Hi all,
I have a Corbin mortise lock I can't figure out remove and am hoping someone here can give me some insight into the issue.
The door mechanism has a grip handle with a thumb push latch on the outside and a knob on the inside. The mechanism looks as though it should slide out the edge of the door, except the mortise lock is retaining it inside the door.
It appears as though the mortise lock is used to disengage both the deadbolt and door latch at the same time.
The issue is the key is missing and the lock unusable. I simply lock the door by pushing the pins in on the edge of the door and then use another door as the entry.
I have removed the screws that should be retaining the mortise lock but it refuses to unscrew at all. I took all the hardware of both the outside and inside, but the mechanism is still retained in the door by the mortise lock.
There are no more screws anywhere that I can see to allow the lock to rotate out of the mechanism.
Any ideas? I sure could use the help.
I'm not sure but it sounds like you removed the small screw that holds the cylinder in. If so then that is all that should be holding it in. If the cylinder still doesn't unscrew then use a pipe wrench or something else to get a grip on the cylinder and turn it. If you can find a key that fits into the cylinder that may work to turn it out.
Let me confirm, as mgmine assumes, that by mortise lock, you mean the key cylinder which does indeed screw into the mortise lock case....and with everything else removed, including loosening the key cylinder set screw 3 or turns, a lock of this vintage, presumably not having been serviced in 25-30 yrs, can be tough to remove. Look at the rim of the cylinder to see if others have had to use a pipe wrench or channel locks to install/remove it. These cylinders are easy to cross-thread if forced on in that manner, will require forcing off as well.
Thank you for the suggestions. I may not have explained myself as well as I should have:
I am not able to unscrew the mortise cylinder from the lock. Although I have removed the faceplate retaining screws at the top and bottom, the face plate does not seem to want to come off. From viewing other posts on this subject I am lead to believe I need to get the face plate off in order to access and loosen the set screw that may be retaining the cylinder. I found a key for the lock. It's very worn and has to be jiggled to get the pins to the shear line. With the key, I can slightly get the handle grip latch to move. The deadbolt will not move in the least. Although I don't know if it's possible, I suspect it's the deadbolt that may be seized somehow in the faceplate, not allowing me to pry it off. Is this possible? There were no prior signs of anyone trying to crank the cylinder out of the lock.
I did use a small pipe wrench gently on it but only got the brass cover to rotate, not the cylinder itself. It still seems very solid, suggesting the set screw may be still firmly in place. I simply cannot access the set screw, since it appears the face plate won't come off. It last functioned properly about 10 years ago. See pictures 19 and 20 at: http://www.baldwinhardware.com/suppo...structions.pdf
I don't want to destroy the threads in the lock by ripping the cylinder out with a pipe wrench. I just can't understand why the face plate won't come off, allowing access to the set screw.
I absolutely appreciate everyone's response.
Look at picture 19 is the set screw still installed? Is so then you need to remove it, if not then you need to do what ever you can to turn the cylinder out. If there isn't any sign of a set screw or a hole for one then I can't imagine how the cylinder is being secured.
Some of the really old mortise locks didn't even use a faceplate, but if the screws you removed were tiny, like
#6-32 X 1/4, then those were the faceplate screws allright.
(But if they were bigger, like #12-24 or #12 wood screws, those were the lock case screws, and you don't have a faceplate.)
Has the door been re-finished/painted/caulked around the faceplate? Can you clearly see the edges?
I tried prying up what should be the face plate, but the whole lock seemed to move with it.
There were two screw holes located next to each other. One of the holes had a #12 screw that was about 2 long. I assumed this held the cylinder in. I was still unable to budge the cylinder after removing the screw, which suggests the retaining screw is still intact somewhere. All visible screws have been removed (the plate retaining screws and the 2 screw). There are no more screw hols visible, unless this is a cover plate and the set screw exists under the face plate. I will take a closer look at everything shortly. I just don't want to damage the door or the threads on the cylinder hole.
I am told the lock is an original 1927 lock. I was able to pry the end of the face out slightly. It does not look like there is a face plate covering any set screws.
I did spray some wd-40 into the lock cylinder and into the two holes that had the #12 screws in them. I'll try tomorrow, hoping something has loosened up.
There is a tool that most locksmiths have, designed to fit around the mortise cylinder and persuade the cylinder to unscrew.
As to the retaining screw issues, most of the retainers you speak of do not work like this in these brands of wooden door mortise locks.
The retainer screw hold a V shaped block that sits into the threaded cylinder body preventing it from unscrewing. Removing this screw usually tightens the block against the cylinder. You might need to put the screw back in and tighten it to allow the V block to separate from the threaded cylinder allowing the cylinder to unscrew.
I could be wrong, but I don't remember Corbin using the retainer block as described by Global, and at any rate, you describe 2 holes, next to each other, opposite the cylinder, with one 2 screw in the hole nearest the cylinder, (the other hole being used for an opposite handed door). The block retainers usually employ one centrally located screw to retain a cylinder on either side of the lock case.
The ring around the cylinder makes it very difficult to get a channel-lock or similar on the cylinder to unscrew it, but if you crush it in getting the cylinder out, your smithy will have a variety of replacement rings.
Oh, and most mortise locks of this vintage did not have a separate faceplate, (sometimes called a scalp or front).
Tags: corbin, mortise, lock, face plate, mortise lock, pipe wrench, cylinder unscrew, lock case, mortise locks, screw still, screw that, access screw, cylinder still
