Turner's cube

myminifactory

I watched Brun's YouTube video and highly recommend his channel. The classic puzzle he presented to machinists is also available on the CNCCookbook website. I approached this exercise like a machinist, carving out cylinders from nested cubes, but soon realized the inside surface of the cubes was not ideal. To overcome this challenge, I had to boost my CAD skills, slightly, to create a spherical inner surface. This is indeed a superior result that's more practical with 3D printing than with subtractive manufacturing. Either the inner cubes are immobile or the interior of the cube isn't a perfect sphere. A skilled CAM lathe user might prove me wrong, but I'm confident in my design. I created this model in OnShape and it's available for viewing: https://cad.onshape.com/documents/7578e4f3ee04d5c50b0f9ba6/w/8a71c61a2a394945cbf93649/e/0664345b59a74f88c0c675d9