I could avoid this for the last 20 years or so but now I need to build BIG models out of styrofoam slices, stack them together and then sand them into the final shape manually. Piece of cake I thought, but…
How do I prepare my model in Rhino to get the slices for that? I know how to slice models and I know the section tools in Rhino8 but they only create curves from a specific height, not the whole section I need:
I can slice the model at the different sections and extrude it up or down (depending on the shape) but how do I get the curve that is needed for the middle section? I can do this manually, extract the whole section, create a mesh outline and extrude it, but this is a lot of work for complex models. Is there a way in Rhino (or grasshopper) to do this automatically?
I might:
Make a plane bigger than the object
Array the plane vertically at the slice height
Split the object with the planes
Use silhouette to get the outline of each slice
Project the silhouette to the lower plane of each section
Extrude the result upward the section height.
All I could type in one minute, gotta go now…
Thanks, but silhouette creates more than the curve that I need so I have to clean them first. That’s why I’m using mesh outline…
Tried to do this with Luban3D (which has a stacking feature). Doesn’t work at all.
The parts of the sphere should be covered completely…
Yes, there is a cleanup routine to get just the outer loop…
The only risk here is that the mesh outline, being facetted, may actually be inside the object slightly in some spots. If the mesh is fine enough, it probably won’t matter much, and if you’re sanding foam, probably not at all. You can always offset the outlines slightly to the outside. The procedure I outlined above works with MeshOutline in the same way as Silhouette.
SlicingMeshOutline2.gh (18.6 KB)
Thanks a lot, I tried it and it works. I’ll dig around in the grasshopper file when I have more time. 
