Trapped Ball Puzzle

thingiverse

Inspired by the Hanayama Marble puzzle I received for Christmas - and having cracked the code on what the puzzle was about - I set out to create my own variation using Fusion 360. It turned out to be a fantastic challenge. You'll need to print two copies of the 'Hexoid' slice (which is not a cuboid, I know) and two copies of the sphere slice. *I believe these are actually 'cubic trisections' - check out this item on Thingiverse for a clearer explanation.* The Hex pieces can be printed without support, but I recommend adding a few mm of brim due to their small initial footprint. Spheres are always tricky in FDM printing. Orienting them with the 'wings' facing up produced nice edges on the complex curve at the expense of the gnarly area where support was. Setting the support angle to around 52º minimizes the footprint of the support. As always, you'll need to pare back, file or sand the sphere at the support for smooth operation. A word about tolerances: The sphere parts should slide past each other smoothly. If they work out too sticky or stiff, you can either do a bit of sanding to ease the surfaces, or print at 90% flow. The Hexoid parts are fairly loose, so they shouldn't need any adjustments. The puzzle, when assembled, will feel loose but won't fall apart.