The Alchemist's Cube

A combination lock box with mysterious appeal

This puzzle box features 4 dials, each with 8 alchemic symbols. Line the correct symbols up to release the core, lifting the core out reveals a hidden compartment, perfect for storing your philosopher's stone.

Demo video https://www.youtube.com/watch?v=Lefe1lm4fOM

The core of the box is locked into place by 4 pegs that must slide through the keyways of the 4 inner wheels. Since the core can only move vertically, the inner wheels must be rotated so their keyways point upwards, only then can the core slide up and out. The keyways line up with one of the 8 symbols depicted on the outer dial, and you can choose which of the symbols you want, during assembly.

The puzzle box is fairly robust and the pieces fit together well, with no slack. My prototype box had a problem in which the combination could be guessed by feel due to the slack in the model. This problem was fixed with a number of features that make guessing the combination by feel very difficult. As an additional precaution, I have included a false keyway on some of the inner wheels, to introduce uncertainty for anyone trying to open it by feel. In my opinion, the false keyways are not necessary as it is already difficult to guess by feel, but they are available if you want them :)

Printing

All STL files should import into your slicer in the correct orientation.
I printed the body, base, and core in PLA with a layer height of 0.25 mm and 30% infill. You will need supports for the Body and the Core, but they are minimal. The Base does not require supports.

The rest of the parts: Inner Wheels, Outer Dials, and Decorations were printed using PLA with a layer height of 0.2 mm. The Outer dials were printed in duel-colour silk PLA and the decorative pieces were printed in tri-colour silk PLA. The Inner wheels and outer dials require supports as they have detail on both sides, but again, the supports are minimal.

Print List to make a cube:
1x Body
1x Base
1x Core
1x Core Decoration
1x Top Decoration
1x Top Trim (optional - choose your preferred style)
4x Inner Wheel (choose any combination of the two types)
4x Outer Dial Wheel
4x Side Wall Decoration
4x Edge Trim (optional)

----Update----

I've added some optional edge trims to cover up the edges a bit. Print 4 edge trims for the vertical edges and one top trim for the top. The top trim features 4 arrows that denote where the chosen symbol should be orientated. There is also a smooth version if you do not want marker arrows.

Assembly

The only extra tool you should need is some superglue.

Start by inserting one of the inner wheels through one of the holes of the Body. Check to see if can rotate without too much resistance, but also doesn't wobble around. Put a dab of glue on the outer dial and press it into position against the teeth of the Inner Wheel.
Be sure to line up the keyway with the desired dial symbol before gluing into place. The teeth of the inner wheel and outer dial should help align the symbol and keyway.

Make sure the wheels are pushed all the way into the dials, with no gap between the wheel and the inner wall of the Body. Repeat this for all 4 dials and continually check to make sure they all still rotate.

Next, run a dab of glue around the edge of the Base and slide it into the Body. It should pop into position with ease. The orientation of this part does not matter; it is symmetrical.

Next, glue the Core Decoration onto the Core. Be sure to use lots of glue and orientate the decoration so that there is a small gap between the Core and the ridges of the decoration. This gives the user something to grab when lifting out the Core.

Finally, glue on the decorative plates. Use the gap around the dial and the body edges as a guide. Note that the top decoration is slightly different from the walls. The top decorative panel features the 4 alchemic symbols for Earth, Fire, Water, and Air. This is an optional feature to help identify which dial is which, in the case that they are all printed in the same colour. I found it easier to have the Core inserted while gluing the decorative panel on.

With all that gluing complete, simply stash your philosopher's stone, or any other alchemic secret you might have, line up the chosen symbols, insert the Core, and scramble.

Enjoy your combination puzzle box, and please remix :)

P.S. I hope to be uploading a video soon