The ultimate challenge lock ideas

[mmicbride]

I am looking for some ideas for ways to prevent a lock from being pickable but still operate very smoothly the countermeasures I have currently came up with is the use of

2 part core
Spools
Serated pins
Threaded chambers
Counter milling in the chambers
T pins
2 part nesting pins
Maybe a pin that moves due to a magnetic key?

Any other ideas would be greatly appreciated.

[Jacob Morgan]

If you are interested in that sort of thing you might be best served by buying Pulford's High Security Mechanical Locks.

[mmicbride]

It is one to just see how tough of a lock I can make and submit it to a YouTube channel where he will attempt to pick it!

[kwoswalt99-]

Do something with that magnet idea, nothing else there he hasn't seen before.

[Squelchtone]

It is one to just see how tough of a lock I can make and submit it to a YouTube channel where he will attempt to pick it!

You mean he as in Bosnian Bill, who is a member here?

[Jacob Morgan]

If you are looking to throw a curve ball, you could try messing with how easy it is to apply the correct tension. Start with a 6 chamber mortise lock. Remove the plug. Remove everything from the 6th chamber of the shell. Drill the 6th chamber from above with a #30 drill bit all the way through. Then tap about half of the hole. Reassemble the lock, putting nothing in the 6th chamber. Drop in a detent ball and spring e.g., http://www.brownells.com/gunsmith-tools-supplies/handgun-tools/crane-tools/crane-ball-spring-kit-sku713035000-9849-25596.aspx?sku=713035000 into the hole that you drilled. Put a set screw into the threaded hole to hold the detent assembly in place. Use a longer set screw for more pressure if needed. The idea is that the spring tension will push the detent ball down and make a fine application of tension tricky. There is a lot of resistance to turning and that might cause one to either use not enough or far too much. It is not a constant or even linear resistance. Using a normal key it works fine, although one would suspect something was different when it snaps closed with authority.

The idea of a spring detent creating tension resistance is in an old post on this forum. I was not the first person with the idea. Someone on this forum proposed it years ago and then later on, four or so years ago, Kwikset filed a patent on it (and sat on it). But being that there is prior art the Kwikset patent would be difficult to defend. I did modify a cylinder accordingly and have not managed to get it open without the key since then. Not sure how practical it would be in daily use as the steel ball might wear down the edges of the hole in the plug and become less effective. Have not seen any Bosnian Bill videos in a while, but never saw him deal with this trick.

[mmicbride]

Yes Bosnianbill

[Silverado]

Lockpicking Lawyer had a dimple lock on his channel not long ago which had a magnet in one of the chambers. This seems like over-engineering but I just had a thought:
Get a steel T pin in the bible, mill out the chamber so the top of the T rests in the milling and sits flush with the top of the bible thus it is basically a driver pin that does not move...
Once you get that in there, use a neodymium rod in the cylinder so it actually out of the cylinder and through the shear line.
When it's closed it'll pull itself up toward the steel T pin in the bible.
The key would need a deep enough cut with a small neodymium wafer in that cut which would pull the rod down into the cylinder and out of the shear line.
To pick it, you'd have to put a neodymium wafer in there to get that particular pin. Exactly the way LPL did with the dimple lock.

To make it trickier, put a couple of those in there in the front pins...then some wacky threaded chambers further back with really high bitting, spools, serrations, and counter-milling.
Make sure the binding order starts with the first couple pins so those magnetic pins have to be set in order to set the rest of them.
If you can accomplish all of that, you've got one obnoxious challenge lock.

[HT4]

Lockpicking Lawyer had a dimple lock on his channel not long ago which had a magnet in one of the chambers. This seems like over-engineering but I just had a thought:
Get a steel T pin in the bible, mill out the chamber so the top of the T rests in the milling and sits flush with the top of the bible thus it is basically a driver pin that does not move...
Once you get that in there, use a neodymium rod in the cylinder so it actually out of the cylinder and through the shear line.
When it's closed it'll pull itself up toward the steel T pin in the bible.
The key would need a deep enough cut with a small neodymium wafer in that cut which would pull the rod down into the cylinder and out of the shear line.
To pick it, you'd have to put a neodymium wafer in there to get that particular pin. Exactly the way LPL did with the dimple lock.

