Intersection between two surfaces and a polysurface

Hi forum,

I am new to Rhino and 3d modelling, please excuse me if it’s already answered, but could not find a solution.

I am trying to get the solid contained within those two blue surfaces, when cutting the pink polysurface. Can you give me some hint? I’m quite lost and blocked at this point.


Maybe try the command CreateSolid? All surfaces must fully intersect. You should get multiple closed volumes, some of which you can delete.

Thank you. Already tried, but I only see that the execution “finishes” and then I see nothing. As in, no result at all.

Can you post the file?

If your pieces are equally spaced along the pink polysurface, I’d try closing that polysurface, then running the Contour command to generate curves at your needed spacing, then Offset those curves to build your sections. Or, I may be all wet.

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After more coffee, disregard the step to close the polysurface. Not needed. :upside_down_face:

You could also Split the pink surface with all the blue cutting surfaces, delete the parts you don’t want and Cap all to make solids. But I have a feeling they may not fully intersect, which is why it’s failing.

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Sharing the file here, thank you guys. The blue ones are parallel, but the pink one is crossing them at different heights.

Wing.3dm (3.1 MB)

Split was the command, which gives me the right chunk in the pink surface, but how can I close it to make a solid? Surface from curve should do the trick right? Would you use that or would you follow a different approach?

The reason why you can’t create solids is that your wing’s “sharp” edge is actually open (zoom in).

You will need to close that in order to create solid slices - either you can put a skinny surface in there by for example lofting the two open edges, or fix the original wing profiles so they are actually closed before creating your wing main surface.

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Great! I see now. That wing is actually a model I’m taking as reference, my objective would be to get the wing ribs. Thank you, I’ll close them!

The ‘upper’ end also has a problem that needs to be fixed…


But if al you want is sections on the other end, you might be able to hack something together without fixing the upper end…

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