BIG Corbin lock

[unbreakable]

Here's an interesting lock.




NOw here's where it gets screwy...






Oversized Corbin pins on top, two regular pins on the bottom.



Can anyone tell me the point of these two plugs(?)

Its a real stumper......

[dosman]

Wouldn't it allow an additional layer of master keying? So that you could have multiple master keys that would work on the lock? It would be interesting to see how it feels while picking.

[zeke79]

Wow, that is actually something I have not seen before. It does not happen here to much for me anymore as I expore alot of locks. This is one I have not seen before.

Info requested for sure!!!!

[Octillion]

dosman had it right, this core has what's known as a master keying ring. These operate very similarly to SFIC's, however both sheer lines simply operate the lock. Judging by the long driver pins, it looks like the master ring was not utilized in this particular lock, so it will operate and pick like any normal lock. I've seen master ring type locks pinned like this with long driver pins when the master ring is not used.

Picking these is very similar to picking SFIC's (when the master ring is utilized); they can be fairly easy, or nearly impossible to pick, just depending on the particular lock. Unlike SFIC's, a finch type torque tool doesn't exist, as there are no holes or other features on the bottom of the master ring (the finch tool torques the control sleeve of SFIC's using the holes on the bottom of the sleeve that are there for ejecting pin chambers). There is no real trick for picking these to one sheer line, other than a bit of luck.

[devildog]

LSS, p. 200, '8.3.7.1 Master Rings (MR)' for those that have it.

I knew what it was when I saw it, but had to look it up to refresh my memory as to what it's purpose was. Essentially, it allows masterkeying to be done without decreasing pick-resistance and also reducing the possibility of cross-keying.

For those that don't have LSS, from security.org:

http://www.security.org/Search/VerityDetail.cfm?ID=2101

[devildog]

oops, wrong link, here's the right one:

http://www.security.org/Search/VerityDetail.cfm?ID=2099

[Schuyler]

That's very interesting! Thanks for the pictures Unbreakable.

Now, does that look like it says "Borbin" to anyone else?

[What]

prolly a Corbin knockoff.

[UWSDWF]

nah.. its the curly's on the C

[unbreakable]

SWEET!!

I contacted the seller, and he's selling me another one that is keyed!

Plus, I found another in my box of goodies! Only its not a real corbin, its a knockoff......

I think I'll try picking one masterkeyed.

[raimundo]

these old corbin ring cylinders are often salvaged when an old hotel goes down, early twentieth century, to mid century I think, allow for security with master keying, often used when there are floor masters, managers masterkey, and other levels of access programed by the cut of the key.
The designation 'corbin ring cylinder' is common I think.

[unbreakable]

Cool, the guy I bought them from just called it a Corbin Big Bertha cylinder, but I don't know where he got that name from...

He seems really knowledgeable.

ring cylinder seems more likely, unless he was comparing it to he aunt bertha

[David_Parker]

This lock is for jail use most likely. Much like a mogul cylinder which is why it has top pins and ball bearings for bottom pins, and why its so oversized. Mul-T-Lock is coming out with one, and there are others. Yes, everyone is correct, the other 'ring' is for masterkeying, acting as a second shear line.

-Dave.

[zeke79]

Those "ball bearings" you see are shadows....... That is what threw me from identifying it in the first place too . It is how the lighting is in the pic .

[Octillion]

This lock is for jail use most likely. Much like a mogul cylinder which is why it has top pins and ball bearings for bottom pins, and why its so oversized. Mul-T-Lock is coming out with one, and there are others. Yes, everyone is correct, the other 'ring' is for masterkeying, acting as a second shear line.

-Dave.

There is no reason this would be from a jail. Maybe some jails use(d) them, I couldn't say, but these are not high security locks, and were never designed for jails, just for master keying systems.

I have a Corbin master ring lock with ball bearings, and it simply came from a college building, replaced with Best SFIC's. As far as I know it wasn't to lock anyone inside... The ball bearings are simply to reduce wear on the front pins, and do not add any extra security. I've seen these in other locations as well, like on doors to utility rooms, etc.