Spinning Puzzle Box

This is a puzzle box that uses nails as a locking mechanism. The nails are cut to fit into a channel in the box, where they can slide in and out of a hole. When the nails are out of the hole, they lock the lid in place. In order to open the box, you need to slide all of the nails towards the outside by spinning the box.

I prepared the nails by cutting four large nails down to 15mm in length (including the head). Then I filed the cut edge to round the corner a bit for easier unlocking.

IMPORTANT: You need to pause this print partway through in order to put the nails in place. Pause the print when the channel is halfway finished, before it is closed over. Carefully put the nails in place and restart the print. Make sure that your print head will not move directly over the part of the nail sticking up above the print! This could potentially damage the print, or your printer. I used Cura to slice this model, and Cura does a good job of keeping the print head from moving directly over