How come Key A can open Lock A. Key B can open Lock B. But not lock A. And key C can open all the locks? Doesn’t that mean A and B should be able to open each other?
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So, the shape of the key, and the parts inside a lock correlate to a numbered code. Physical math. In fact, your key may have it’s code written on it, usually 5 or 6 digits.
A number like 6, could also be 4+2.
So you have two locks, each with five pins (numbery bits)
[6] [6] [6] [4+2] [6]
[6] [4+2] [6] [6] [6]
Now, we have 3 keys, A, B, and Master.
Key A is [6 6 6 4 6]
Key B is [6 4 6 6 6]
You could then have a Master Key coded to [6 6 6 6 6] that would open both. And yes, there are a couple other combinations, like [6 4 6 4 6] that would also work. It’s a little more complex/precise than that, but that’s the idea.
Because of that, setting up doors for a master key system makes them much easier to pick as there are multiple succesful paths, with it getting exponentially so with each extra key/lock you’re tying in.
Depending on the lockset, different pins of varying heights are used. The master key is set to work with the initial pin configuration, followed by the other keys interacting with the additional pin discs used to build them.
I used to build locksets for our medical facility. We had three master lock setups: one for the main facility; one for the pharmacy (and related storage areas); and one for the mental health wing. Even though I’m not a locksmith, I performed the function of a locksmith, including using lockpicks to open cabinets that the staff had lost keys to. I never tried to open safes though.
Also, how do keys work?
Locksmith here.
In a standard household lock, there are usually 5 chambers that hold 5 sets of a top and bottom pin. When the key enters the lock, it raises these sets of pins to each particular height so that the space between the top and bottom pin lines up with the turnable part of the lock (the shear line). If even one of those sets doesn’t line up properly, the lock cannot turn.
A master keyed lock works by having a top, bottom AND middle pin in at least one chamber. This makes two different lines in the chamber. Meaning 2 different keys can raise the pin to 2 appropriate heights, since there are two spaces.
A master (or middle) pin in all five chambers exponentially increases the number of different keys that will work in each lock, though it is still common practice to have all three pins in each chamber, even if you only want one extra key to work.
Determine master key possibilities, numbers etc gets a bit complicated and requires above an ELI5.
You want to cleanly bite off a piece of carrot.
You have seven teeth top and bottom to do the job.
Each tooth needs to meet the tooth above or below for a successful bite.
If any one tooth is too long, it will hit the upper tooth before the other 6 teeth finish biting. Fail
If one tooth is too short, 6 teeth will finish biting but the 7th tooth doesn’t reach the shorter tooth. Fail.
Now consider drilling a tooth size hole through the carrot.
Now when you bite, 6 teeth will bite properly and the long tooth doesn’t matter because there’s no carrot there due to the hole. The bite just needs 6 teeth for a good bite.
It’s the carrot that made the difference with the hole.
Oh, Hell! I’m not five yet and I can’t take this to conclusion.
Will eat an apple instead.
Are master keys not called skeleton keys anymore? Sorry if this is a stupid question, but I always liked the designation “skeleton key”. Or is that only for buildings?
you might have heard of “lockpicking lawyer” you might have heard of “Devient Ollam” (“Ollaf”).
if you havent, go binge some stuff, i feel like you would enjoy it.
[https://www.youtube.com/watch?v=aVPSaKLKHd4](https://www.youtube.com/watch?v=aVPSaKLKHd4)
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