entire thing disappears.

 

 

So one reason you can't get rid of the support is because the "top" surfaces down low in the model are calling for support on their upper sides.

Both models are in need of serious repair.

 

Here is what I get when I tried to bring a support blocker in.  I've never seen this before.  The entire world turned inside out.

 

Thanks for the reply. I'll see about altering the pipeline in which these are created, but in further tests, I found that the issue does not come from the dual extrusion surfaces at all!

 

I have sliced another object with no alterations. Just a pure uv sphere from blender, only to find that the supports are Still in the internal part of the sphere, while only a single extruder is being used. From this screenshot, I believe the issue not to lie with the dual extrusion itself, but with Cura's handling of the object somehow. The normals are all correctly oriented. what might be going on here?

[Spark908 0]

Seems to be an issue with tree support, as I switched the support to normal mode, and the supports inside of the sphere are completely gone. 

[Slashee_the_Cow 272]

6 hours ago, Spark908 said:

Seems to be an issue with tree support, as I switched the support to normal mode, and the supports inside of the sphere are completely gone. 

Seems like something you should submit a bug report about. Make sure to include a project file, probably the demo sphere to illustrate that it will happen even with simple shapes.

 

I don't think the person mainly responsible for tree supports is very active on the forum but they are in the GitHub repo so they should see it.