How to extrude open polysurface to get a solid?

Western Hemisphere land.stl (1.1 MB)
I have an open polysurface (green) that I am trying to extrude to the base plane (blue), but it only extrudes the outer edges leaving me with a hollow polysurface (black). I would like a way to make this a solid, closed polysurface. I have tried joining the existing polysurface to the extruded portions, but it is unable to join for some reason. Similarly cap does not work because the polysurface is not planar. Is there a way to extrude the surface so that it is solid, or a way to close the extrusions with the polysurface so that it becomes solid?


Western Hemisphere land.stl (1.1 MB)

The file you uploaded contains a mesh, not a polysurface.

It looks like the uploaded file contains your results. It would be helpful if the inputs are also uploaded.

How much experience do you have with Rhino?

Do you have experience with other 3D software? If so are you assuming Rhino is similar?

1 Like

Minimal experience with rhino. But the file I uploaded is just an exported .stl file of what I’m working with (my apologies). For this file, I used MeshtoNURB to make the mesh a polysurface, however, it is still open and therefore hollow. Is there a way to make the open polysurface closed so that it is solid.

Hi -

Please just upload the 3dm file.

the whole file is too large to upload to the server.