Wooden puzzle. Laser cut.

thingiverse

To solve the puzzle, you must remove (release) the ring. I did not write down the solution itself, it is not very simple, I have to think about it, but it is 100% =). Plywood 4mm. You can also 3 and 5 mm - this layout is not very tied to the thickness. A bit of glue. Clothesline 40 cm. You can simply tie knots at the ends of the rope so that they do not go into the holes. 3cm ring - anyone will do, can also be cut from plywood.