This is a small puzzle box that is intended to contain a nickel. I have uploaded three different models. Each model requires the use of a different si...zed small ball. The intent is that you can choose the model size to match whatever size small plastic ball / round bead you happen to have on hand. Part of the trick involves the plastic bead to see the full solution and how the box works you can take a look at the video included in the photos or click on this link. https://youtu.be/UGnz6Ecnk24
The model is sized to use a 10-24 screw and nut to hold the puzzle together. I start with a 1.25 inch long screw and cut it to length after I see how thick the puzzle is. The puzzle thickness varies with the ball diameter.
I also include the model files for a 3D printed mold that you can use to make your own small balls from hot glue. There is more information on the mold and molding process in the video. The mold prints should be printed with a finer resolution (I used .1mm layers).