Shrouded Keyway

[Theist17]

How do we pick locks? That is the fundamental question.

We all agree that, in order to manipulate the pin tumblers of a pin tumbler lock, one must bind the cylinder. We accomplish this through the use of tensioning tools. Ordinarily, these are angled pieces of steel, inserted into the keyway.

A shrouded keyway, similar to that of this American Padlock, only more obstructive to the keyway. This would deter tensioning by standard methods. This could still be defeated by filing down a key blank, but restricting the proliferation of that blank could provide further obstacles.

The only weakness I can think of for the end-user would be the inherent structural weaknesses in the key itself. The shoulder of the key would need to be quite narrow in order to bypass the shroud on the cylinder. This leads to a higher amount of shearing force on the shoulder, thus leading to a higher number of breakages. All keys could be made of a stronger material, or possibly reinforced at the shoulder. I'm not yet sure how this could be accomplished, but it seems doable.

A quick sketch of the proposed key blank is below.

Bah. It would be below, and not all jacked up if I could figure out how to make it work the way I want to. Anyway, you can see how the should is narrowed down a good deal.

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[vov35]

http://www.lockwiki.com/index.php/Medeco_KeyMark

/you reads.

[Theist17]

I may not have been clear.

What I mean is that the cylinder can't be turned unless the key blank makes it past the shroud. That's why the blank has such a gap between the blade and the bow. The Keymark's keyway is nothing like what I'm talking about. What I'm proposing isn't anything which would prevent access to the pins. It would only prevent tension from being applied with a single tool. The plug wouldn't turn any farther than maybe an eighth of an inch if you managed to pick it.

[Theist17]

Actually, if you look at the American keyway I posted up there, just imagine it turning counter-clockwise, and you'll have a good idea of what I'm saying.

[vov35]

1) have you ever filed a keyblank down that small? it breaks
2) I could get a screwdriver and jam it in the middle of the keyway and turn it.

now if the bitting somehow disconnected from the key handle, you could prevent manipulation during the application of tension.

[criminalhate]

It sounds like your talking about a ward before the pin tumbler part?

maybe I'm not getting what your explaining

[Theist17]

Man. Why couldn't I have just said it like that? That's pretty much exactly what I mean.

[Theist17]

1) have you ever filed a keyblank down that small? it breaks
2) I could get a screwdriver and jam it in the middle of the keyway and turn it.

now if the bitting somehow disconnected from the key handle, you could prevent manipulation during the application of tension.

If you check the original post, I made mention of this weakness. Still not sure how to get around that. Good point with the screwdriver. However, I have an idea on how to deal with that. It requires some obscurity for the security to work effectively, though.

There is a check pin in the extreme rear of the plug, seating in a sleeve. This sleeve has a flange on the bottom which is seated in a slot in the bottom of the plug. Until the check pin is pushed to the rear shear line, the plug will not rotate.

Any thoughts?

[vov35]

I'm imagining a steel tool that looks kinda like a 2 in 1 lever pick opening this cylinder with no problem.

[Theist17]

Is this an existing tool? Or would you have to make it yourself? The idea here is to prevent the standard vectors of picking attacks, i.e; commercially available tools with no modifications.

I can see what you mean about that tool, though. Cool idea.

[vov35]

...the lever two in one pick came about after the lever lock...
I'm pretty sure that if this lock wasn't too retardedly obscure tools would begin to be made.

[Oaklandishh]

I think I understand what you are saying, but I don't see how this could make it harder to pick unless the key is so thin at the neck, that it couldn't possibly turn the cylinder. Also those Americans can be picked both directions, its just requires some fancy tension wrench work AFTER the lock is picked.

[LocksmithArmy]

Actually, if you look at the American keyway I posted up there, just imagine it turning counter-clockwise, and you'll have a good idea of what I'm saying.

have you ever herd that picking locks backwards it often easier than picking forwards... thats y we have plug spinners... i purposfully pick locks backwards often... INCLUDING 5200S...

the wards on the 5200 are only there to prevent the key from turning the other direction... picking in the opposite direction with standard tools it simple... you just cant turn the plug without moving your tensor to the center of the keyway to "bypass" that ward...

a simple way to beat your wards would be to insert a "T" shaped tool to turn the plug after you pick it... picking is still the same since the plug WILL move minutly with standard tools, and minutly is all you need.

if youd like i can pick a 5200 backwards on cam for ya to show you what i mean... you just have to turn the plug 270 degrees instead of 90