In this Instructable I will explain how I made the "unseen maze" as a challenging gift for my brother last Christmas.
The maze is made from solid maple, and has a compartment inside that contains the real gift. The compartment remains locked until the challenge is completed.
The goal is to have a marble travel through two separate mazes until the marble becomes the "key" to unlocking the not-so-secret compartment. The challenge is that the maze is not visible from the outside, and one must use sound, gravity, and patience to complete....or go crazy.
It has been over 9 months since I gave this gift to my brother. When asked how he's progressing, the answer is usually, "I'm not really sure if I am making progress, or just going backwards."
Hopefully he'll unlock it one day....
In the figures below, I show the CAD assembly I used as the design baseline (shown in transparent so you can see the internal maze), and the second figure is the finished (but not assembled) product.
Step 1: Model/Design the Maze
I'm an engineer by trade, but also by hobby. It took me months to simply dream up this idea, but only 2 days to build the final product.
To ensure that the design would work, and also to work out the maze itself, I used CAD software to design the maze before cutting any wood. The maze is constructed from 7.5" x 7.5" x .75" square boards, stacked 4 high for a total of 3" height.
Shown in the figures are exploded views of the mazes, compartment area, and lock/key assembly.
There are two mazes included in this; one on top, and one on bottom. The marble is inserted into the top maze via a hole in the top, then the marble must travel through the first maze, where the exit of the first maze (on top) is the entrance to the bottom maze. Once the bottom maze is completed, the marble falls between what i call the lock and key. The lock and key are two pieces of wood that are not otherwise connected without the marble--the marble completes the connection and allows the key to actuate the lock--unlocking the compartment.