Puzzle boxes are small containers which are built with a concealed opening mechanism. They can range from simple boxes with one step to open them to large, complex devices that open in 30 or more steps.
LEGO is a wonderful medium to work with when designing these boxes as it allows for much experimentation and offers a lot of options for opening mechanisms. The three boxes in this tutorial are all 4×4 and open in one or two steps.
Due to the small size it was a fun challenge to try to fit as many tricks in as possible that still allowed a small compartment to fit in the middle. Inside each box is an open stud on which a small treasure can be placed. To give the boxes a coherent theme, each one has a wooden look but with a different pattern.
In building each of these puzzles I wanted to give each a different method of opening. This box is one which requires a special grip to be opened. You can only pull open the door by holding it on the two corners, otherwise attempting to pull does nothing.
This box uses gravity to keep it locked. One section of one of the sides must be pushed upward for the lock to be opened, allowing the door to be slid open.
This is a two-step puzzle that requires a hidden lock, located on the top, to be slid back. The box can then be opened with a push on a small section on the back.