Planet Arduino

If you head out into the real world and start twiddling knobs on random safes, you might find yourself being hauled away by uniformed police. A safer pastime might be playing with your own puzzlebox at home, which is precisely what [thediylife] has done with this build.

The design implements a basic safe-cracking game, in which players try to guess the combination to the safe in a series of rounds. Input is via a rotary encoder, hooked up to the Arduino Uno inside. This project really wins because the finish looks so amazing. The safe is constructed out of 3mm MDF, which is lasercut to shape — an easy one to whip up in the average makerspace. The interface is fleshed out with a small OLED screen and some LEDs, while a servo acts as the lock which holds the door shut. When you see the underside of the face plate with components hot glued into holes you’ll really pale at how clean the business side ended up.

It’s a simple build, and one that would make a great party game with a prize hidden inside. We’ve seen other puzzle-box builds before, too — like the GPS-based reverse geocache build. Video after the break.

Puzzle boxes are great opportunities for hacking. You can start with a box which was originally used for something else. You get to design circuitry and controls which offer a complex puzzle for the players. And you can come up with a spectacular reward for those who solve it. [thomas.meston’s] Dr. Hallard’s Dream Transmission Box, which he created for an original party game, has all those elements.

The box was a broken 1948 National NC-33 Ham Radio purchased on eBay after a number of failed bids. Most of it was removed except for the speaker. The electronics is Arduino based, so most of the smarts are in the form of code. Potentiometers and a switch provide the mechanism for players to enter codes. And when the correct code is entered, a relay triggers an external smoke machine and turns on a laser which illuminates a party ball, rewarding the victors. And of course, there are also sound effects as well as a recorded message.

We weren’t kidding when we said puzzle boxes make great hacks. Here’s one which ignites fireworks, one made only from discrete components, and a valentine based one which makes your significant other work for their gift.