Solid closed polisrf having faces with different colors

HI

Since using RH7 i have been witnessing a unusual behavior when obtaining solid with entities mostly imported from other cads.

some of the solid obtained with booleans or by joining surfaces togheter are closed watertight polisrf but the some of the surfaces are inheriting colors from the source object. as a result i have a solid that behaves moslty normally but it does have some weird behavior when it comes to shading behavior + the waht commad is telling me its not a valid polisrf.

on the other side the _showedge command is not showing any issue with naked or nonmanifold edges.

I tried to explode polisrf, change color of all single surfaces and join them again but nothing change.

what does it depend on ? how can i erase all inherited properties and get a regular solid ?

thanks .

Rhino 7 has the possibility of having per-face colors inside the same polysurface. This also applies to imports from other programs via STEP etc. that have the same capability. To remove those colors, use the command _RemovePerFaceColors.

However, that is not the cause of the object being invalid - something else is. Run Check on the object and it might give you some more (cryptic) information on why it is bad. Probably some out of tolerance edges causing bad joins.

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Given that this is an invalid polysurface these faces might have inverted normals and showing the back face colour.
This usually happens as a result of edge tolerance problems (as @Helvetosaur pointed out) and is quite common with file import from other solid modelers.

HI Norbert, I know what you are talking about but this was not the case you mentioned , i checked normals and were all same direction…the _RemovePerFaceColors suggested by Helvetosaur solved the issue.
thanks

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