What am I gonna do about this door?

I need carpenter advice.

My back door’s doorknob is broken. The screw that holds the inside knob on the lock is stripped, and is likely to just drop out (which it has, in fact. Fortunately, it has not been lost).

Now, the latch is not really important because there is an independant bolt that has been installed above the knob that actually locks the door shut. So even a dummy knob would work, since it would only be needed for pulling the door shut from the outside.

The problem? The lock mechanism of the existing knob also includes a deadbolt (painted over) that was apparently operated by a skeleton key or some such. It’s an old lock, obviously, and it’s all in one piece with the latch mechanism. Therefore, when I removed the knobs and locks to replace them with a standard set, I found the whole side of the door hollowed out to accomodate it. It’s about 7" in length.

I really don’t want to buy a new door. But how the heck am I going to replace the knobs and latch (or patch it) with that big hollowed-out portion? None of the standard, modern locksets accomodate such a situation.

I probably could fix it if I knew just how to approach it. But I’m at a loss. Anyone ever come across something like this before?

Remove the entire lock and knob set and cover with brass or steel plates. And drill a new hole through the plates. The scusion plates on the new lockset should give you enough securty to keep someone from removeing the screws own the outside. Or you can use securty screws on the outside.

What you have is known as a mortise lockset (the slot is a mortice).


if the mortise is nice and square:
Get a block of wood the same size and shape as the mortise, and glue it in place. Use wood dough (filler) to fill any small gaps.

if the mortise is not nice and square (more likely), use BONDO (or other such plastic to fill the hole. Slowly. Carefully - do not apply more than 1/4" at a time (if you could remove the door from the hinges and orient it mortise-up, it’d go more quickly.

DO NOT use wood dough for such large build-ups. Just don’t.

Either way, you now have a solid structure - select a latchset, follow the instructions (read the instructions while you’re out - you will need a hole saw and a large diameter drill (speed-bore types work well, and are cheap)

good luck

happy heathen, that’s sorta what I thought when I looked at it. I think I might be able to cut a “cookie” out of wood and make it fit the slot. Then, I assume the rest would be like putting a lock into an uncut door (which I’ve seen done, and I think I’d be able to do it okay).

A little advice on the Bondo, though. If I understand you correctly, I should fill the entire mortise with Bondo? I’ve never worked with the stuff before. Will I then be able to install the new lockset (or more likely, just a dummy knob) through the Bondo’ed area?

Thanks for the advice. I don’t know if I can remove the door from the hinges, since half the house seems to have been painted over for years. But I can definitely see the value in working at it from that angle.

I appreciate your thoughts.

If just the set screw is stripped you can buy a new one screw at any hardware store. If the threads on the knob are stripped you could:
•Cut new threads in it with an inexpensive tap. This would work well if you have one of the old brass knobs.
•Buy a knob, new or used, at a hardware store or antique/junk store.
•Replace the knob with a little used knob from some little-used closet in the house. Then use epoxy to glue the defective knob onto the knob stem of the seldom used closet door.
Sorry, I don’t see any way you could employ duct tape to make that last method any quicker or cheezier. :wink:

SQUINT’s ideas could work - or take the knob to a machinest to cut new threads (if you’ve never done it before, I wouldn’t go there)

also, the lockset you have was made in the 100,000’s in the 1920’s - 1940’s (I think). You could go to a building materials re-cycling place (if local) and pick up a replacement for a couple of dollars)

Bondo is an old trick to build-up massive chunks of missing wood (usually from dryrot).

It’s the stull used for body work - generally pink (if you must know, it is a polyester resin matrix) - it is very easy to work with (wear gloves!!!) - kind of like thick batter when first mixed, hardens in a coule of hours.

Make sure the mortise is clean before proceeding.

If you feel comfty with working with resins, you could do the combination trick (I would): cut a chunck of wood which will fit easily into the mortise, slather it with bondo, slap it in, and, yes Duct Tape it in place.

come the morning, use ordinary wood-working tools to smoth off any bumps.

What you now have is, essentially, a solid-core door - lockset installation is nice and simple (just make sure the two holes are alighned properly - the latchset will include a template to ensure that they are)

well I am late for this and I see everyone has covered the topic well :slight_smile:

have fun! is not really such a bad job all in all. It just sounds much more of a headache than it really is.


These responses are definitely giving me ideas on how to salvage this door.

That sounds about right. The house was built in the 20s, so this is one old door, hence my reluctance to replace it and destroy the charm of the original accoutrements (or if they aren’t the originals, then charming older accoutrements). The house is full of this kind of thing, including cut glass doorknobs on the first floor doors.

The knob and the mechanism are not completely shot, but they’ve definitely seen better days. If I can find another mortise lockset, I’d prefer to go with that, just to maintain the integrity of the period. Fortunately, I live near New York City, where anything on earth can be found if you know where to look. And I’m sure I know a couple of guys who might know a guy…You know what I mean…?

I’ve run into this problems more times than I care to remember. You have several options if you want to keep your existing lockset. You can find replacement knobs that run around $20 at your local hardware store. The most common that I’ve seen are brass or glass. You can also find porcelain knobs at flea markets that come in all colors.

Crown City Hardware offers knob sets and reproduction locksets, but they can be pretty expensive.

Cumberland General Store has replacement mortise locks and knob sets that run around $25.

I don’t know what the spindle looks like on your door, but the ones I’ve worked with had 3 holes at each end to adjust for varying door widths. Check the other knob. Usually, all you have to do is use a different hole for the good knob and that will cause the other knob to be aligned to a hole that isn’t stripped. If the screw is stripped also, e-mail me and I’ll send you a new one. They just tore my family home down, so we have old doors coming out our ears.

Thanks, I’ll check out those links when I have time. Our spindles are as you described. It’s the screw that’s stripped, and the inside knob looks like it had been pried with a screwdriver or something at one time. I may investigate just getting new knobs somewhere. Although it might be niuce to have an entirely new mortise lock. $25 isn’t so bad a price.

I’m a little embarrassed.

I returned the lockset I had originally purchased before I found out about the mortise lockset. And I asked a guy there if they sold mortise locksets. He said yes, and showed me where they were. I also got a new set of knobs, since really, it’s the knobs that were the problem, not the lockset.

Well, as I stood waiting to pay for my purchase, I examined the new lockset. It was facing the wrong way. My door swings the other way (in a nice way, I mean), and the latch would not work on my door.

I returned to whence I had come and searched for a lock that would work. They didn’t stock them. Then it occurred to me that the problem was with the knobs, and I had a new set in my hand already.

So I bought just the knobs, when home, installed them on the old mortise lockset and bingo! My door is in perfect working order once again.

A lot of trouble and confusion over nothing.

But, if nothing else, this little escapade reinforced my faith in the Doper community. Everyone who contributed to this thread was very helpful and knowledgable. As has been said before, you guys are the best! Thanks.

Dave just for the record, the latch on the mortise lock is reversable if you have the patience to take it apart and put it all back together. Since you do not need it it is a moot point.

The lockset I am imaginging should be pretty straight forward to change function.

Glad you have things under control.


Believe it or not, that thought did occur to me, for one brief, insane moment. But taking the thing apart and putting it back together again looked like more trouble and strife than it was worth. And, FTR, I probably don’t have the patience to do it.

And, as you noted, it was a moot point, since the original problem had to do with the knobs, not the latch or lockset. We don’t even lock the door with that mechanism.

This was really a tempest in a teapot, home improvement-wise.