During our testing sessions we stumbled upon an issue. The magnet would sometimes pull in pieces that it wasn’t supposed to from neighbouring squares. Moreover the pieces would sometimes repel each other when placed too closely. Eventually we narrowed down the problem down to the pieces simply being too light.

Several ideas passed through our heads: perhaps we could make the pieces bigger? But that would make moving pieces between squares harder. Add more magnets? But that would further exacerbate the problem. Maybe put a metal rod inside the pieces? Sounds complicated.

Eventually in the spirit of Occam’s razor, I figured out we can just set the infill during 3D printing to 100%. Teamwork makes the dream work.