Simple puzzle with a ring

I rembered making a puzzle as a project with friends in high school (more than 20 years ago), but was not able to find any informations on it (pictures, blue print, …), so I decided to do it from scratch from what I remembered we did on our milling and lathe and this is the result.For the puzzle, you need to print 1 body, 1 ring, 2 cylinders and 2 discs. Only the body need support. In my case, I prefer to print each kind in different color. You will also need 30 cm of some string. In this case I