Print-in-place Cryptex with a twist (post-processing and demo).
Key combination, size and various options can be adjusted (OpenSCAD source on GitHub). Any characters may be included in any order (or duplicated). The number of digits can also be adjusted simply by adding extra rows to the character array. This demo includes a riddle to solve.
A one layer gap separates a thin support area for the rings. Separate rings after printing with a sharp edge in a rolling motion. Beware of z-seam alignment, it will give the game away (use random).