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Richard Feynman: Physicist and Safecracker

16/10/2018 wheel combination safe

The Nobel Prize-winning physicist, Richard Feynman, began safecracking while working on the United States’ atomic bomb project at Los Alamos during the Second World War. The hobby fascinated him and he devoted a whole chapter of his autobiographical memoir to stories relating to safes he’d cracked.

Security Risk

Codenamed The Manhattan Project, the atomic research station at Los Alamos brought together the greatest minds in America to figure out a way to unleash the energy of the atom in the form of a bomb. You might have thought that security would be a major issue – but in the early days important documents were kept in filing cabinets that were only locked with a simple padlock.

Pin and Tumbler

There wasn’t much entertainment out in the New Mexico Desert, so Richard Feynman taught himself how to pick the basic pin-and-tumbler locks on the filing cabinets with a small screwdriver and a bent paperclip. He would leave the filing cabinets open in offices he had visited and raided for files. After 18 months, top brass caught on and ordered wheel combination safes that boasted 1,000,000 possible combinations.

Cracking Safes

Even these safes weren’t as secure as the manufacturers claimed. Feynman quickly worked out that you didn’t have to hit one of the hundred numbers on the wheel exactly in order for the bolts to line up. This reduced the number of possible combinations to about 8000. Upon further examination of the mechanism, he realised he could see the second and third numbers of the combination if he ever got to glance at the safe when it was open. With this information and the imprecision of the wheel, he only had to try about twenty combinations to open a safe.

In many cases, he didn’t even have to use that combination of memory and trial-and-error. Feynman found out the manufacturer’s settings for the safe and tried it on every safe in the building. One in five of the world’s most eminent scientists, working on America’s top-secret nuclear bomb research programme, had not bothered to reset the combination!

In case you are not a Nobel Laureate and you need to regain access to your safe quickly, we can help. Give us a call on 01603 812613 or email us on

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Read Richard Feynman’s account of his years working as an atomic physicist and part-time safecracker in his memoir Surely, You’re Joking Mr Feynman.