To make it trickier, put a couple of those in there in the front pins...then some wacky threaded chambers further back with really high bitting, spools, serrations, and counter-milling.
Make sure the binding order starts with the first couple pins so those magnetic pins have to be set in order to set the rest of them.
If you can accomplish all of that, you've got one obnoxious challenge lock.

If I am following this correctly, you propose a magnet embedded in the key that pulls a pin down (like the Avocet). If so, consider this: I think that a key that takes advantage of the repelling force of a magnet seems much harder to simulate than one that exploits magnetic attraction.

[Jacob Morgan]

Was asked in a PM to post a photo regarding the detent trick to make applying tension more challenging.

It is a normal 6 pin mortise cylinder. The pins and the spring from the 6th chamber are removed. Here is is assembled. A flush set screw would be more elegant than the pan head screw used here, it was just what was in the junk box. How to make it was in a prior post in this thread. Here it is assembled:



Here it is with the screw removed. The detent ball is a larger diameter than the pin hole in the plug. It only protrudes into it the plug a little bit, maybe 1/4th of it rests in the pin hole in the plug. When assembled the spring pushes down on the detent, and that makes dialing in the right tension challenging. It goes very quickly from not enough tension to set a pin to way too much tension. One may have to go with a long screw or use two detent balls to get the pressure right.



It may be confusing that the detent is in one of the pin chambers. It is easier to fabricate that way as holes are already there, but holes could be drilled anywhere thorough the shell and plug to create the same effect. If a lock used set screws to begin with to cover the top chambers (I've seen some Euro-Cylinders that used them) then it would be hard to spot the modification in a challenge lock.

[Silverado]

If I am following this correctly, you propose a magnet embedded in the key that pulls a pin down (like the Avocet). If so, consider this: I think that a key that takes advantage of the repelling force of a magnet seems much harder to simulate than one that exploits magnetic attraction.

That's a great thought. Wouldn't one be able to use a pick to just push that pin up though? What I'm saying is if the driver pin is steel or some magnetic material, is stationary, and the key pin is a magnetic rod that will attract to the driver pin when the key is not inserted. For the neodymium rod to move out of the shear line it has to be pulled by another magnet (on the key) down and away from the ferrous driver pin holding the neodymium rod inside the shear line.
I thought of that because if the key pin needs to be raised up to push the driver pin out of the shear line, a pick will do the job. If the key pin has to be pulled down into the cylinder to clear the shear line a pick will not pull it.

[HT4]

That's a great thought. Wouldn't one be able to use a pick to just push that pin up though? What I'm saying is if the driver pin is steel or some magnetic material, is stationary, and the key pin is a magnetic rod that will attract to the driver pin when the key is not inserted. For the neodymium rod to move out of the shear line it has to be pulled by another magnet (on the key) down and away from the ferrous driver pin holding the neodymium rod inside the shear line.
I thought of that because if the key pin needs to be raised up to push the driver pin out of the shear line, a pick will do the job. If the key pin has to be pulled down into the cylinder to clear the shear line a pick will not pull it.

No, not if you did it right. Just take the Avocet mechanism and reverse it, with the pin being magnetic (as opposed to normal steel). The cap that's at the top of the avocet mechanism would be at the bottom, blocking any attempt to physically pick it.

[Silverado]

Oh! So the "key pin" would be immobile and attract a magnetic rod down from the bible, into the shear line. To move it you would need a magnet on the key to repel that rod up into the bible to clear the shear line. That is quite devious. And to figure out that is the way it works pretty much requires disassembly or prior knowledge. Evil...I like it.

[HT4]

Oh! So the "key pin" would be immobile and attract a magnetic rod down from the bible, into the shear line. To move it you would need a magnet on the key to repel that rod up into the bible to clear the shear line. That is quite devious. And to figure out that is the way it works pretty much requires disassembly or prior knowledge. Evil...I like it.

Exactly. And I think it would be hard even if you knew what was there.

[GWiens2001]

I love the creativity here. Really like that idea.

You could make the key like the Miracle Magnetic Liquidonics lock. Then mill a channel from the shell through to the plug, just short of the keyway. Then there is nothing in the keyway to give away that the lock has been modified at all.

Gordon