The tetrahedral-octahedral honeycomb is a quasiregular space-filling tessellation (or honeycomb) in Euclidean 3-space. It is composed of alternating regular octahedra and tetrahedra in a ratio of 1:2.
Using magnetized blocks is a helpful way to explore and design with honeycomb structures. The challenge with the triangular faces of the tetrahedron and octahedron is that it requires three magnets per face in to hold the faces together in the proper alignment. That adds up to 24 magnets for each octahedron and 12 magnets for each tetrahedron, which gets expensive!
These blocks use contours to rotate faces into proper alignment, requiring only one magnet per face to maintain contact. That, and they are much more visually interesting than flat surfaces!
Note that the contours do create small gaps between the blocks, so the honeycomb is not purely space-filling.
The holes are designed for 1/8” x 1/16” cylindrical magnets. Clean the holes out with a hand -turned 1/8” drill bit. Most magnets will hold press-fit in place, the odd loose fitting one will require a dab of glue. Polarity should be opposite between octahedrons and tetrahedrons.