Home Repair

secure lock for an old door?

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Hi Guru!

I have an original lock from my 1880 home on our front door. I think it is a mortise type? Anyways, the key for the lock is an old skeleton key, and we have concerns that more than one person may have a copy (including family members of the original owner and the caretaker). Even if we get all of the copies back, my hubby wants to install a new, modern lock barrel of some form or another into the door for security reasons. The interior knob is loose and wiggly too...

How can we get in a new lock without destorying the historical charm of the old mortise set? I know there are reproduction mortise sets on the market, but I haven't really seen any with modern keys. Can we cut a new hole for a decorative looking deadbolt? I'm a little confused by how locks go into the door in the 1st place...


Karen Smile
The knobs would have to come off then the lock mechanism would slide out of the mortise. If you put in a modern lock, you would have to cut a piece of wood that fits the mortise and glue it in. Then you could drill and install a new lock. There are lots of different styles available that look old school and would fit the charm of an older home. There are knobs that have a D shaped handle on the outside with a thumb latch.

There might be something you could buy that might fit the old mortise but I have found they never fit close enough to use the old holes.

Fill it in, wait a couple hours for the glue to set up, drill the hole (2 1/8" usually) for the knob assembly and the side hole for the latch (7/8" or 1" usually), and install the new assembly!
Thanks Guru! This'll probably be one of our first projects when we get in! I'll let you know how it comes out Smile

Karen Smile
One last thing...
If the hole on the face of the door (where the knob itself would be) is say 1" or 1 1/2" or not the correct size for the new knobset, then you will have to drill it out. The only way to do this is with some sort of jig. You can make one real easy or pay about $120.00 and buy a nice metal one. Here's how to make one...
1. take a scrap of wood about 12" long x 3" or 4" wide x 3/4" thick and using the correct drill, drill a hole through.
2. using 2 clamps, clamp this jig exactly where you want the new hole to go. Make sure you position it correctly using the supplied template that came with the knob set. Also you should be clamping another scrap to the other side so the hole will come out clean with out tear out.
3. now just drill through the template hole into the door untill you start going into the scrap on the backside.


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