Since I posted that I’ve been able to make the tetrahedron and a (wonky, distorted) octahedron. I’ve been trying to make the tight-packed cube by stacking 5-by-5 squares and 6-by-6 squares alternately, but now that I look at the picture again I see I’ve been going at it all wrong. Off to try it again.
Update: Still can’t get that cube, but here are some pictures of other polyhedra. The icosahedron is hollow; the others are not.
Have you tried to make the second variety of cube I linked to—cut out from a tightly packed sphere lattice instead of a cubic lattice?
Since I posted that I’ve been able to make the tetrahedron and a (wonky, distorted) octahedron. I’ve been trying to make the tight-packed cube by stacking 5-by-5 squares and 6-by-6 squares alternately, but now that I look at the picture again I see I’ve been going at it all wrong. Off to try it again.
Update: Still can’t get that cube, but here are some pictures of other polyhedra. The icosahedron is hollow; the others are not.