Old Schlage dual-deadbolt

[too-picky]

Hi,

I bought an old door for my house--it's old, so I buy old doors. The door came with a nice patterned knob on a skeleton lock, just like most of the doors in my house.

The odd bit is that there's a deadbolt on it near the glass window--security feature which prevents criminals from breaking in as they might cut themselves. The deadbolt doesn't have a throw lever like all modern ones. It has a tumbler and key-hole on both sides. The really queer thing is that neither lock will throw the bolt alone, but both must have a proper key in them simultaneously.

It is literally a deadbolt with a key on both sides.

I'm wondering has anybody has come across one of these? I thought it might be a hotel lock where both sides needed to be unlocked to join two rooms, but they are keyed the same. Perhaps too, the bolt may be the wrong one and somebody just scabbed together parts during the depression era (earlier this year). It is made by Schlage to be a double lock as far as I can tell. Puzzling little beastie.

Thoughts and ideas welcome.

[averagejoe]

Hmm, thats really weird. Usually with a double deadbolt one side alone can open it. Perhaps something is broken inside?

[FarmerFreak]

I'm 99.999999% certain that the lock isn't installed properly, or I guess it could be broken.

On the back of each cylinder there is the tailpiece that goes through the bolt and rest against the opposing tail piece. One of those tailpieces was installed 180 degrees the wrong way.

[too-picky]

Nothing broken, except I've removed the pins from the "inside" portion.

I'll check the tailpieces, but it seemed to have only one way it would go in.

It would be neat to get it working properly if possible, although I'd leave the inside key in it in case of a fire; maybe key the outside as a master for both sides?

[too-picky]

Yep, it was the tailing. If it gets twisted around, then it locks and both need to be turned at once. That's cool. Thanks.

I still can't figure out what it was used for. Why would schlage go through the expense of having a key on both sides, especially when they have the same key? Maybe it was salvaged and re-keyed from a hotel? I can't think of anything else or any other reason to key both sides, and from a safety point of view, I rather dislike it.

[averagejoe]

Its a bit higher security. If you have glass beside your door somebody cannot break the window and unlock your lock with the thumbturn.

[keysman]

FarmerFreak is right .. the timing is most likely off on your deadbolt. To fix this:
Open the door.
Remove the lock cylinders from the door ( leave the actual bolt installed)
Flip the dead bolt to the locked position ( use a flat blade screwdriver if necessary)
For the exterior lock cylinder:
1.Hold the cylinder up to the exterior portion of the door.
2.Turn the tail piece towards the leading edge of door the until it stops.
3.Reverse the turning direction until the tail piece is vertical ( apx. ¼ turn)
For the interior lock cylinder:
1.Hold the cylinder up to the interior portion of the door.
Repeat steps 2,3
Assemble lock , test , collect money

[too-picky]

Already did that (or similar, I just guessed and retried) and it works now.

Thanks.

[keysman]

Yep, it was the tailing. If it gets twisted around, then it locks and both need to be turned at once. That's cool. Thanks.

I still can't figure out what it was used for. Why would schlage go through the expense of having a key on both sides, especially when they have the same key? Maybe it was salvaged and re-keyed from a hotel? I can't think of anything else or any other reason to key both sides, and from a safety point of view, I rather dislike it.

It also keeps someone who entered (Window?) without a key from exiting with your big screen TV.
Safety is an issue and in many community’s Double deadbolts are not allowed on new construction.
At least 1 manufacturer makes a “ key retaining “ interior cylinder... It holds the key when locked from the inside, to allow for fast easy exit. You just take the keys with you when you leave.

[too-picky]

Cool. So many locks, so little time.

[cledry]

Double cylinder deadbolts are also used on gates where you don't want someone reaching over or through to open the lock. They are used where a broken window would allow access to the thumb turn of a single cylinder lock. They are very common.

[too-picky]

Hey,

I think you're up late as I just replied to you and got this one--we're both online right now.

Right after my last post I found some of these new in the store. I guessed that you are correct, and now you've confirmed it. The one I have seems to be pretty old, so the market seems to have held for a number of years.

Thanks for your input on both threads as they clarified well!