Wooden Puzzle Gift Box
Project Summary
I designed and built this mechanical puzzle box in December 2019 as a present for my best friend. Although I took inspiration from a few mechanisms I found online, I custom-modeled and fabricated all of the pieces for this project (and devised my own puzzles as well). The puzzles are solved in a linear fashion and are a combination of both logical and mechanical challenges. The box is comprised of 64 uniquely modeled components, but has approximately 130 individual pieces total. I used several rapid prototyping technologies in its construction and assembly, including laser-cutting, 3D printing, and various hand and power tools.
Puzzles - A Walkthrough
The initial box, locked.
Twisting the back-left foot releases a spring-loaded drawer containing a plate with the characters "532 \ ILY" and an allen key set.
Using the correct allen key, removing the two hex-head screws from the front left panel of the box to reveals a torx-head drill bit.
The torx-head drill bit fits into a screw attached to the leftmost gear on the front of the box. A rack and pinion system moves a latch on the bottom of the box, dropping a thin, cylindrical rod.
Inserting this rod into a small hole at the rear of the box releases a second spring-loaded drawer.
This drawer contains three gears, each engraved with letters A through Z in a different randomized order, and an additional odd-shaped piece of wood (a push-stick).
The piece of wood obtained in the previous step can be inserted into a slot on the left-hand side of the box (on the right in this image).
Pushing with sufficient force reveals a thin, flat piece of wood with rectangular holes (a sheath).
The sheath from the previous step, when positioned against the panel of letters on the back of the box, reveals encoded strings of letters.
Using the "532 \ ILY" plate from the first drawer to position the gears from the second drawer in the correct orientation, the strings of letters can be decoded.
Decoding the letter strings results in the phrase "ADD ME UP THEN PULL". Using the convention A=1, B=2, etc. and summing the letters in each word leads to values 9, 18, 37, 47, and 61.
Aligning the knobs on the front of the box to the numerical values obtained in the previous step enables the top panel of the box to be removed, revealing the keys to the lock.
Behind the Scenes
The base plate inside the puzzle box is removable, revealing the internal mechanisms of the box (pictured here).
Although not visible, the twistable foot (removed in the first step) screws up into the left drawer, preventing it from opening. The drawer is spring loaded against the blue 3D printed component in the center of the base.
The right drawer has a 3D printed hook mechanism (blue), which is nested with a spring-loaded, pivoting 3D printed hook (orange). The small rod inserted into the back of the box presses against the left side of the orange hook, releasing the drawer.
The sheath is positioned in the lower half of the box and held in position by a neodymium magnet. When the wooden push-stick is inserted into the slot on the left side of the box, the sheath protrudes from a slot on the right side.
Regarding the removable panel on the lid of the box (i.e. the subassembly with the five numbers knobs), each of the knobs has a keyed back, which, when rotated to the correct value, will allow the panel to be removed as described above.
