Machine Can Pick any Masterlock Padlock

(Video Link)

Jessica Bethune, Aiswarya Kolisetty, Jessica Noglows, and Rob Sobecki are students at the Olin College of Engineering. For a class assignment, they built a machine that can figure out the combination to any Masterlock combination padlock. The LockCracker tries every possible combination, spinning the dial until it's successful.

via Wired

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For those of you trying to view from somewhere Sony is blocking the video, a revised version can be found at There's no licensed music so it is viewable anywhere.
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As a hall monitor with nothing better to do, I tried my lock's combination on every locker on the top row of the hall I was 'guarding'. There may have been 100+ locks and I was able to open 4 of them.
These crappy locks have a tolerance of like 4 or 5 numbers, meaning that if your combination is 1,1,1 you could still open your lock by dialing 3,3,3 or 39,3,0 so where you might think you a protected by great odds (40x40x40?) it is truly much, much smaller. I doubt that there are even 40 combinations to begin with as it would require too much retooling and handling at the factory. I could be wrong...
Any way, the easiest way I found as a teen to open them was with a flat blade screwdriver: Using the locker as your anvil, give the screwdriver a whack with your fist while aiming at the top of the number wheel's edge. With one solid knock, the wheel will be loosened enough to wedge the blade underneath, twist and pop the dial off. Now aim the blade between the center shaft that held the dial and the case of the lock. Another good hit with your fist and EVERYTHING inside the lock falls apart and to the bottom of the lock, releasing the latch. (BTW, the shim method is far superior to 'my way' and even leaves little to no trace that you were ever there)
Why do I share this? Mainly, because my locker was broken into multiple times and the schools forbid you to use a better lock to protect your belongings so you end up schlepping 50lbs everywhere (all books, lunch, etc.. If the locks are proven obsolete, perhaps someday they will improve and kids will have at least some security and privacy (from other students).
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You don't have to brute force a Masterlock combination lock. You map the stops on the cylinder to get the third number and then can backtrack the others from it. There are only 80 possible combinations once you have the third number. Even if you have to try all of those combinations, you're looking at less that 20 minutes start to finish. I've done it twice with locks we've found around the house.
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These guys are classmates of mine -- I'm a sophomore at Olin college and they made this last semester as their project for a class called POE (principles of engineering). There were a ton of awesome projects implemented for the class, with the only restrictions being that every project had to have a mechanical, electrical, and software component.

Other projects from that same semester included a CNC cake decorator (which also got a little press:, an automatic sundae machine, a mechanical implementation of pacman, and my team's (not so useful, but awesome) dancing kinetic flower sculpture:
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