Union Overlapping Volumes simply doesn't work

[S3D-r]

Application Version

5.2.1

Platform

Win 10

Printer

Creality CR-10 Max

Reproduction steps

Put two bodies on platform, make ém overlap. Select Union Overlapping Volumes . Select Remove Mesh Intersection. Slice. Preview.

Actual results

There will be an outer wall in the edge of the overlap.

Expected results

The overlapping volumes are supposed be treated as it was a single body. The correct outcome should be infill.

Checklist of files to include

• Log file
• Project file

Additional information & file uploads

Overlapping bodies.zip

[GregValiant]

Thanks for the report.
I couldn't get it to work as I expected either.
I exported you model from Cura as an STL and then merged the combined model using MS 3D Builder. As a workaround this looks acceptable. I don't know how your real models would work out though.

[S3D-r]

Yeah, your workaround is commonly known, and sometimes it works, but not always: the workaround may raise other issues.

[nallath]

This is intended behavior. See the extra info that the setting guide gives:

[GregValiant]

Jaime van Kessel (@nallath) I get this with Overlapping Volumes turned off.

and this with it turned on.

And this one with Remove Mesh Intersections enabled

Am I missing something? I don't think I've ever gotten models to slice like either one of those in the Setting Guide.

[S3D-r]

This is intended behavior. See the extra info that the setting guide gives:

OK... So, Cura is just missing the feature where separate intersecting meshes would be printed as one mesh. That would be useful feature, and many other slicers have it.

[Diiescher]

While playing around with https://www.thingiverse.com/thing:4093734 I came to TXY2PROPRO2EXY3SE_Jammy_Dodgers_TOP.zip

"Remove Mesh intersection" looks bugged to me also

Even Cura 5.4.0 seems to struggle with it. Or what is the red and white line?

[GregValiant]

This is in 4.13.1. The models on the left are separate meshes and the model on the right are the same two models but I merged them in MS 3D Builder. In both of these images "Alternate Mesh Removal" is turned off. In all the images "Remove Mesh Intersection" is turned on.

This is the same project in 5.4.0.

This time I turned on "Alternate Mesh Removal".
4.13.1

5.4.0

With this test both versions produced nearly the same result. It isn't what I expected though. With AMR turned on there are skins on every layer of the overlapped models. I thought that was odd.

The bold warning at the bottom of S3D-r 's screenshot seems like an attempt to cover the situation I created. It might be a verbiage thing but the results just seem odd.