Surface from imported step file (steel ring)

Hi there.
I am new to Rhino, and was wondering:
I would like to make a surface from a “deformed” steel ring frame, I have made in solidworks.
How should I do that?

It is a frame for a chair, so has 10 different radii.

Is it best to export from SW to a step file or what?


Hi Kim - the starting point would be to bring in the geometry via SW file or Step, yes. Hard to say what’s next without more information, though.


Hi Pascal.
I understand that it is hard without more information.

I found this picture that shows what I would like to do.
I now have the frame made in Solidworks (picture to the left), and would like to make a surface around the frame, to make the padding for the chair.

Can I somehow extract the geometry from the frame, or do I need to freeform surfaces around it, by hand?

Hello - you can extract curves in various ways from the frame surfaces - ExtractIsoCurve, DupEdge, Project new curves onto the frame, Section curves… You can ExtractSrf faces from the frame polysurface (as I assume it is), Copy or OffsetSrf these…you can set custom construction planes to the existing or new geometry if that helps - all of this will no doubt be useful but when it comes down to it, you will need to know how to create new surfaces at some point.