The 3D printed lock is based on the Bank Raid puzzle in "Leonardo’s Mirror & Other Puzzles" by Ivan Moscovich. The puzzle was inspired by the 2-dimensional world of "Flatland: A Romance of Many Dimensions" by Edwin Abbott Abbott.
The pieces of the lock can slide up, down, left or right. They have studs on the back so that they can slide along the channels in the base plate. Once the top is glued in place the four corners are fixed but the sides of the frame are still open. The aim is to free all four pieces from the frame.
I printed at 80% length and width, keeping the thickness unchanged.
The video shows how to solve the puzzle