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How do keys work? Explained in one Gif

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Re: How do keys work? Explained in one Gif

#21

Post by jlgreco »

usaphp wrote: post #3

I wonder how did people come up with a structure like that...back in the days people were smarter.

The modern pin tumbler lock is more or less an evolutionary step along a long line of lock designs. The basic principles of all locks are basically the same; you have some sort of hidden configuration (in this case, the lengths of each pin, or in the case of a much more primitive warded lock, the positions of the posts) which must be matched by the key for mechanical movement to be possible.

How you combine those elements takes some intuition, but if you really look around you at the world today I don't think it can be said that this sort of creativity and insight has been lost to history. We're building some pretty wild stuff these days.

Re: How do keys work? Explained in one Gif

#22

Post by borlak »

gggggggg wrote: post #5

That's a great way to explain it. However, can anyone explain how lock picking works, that GIF makes it seem like it would be very difficult. On TV at least they do it in a matter of moments.

SquareWheel explained it very well.

As for the difficulty, you'd be surprised how easy it is. I started picking a few weeks ago for fun and I've been able to pick your basic store bought locks within a couple minutes with the hook tool (where you have to lock each pin individually).

There is another tool, called a 'rake', that tries to set several pins at once -- it basically has several jagged edges, much like a key. With rakes I can beat these locks in a matter of seconds, and I'm a newbie! I'm working on the lower end of locks, but even still, it has made me more wary of home security.

Re: How do keys work? Explained in one Gif

#23

Post by tadfisher »

jjclarkson wrote: post #13
jjclarkson wrote: post #6

This design is a good visual for why lock bumping is fairly easy on most residential locks. http://en.wikipedia.org/wiki/Lock_bumping

On residential locks the tolerances on each pin's traveling cylinder are loose enough to allow you to apply shearing force on the pin by holding the lock tight (as if trying to open it) and quickly bump each pin up so they land on the salient edge of the entire cylinder block and avoid dropping back into a locking position.

Wikipedia disagrees with you, albeit without a citation:

"High-quality locks may be more vulnerable to bumping unless they employ specific countermeasures. More precise manufacturing tolerances within the cylinder make bumping easier because the mechanical tolerances of the lock are smaller, which means there is less loss of force in other directions and mostly pins move more freely and smoothly. Locks made of hardened steel are more vulnerable because they are less prone to damage during the bumping process that might cause a cheaper lock to jam."

http://en.wikipedia.org/wiki/Lock_bumping

Re: How do keys work? Explained in one Gif

#25

Post by TallboyOne »

tptacek wrote: post #18
vinhboy wrote: post #16

Earlier quoted context omitted.

what exactly is that little dirt stain that moves from cylinder to cylinder supposed to be? is it supposed to represent tension or something?

It's the currently binding cylinder. With the right amount of tension applied via the wrench, one pin binds at a time, which is what allows you to set the pins one at a time.

What's the difference in feeling where he's 'testing' which one's the binding cylinder or not? Is it just a tiny bit more 'grainy' harder to push or something?

Re: How do keys work? Explained in one Gif

#26

Post by Joeboy »

SquareWheel wrote: post #11

Locks are a relatively simple a fun mechanism to play with. Lock picking can be explained similarly. It's essentially simulating that key by popping the pins up to the shear line (the horizontal plane) and applying tension via your tension/torsion tool so the pin doesn't fall down. Then move onto the next one. If you get all pins to the shear line, the lock opens. It's also a pretty cheap hobby to get into. Though th…

A few years ago I went and bought myself the cheapest Yale type lock I could find in order to teach myself to pick it. After repeatedly failing I took it apart and discovered some of the pins had recesses that were designed to defeat this kind of attack (I think they're called "spool pins"). I never managed to put it back together again, and that was the end of my lock picking career.

Re: How do keys work? Explained in one Gif

#27

Post by Cushman »

SquareWheel wrote: post #11

Locks are a relatively simple a fun mechanism to play with. Lock picking can be explained similarly. It's essentially simulating that key by popping the pins up to the shear line (the horizontal plane) and applying tension via your tension/torsion tool so the pin doesn't fall down. Then move onto the next one. If you get all pins to the shear line, the lock opens. It's also a pretty cheap hobby to get into. Though th…

It also comes in handy more often than you'd think. Picking real-world residential locks is usually a Bad Idea even if you're allowed to, but with a little practice anyone can learn to open cheap wafer locks (like you find on desk drawers) or padlocks in seconds with nothing more than a couple of bobby pins.

Like when I cleverly managed to mail my apartment keys to myself, including my only mailbox key...

Re: How do keys work? Explained in one Gif

#28

Post by tptacek »

TallboyOne wrote: post #25
tptacek wrote: post #18

Earlier quoted context omitted.

It's the currently binding cylinder. With the right amount of tension applied via the wrench, one pin binds at a time, which is what allows you to set the pins one at a time.

What's the difference in feeling where he's 'testing' which one's the binding cylinder or not? Is it just a tiny bit more 'grainy' harder to push or something?

The binding pin won't bounce up and down when you actuate it with the pick. The non-binding pins won't offer any resistance at all. Also, when you manage to get the binding pin to the shear line, the tension wrench will sometimes give up a little more rotation.
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