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Comment by Alupis | Hacker News Reader

This seems to work on only the most basic of locks, and doesn't seem to address "Security Pins" or false pins (pins if you move, will seize the keyway), which will cause false sets, clicks, partial keyway turns, etc.

They can be really nasty for an experienced lockpicker to navigate, and will make all the same sounds and feel of picking a real pin. Most semi-advanced locks will have one or more of these anti-picking countermeasures in place.

As it is, it would be far faster to actually pick this lock instead of trying to reproduce the key.

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> This seems to work on only the most basic of locks, and doesn't seem to address "Security Pins" or false pins (pins if you move, will seize the keyway), which will cause false sets, clicks, partial keyway turns, etc.

I don't see why either of those are relevant.

A key in normal operation won't interact with false pins, and security pins (I assume you're talking about spools/mushrooms) act like normal pins to a key.

You would get a different sound from the different types of security pins, but even then - not that many and as you say, as its the legit key being recorded - security pins won't do anything than act like a normal pin in operation.

At least have an excuse for leaving the house with the radio blaring out now - security.

> You would get a different sound from the different types of security pins

I'm not sure that's true...it may be true, but it hasn't been looked into. Also 99% of security pins are in the driver pins which aren't the actual pins that are making the clicking sound against the ridges. Since there is a set of pins (key pins) between the ridges and the security pins that could also "dull" the difference security pins change the sound.

In the same vein, though, great locks can also use different springs for each set of pins which also may effect the sound.

If I had a know security pin lock at hand, I'd check it out as have a few contact microphones that are perfect to delve into something like this. Certainly with spectrogram and zoom in after doing high quality recording and soon see what sticks out. Of course would really need a lock in which you have each type of security pin and a normal pin and change that one pin and compare several unlocking. I'd be supprised that there isn't some distinguishing aspect due to shape changes in the pin altering how it responds to vibration. Yes the springs will have some influence, a small scratch in the pin barrel would have a small nuanced effect that with with right measuring, would show up. I'll put it on my winter project list, more so as it may open up the possibility of not even needing a working key and just inducing some sympathetic harmonic with the pin types to induce resonance that can be measured. Could be a fun winter this year.

Agreed. These features are only relevant to picking, not to inserting the actual key.

> the most basic of locks

Which is what, oh, only what the vast majority of the people out there have on their front doors.

I think his point is that if the method only defeats basic locks, there's no point because basic locks can be reliably picked with $20 of tools and a few hours of YouTube tutorials and practicing.

That's fair, of course, but the method is still interesting and novel, and may even have security implications if it can be evolved to target locks containing features beyond the basics.

> basic locks can be reliably picked with $20 of tools and a few hours of YouTube tutorials and practicing.

Not without spending time at the lock, performing an activity that is obviously criminal to any witness, and having to repeat that every time you want access to those premises.

And, also: a neophyte lock picker will likely leave evidence, like scratches. If you have a key that works, you can open the lock without any traces of picking activity.

I mean, not everyone lives in a city. Someone could spend hours picking the lock on my front door at night and no one would even see them.

Plus, in the majority of break-ins, does knowing how they got in matter? If someone broke into my house and stole my valuables, does the fact that they picked the lock make all that much of a difference? I mean, I'd almost be relieved they did that as opposed to something more destructive.

(For the record, I have security cameras, please don't pick my locks)

And sitting next to the doorknob holding your microphone while someone walks in is totally legit. You aren't going to get a clean recording while hiding behind the fence.

I have an esp32 board with a MEMS microphone embedded in it that's about the size of a quarter, and can be powered for hours with a watch battery. So yeah, I can get a clean recording while hiding behind a fence... I just won't be holding the microphone.

I don't think so actually. Even cheap padlocks have security pins nowadays.

Someone doesn’t watch the Lock Picking Lawyer.

A surprising number of padlocks have no security pins whatsoever, including most Master Locks.

And then there's always a Ramset.

I do watch Lock Picking Lawyer (great channel btw) and I've dabbled with lockpicking myself.

But maybe locks are generally worse in the US than they are here in Sweden. Masterlocks are infamously bad.

They don't seem relevant to this technique, which involves recording audio from a correct key.

Doubtful most cheap padlocks can be opened with a shim made of a soda can.

Or even a good disc detainer lock, like an Abloy or similar, whose noise is more related to the current disc position more than anything else.

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