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 used braided nylon cord like this one [https://www.amazon.com/AXLIZER-Braided-Lifting-Aluminum-Projects/dp/B095JL8XNC/.](https://www.amazon.com/AXLIZER-Braided-Lifting-Aluminum-Projects/dp/B095JL8XNC/.) I advise you to use a 2mm diameter cord since the holes are 3mm. If you go for the braided nylon cord, you will need a lighter to burn the tip a bit.

The assembly goes like this :

1. slip the string through the hole of one disc and make a knot (or more if it is a low diameter string). This way, the disc can not esacpe from the string.
2. now put a cylinder
3. and now the body with the ring already on it (it's cheating to let the ring already outside :p)
4. another cylinder
5. the last disc and make another knot. The all should be keep on the string by the knots

Now you can play and try to get the ring outside of the puzzle !

I think you can use it to present with a real ring if you scale it properly, but that could be a little mean :p