February 7, 2021
Description
This is a Hoffman packing puzzle.
https://en.wikipedia.org/wiki/Hoffman%27s_packing_puzzle
It is puzzle where you (try to) pack 27 cuboids with 3 different side dimensions into a cube with equal sides of the sum of the cuboid dimensions.
A parametric fusion file is included, so it can be made to whatever size. Theoretically there should always be a solution for the 3 dimensions you choose (evil grin).
Keep in mind that for an interesting puzzle, the 3 sides of the cuboids must each have a different size and the sum of the sides must be less then 4 times the smallest size (x+y+z < 4*min(x,y,z)). It will still be solvable, but it will be easier.
I added 0.2 mm play in the design, so scaling is not recommended. Just change the parameters in the Fusion file if you want to scale the design. I posted a slightly smaller version here: https://www.thingiverse.com/thing:4753370
If you are making this as a gift, the solution is on the wikipage, so you can package it.
You need to print the cube, the lid and 27 cuboids:
-1 x 'Cube.stl'
-1 x 'Cube lid.stl'
-27 x 'Cuboid.stl' or 3 x '9Cuboids.stl'
I printed them in 3 batches of 9 in different colors, hence the stl with 9 cuboids.
There is also a single stl file with all parts if you have a big build plate.
If you are looking for a similar more challenging puzzle, check out: https://www.thingiverse.com/thing:4754202
which is the Knuth version (it has 28 instead of 27 cuboids).
License:
Creative Commons - Attribution