I am wondering if anyone knows of a site or primer on repairing old style door knob assemblies. I have a 1929 house with mostly original glass or bronze door knobs and many of the assemblies no longer operate. Before we start taking them out, I wanted to review whats what with the insides and how one might fix them etc.


If anyone could provide any info I would appreciate it, thanks!

Views: 7503

Reply to This

Replies to This Discussion

These are not typically tricky things to work on. You remove the knobs and the box using only a screwdriver, and then you can open the box up with the same screwdriver. As soon as you lift the lid off, take a picture or two of the insides with a digital camera, so that there are no mysteries on putting it back together. Then you can look to see what is blocking the mechanism from working. (Paint on the latch, greasy dirt, etc.) Or maybe it just needs vigorous oiling.
phil is correct a good photo will save you lots of time,
all latches are not the same most are different each company liked there own design and parts.becarfull not to loose a flat spring springing loose when you open up the lock box.
Craig Phillips
B & C Emporium antiques and original hardware
I agree with everyone else. They are simple devices to just disassemble, clean & oil.

...as long as nothing is broken inside.
Ah that's the thing isn't it, I guess if anything IS broken inside you are out of luck at that point.
Not really.

Flat pieces could be brazed by somebody with the skills and a welding torch. They could also be reproduced out of flat stock with a drill-press, hacksaw & file.

Round pieces could be made on a lathe.

Springs can be reproduced using spring steel.

If you don't have the skills or equipment and paying a machine shop is out of budget, you could find original knob assemblies at local architectural salvage places, flea markets, or online.
Unless they were of a particularly bad design or very poorly made, I doubt that you will find them to be broken inside. Breaking a cast iron piece with the turn of a knob is pretty rare. My front door latch and lock is 115 years old, and I not only open and close it multiple times per day, but I also turn the deadbolt key 4 or more times each day. I oiled it once 10 years ago, but it functions beautifully. My back door modern cylinder deadbolt lock requires a puff of graphite powder at least every 2 years to function well. So, hang on to the old stuff. Clean it, oil it occasionally and you will be far better off than people with modern stuff, which simply doesn't last.
I have had the same problem in the past when working on a home. My favorite thing to do is lay out all the latches on a table. One by one I take each one apart and clean them, figure out what the problems are with each one, fix the ones I can, spray each one with a generous amount of graphite and put them back together. Decide which ones work the best and install them where they are used the most. Then I work my way down to the ones that don't work and can't be fixed and install them last. A lot of parts from one can be used in the others. You can also buy springs or spring steel at most Ace hardware stores. I have several doors in my house, mostly closet, where the latches do not work at all but I just shim the hinges to where the door stays closet when not latched. I have also ordered new ones from VanDykes, hardware section, on line. Hope that helps you out.

I am a locksmith by trade and I repair/rebuild antique mortise locks all the time.  If you don't know what you are looking at, or are not super mechanically inclined, you may find it difficult to repair a mortise lock.  There are so many different things that could be ailing it that I could not mention all of them here.  I have seen hundreds of broken cast iron parts inside of mortise locks, as well as worn-beyond-belief brass or bronze parts.  Broken or missing springs tend to be a fairly straightforward fix, but sometimes exactly how the original springs were set in place can be a bit of a mystery, or at least a challenge.  When you open up the case, you can never be sure that what you are looking at is how the parts were supposed to go together.  I have opened up countless locks and found that someone had improperly reconfigured the parts, and sometimes that's all that was wrong in the 1st place.  Additionally, you may find parts entirely missing, if a previous owner decided to remove them, or lost them.

Now, for your house, directly.  Hardware from 1929 could be a real challenge.  A lot of the lock manufacturers by that time had switched to steel mortise bodies and steel internal parts.  When you take apart one of these cases, parts can literally go flying, so watch your eyes!  I have had a close call or two with an errant spring hitting me in the face.  When these locks need service, repairing them can be almost impossible, unless you have donor parts.  I keep in stock hundreds of derelict mortise locks for just this reason.  If I can't repair the part, I can look through my locks to see if I have an identical one for parts (or sometimes complete replacement).

I strongly reccomend you veer away from the new reproduction locks that are on the market.  These locks absolutely define the meaning of CHEAP JUNK.  Your very best bet is finding genuine locks for replacements or parts.  Find a trustworthy locksmith in your area who has been around a while and is used to working on old locks.  He will have the expertise to repair your locks, and probably inexpensively.

Beyond all this, the most common problems I see with antique mortise locks are 1) broken springs, and 2) paint buildup.  Also, make sure your locks are well lubricated.  Use something light, like WD-40.  Graphite is ok, but hard to get where you want it, and is very messy.  It also never goes away.  I have repaired mortise locks where the only thing wrong with them was that there was too much graphite buildup!  Also, make sure your strike plate is still properly aligned to catch the latch (and the bolt, if you wish to lock it).  This can change from year-to-year, or even season-to-season.  If it's far off, remove it and reposition it.  If it only needs to be adjusted a little, use a metal milling bit that you can chuck into a Dremel or a drill.  Or, you can remove the strike plate and hand file it.

Andy wrote:   "When you open up the case, you can never be sure that what you are looking at is how the parts were supposed to go together."


That's true but chances are that the homeowner would have access to another assembly from a working door that he can inspect as a proper reference point.


I have been thinking of jumping on all the doors inside the house that do not shut or the knobs do not work. I have a couple that do work, except for the lock part, but that is not really needed.

They have what appears to me spring steel springs, basically a double twist around a post. 

I have not checked a machine shop locally, but are there places via the web that could duplicate the springs, if I could send them, do they exist?



Get Connected:

Follow Us on Twitter We're on Facebook!



© 2018   Created by Community Host.   Powered by

Old Houses | Restoration Products  |  Report an Issue  |  Terms of Service