Solid Fills

I am trying to experiment with hatch and clipping plane options. The first problem I encounter is when extruding a rectangle (with no solid option) and cap it. Then I offset srf. When I use the clipping plane it doesn’t show that it is hollow inside. Why is that?

If i want to use a hatch, solid fill/poche, in the section cuts of the walls, how do I do that? How can i capture that in 3D. I’ve seen someone do this and have wonder since then how to do it.sectionandhatch.3dm (103.7 KB)

it ‘fails’ because your two cubes are two separate cubes. You cannot shell an object in Rhino without removing 1 face AND keeping the two as 1 object… you can with a mesh in Rhino. Mesh both cubes, invert the inner cube and join the two meshes into one.