Well, just the one. Edges? Zero. Vertices? None. Oh dear! Oh well. The spheres are disappointed and one is angry. 3D shapes have faces (sides), edges and vertices (corners). Faces - A face is a ...

3D printed holder mounted to bike wheel, fitting precisely 38 magnetic spheres around its perimeter. Tedious math? Not if you make OpenSCAD do it. Off-the-shelf components are great; the world and ...