2009-03-26

Lever Lock Guts

This lock had to be destroyed during replacement because the key was lost. I've already removed some of the levers from this lock. In total, there were 10.


8 of the lever tumblers are configured like this. There are two peices with teeth to join them together. This way, you can re-key them however you want. There are 7 different positions that are usable in this design. The Cut-out on the right side that's surrounded by two sharp points is the slot where the lever lock's gate is supposed to go. Until all of these are lined up perfectly with the gate, the lock will not open. The sharp points are there to make it difficult to pick or impression the lock, because they'll catch on the gate, making you think that you've picked this lever properly when in fact you may not have. It also makes it difficult to maintain tension on the bolt or gate to keep the lever in place while you work on other levers.


Not shown: Between each of the above levers, there's also a thin metal shim. This keeps the levers from rubbing against each other, but also makes picking difficult regardless of bitting patterns.

The remaining two levers are shaped like this. They're not able to be re-keyed, but you can stack them wherever you want in the lock. The oblong pivot hole (on the left side) also prevents one from using gate tension to hold it into place. This tumbler will simply fall past the gate once you stop manipulating it. Since there are two of these levers in this lock design, you would in theory have to pick both of them at the same time, and you'd have to do it only after all the other levers are perfectly aligned and held in place by lock tension. This design is also such that if you hit the upper or lower part of the slot, it will jam the lock and you'll have to release some tension and try again.


Here's the broken lock, mostly disassembled.


Here are all the guts. You can see the pile of shims in the lower left corner of this photo.


Unfortunately, the main part of the bolt including the gate were snapped off, so this lock is completely useless for practicing on or using. It did give me a look into some fairly advanced security features I'd never before seen in lever locks before, though.

Locks of this variety are most often found in safe deposit boxes. As you can see, it's often easier to simply use destructive force to open them if you don't have the key.

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