He used the CNC router a lot for making Diamond Case.
Well, I cannot tell you the details of how he used the CNC router because it might be the hint to solve, he-he.
There is a point to pay attention to, especially for woodworking lovers. Please look carefully at two diamond-shaped buttons on the puzzle.
As you can see in the picture below, there are several options to cut diamond shape on timber. Juno wanted to cut the diamond shapes like A. Actually, B is easier for cutting than A but he thought that A looks better.
Well, what do you think?
Yukari
* Pluredro Shop: Diamond Case – secret puzzle box
