Japanese Box with Secret Compartment

This is a traditional Japanese secret box. Can you open it?

It’s actually simple to solve. I’ve designed a pattern on the box to make it a bit more challenging. We tend to think the squares are part of the top and bottom, but they’re actually part of the sliding walls.

This puzzle features 4 sliding walls, with the top and bottom connected, hiding the secret compartment.

To open the box, you’ll need 7 moves. The key is to discover which panel moves first. This creates a gap that allows the rest to be moved sequentially. After 7 moves, the secret compartment is revealed.

Printing Tips:

• Layer height: 0.2mm is sufficient.
• Use variable layer height for better results on rounded edges.
• Reduce the speed for outer walls during the first 5mm to improve exterior quality.
• Sliding walls require supports. Using PLA and PETG as support interfaces ensures easy removal and excellent results.

Assembly Tips:

• Attach the top and bottom pieces. They feature rails that only allow correct alignment.
• Each sliding wall has a letter for identification.
• The base rails indicate which wall to place in each position.
• Start by inserting wall D halfway.
• Continue with C, then B, and finally A.
• Push all walls until they touch the adjacent one.
• Repeat this sequence until the box is fully assembled.

Enjoy!