A few weeks ago hacker Samy Kamkar showed the world how to easily crack a Master combination lock—the same kind used on thousands of school lockers—in eight tries or fewer. But who has the time for that? Thankfully, Samy has followed up with this wonderful 3D-printed contraption that does all the hard work for you, in about 30 seconds.

Samy encourages anyone to build a Combo Breaker for themselves, and has posted detailed instructions, as well a step-by-step video, on how to assemble the $100 worth of parts that went into its creation. You’ll need access to a 3D printer to create the frame, but the stepper motor, Arduino Nano that serves as this contraption’s brains, and other necessary components are all readily available online.


When left to its own devices the Combo Breaker can take upwards of five minutes to crack a Master combination lock. But if you’re willing to help it out by finding the first number on the dial that gives some resistance (as outlined in Samy’s tutorial from last month) the cracking process can take as little as 30 seconds. So if this little machine doesn’t encourage Master to fix the design flaw that makes its combination locks so easy to crack, nothing will. [Applied Hacking via Wired]