Broken bosses from inventor to Rhino

[Anonymous]

Hello. 

I am doing a 3D  model from inventor that has bosses, and when I open the file in rhinoceros (from a .step exportation) the surfaces from the bosses are messed up. 

Can someone help to avoid this happening.

Thank you  

[SharkDesign]

Have you got a screenshot?

What does messed up mean?

[Gabriel_Watson]

Similar thread here:
https://discourse.mcneel.com/t/import-solid-stp-file-in-rhino-problem/119425/7

There seem to be issues with STP imports in Rhino that force people to repair the geometry:
"In the case of STEP import, isolate each solid, Explode it, RebuildEdges (default settings), and Join.
If it’s still a Closed, solid, polysurface, you’re good to go.
If it has naked edges or other problems, there will be some cleanup to do."

Or simply import as a DWG format instead.