Interlocking Puzzle Piece Flat

I wanted to create a printable part that could take the place of the plywood that makes up the CupCakeCNC. I chose to make a repeating pattern of interlocking puzzle pieces. However, a single layer of these puzzle pieces would not be strong enough for anything but a toy. I added a set of holes that would allow offset layers of puzzle pieces to be bolted together, forming a stronger whole.

I expect to be starting into making corner and edge pieces. I think it would be possible to laser cut these.

The current version is 40mm x 40mm x 4mm corner-to-corner-to-corner. Tongue-to-tongue it is 60mm. The holes are 4mm in diameter and spaced 20mm apart.

Earlier attempts at 60mm x 60mm x 5mm pieces all had to be aborted due to head crashes with ABS shrinkage curling up the corners and breaking the raft from the build surface or, in one case curling up the entire acrylic build surface. This might have been due to the use of an Infill Solidity (ratio) of 1.0

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