Hi all, I was asked how the hinge of the Marble Cage was done, in particular the clearances etc. I thought that it would be interesting to share this with the community: so here it is! This hinge is not very usual (well, at least, I've never seen it elsewhere) probably because it's quite difficult to make it without 3D printing (interlocked parts) and also because it was born from my obsession of having identical and symmetric parts (obsession not so widely shared, unfortunately ). It works in all materials I have tried: Stainless Steel, White Strong and Flexible and Transparent Detail. Basically, this hinge is made of 4 torus (I guess I should say tori), two for each parts, but you can add more of them if you wish. On each part, the 2 tori are perpendicular and linked by a cylinder. The diameter of the wire is 2 mm and the clearance is 0.5 mm. This means that the internal diameter of a torus is 3 mm and the external is 7 mm (5 mm for its axis) Check this image, it should help to understand the dimensions and the position of each element (dimensions are in green, the rotation axis in red). This video, show the hinge is action. As usual, comments are welcome!