Print-It-Yourself Puzzles

Currently Playing: Coincidental Twist - What other puzzles could be based on this "coincidental" geometry?

Print it yourself at https://oskarvandeventer.nl/Print-It-Yourself/. Buy at https://www.chewiescustompuzzles.com/puzzleshop/oskars-puzzles Read more at https://twistypuzzles.com/forum/viewtopic.php?t=40693 Coincidental Twist is based on a newly-discovered geometry that I called "Cube Sphere" ( https://twistypuzzles.com/forum/viewtopic.php?t=40234, see also https://discord.com/channels/862052650208329739/862059972904091678 ). When working on the mechanism of Inka Cube I stumbled upon this geometry, where the distance of a layer N to the origin is proportional to sqrt(N). This geometry has the surprising property that all corners touch the surface of a sphere, for any number of layers that the geometry is extended to. At every point where cut-planes intersect, it is not two but three cut-planes that coincide there. Usually, twisty-puzzle designers try to avoid such coincidence, as pieces tend to jam as these points. For this puzzle, it is a feature. The mechanism has a 3x3x3 core, and the outer pieces hang to the edge and centers of that core. The "coincidence" geometry is maintained throughout the outer shell, eliminating the need for extra "shells" pieces inside. Copyright (c) 2025, M. Oskar van Deventer. Frequently Asked Question: http://oskarvandeventer.nl/FAQ.html Buy mass-produced Oskar puzzles at https://www.puzzlemaster.ca/browse/inventors/oskar/ (USA, CA) and https://www.sloyd.fi/brain-teasers/inventors-designers/oskar-van-deventer (EU) Buy exclusive 3D-printed Oskar puzzles at https://i.materialise.com/shop/designer/oskarpuzzle, https://www.chewiescustompuzzles.com/puzzleshop/oskars-puzzles