# Fixing Old Doorknob



## Just Bill (Dec 21, 2008)

That is a mortise lock, common in houses before, say, the 40's. They were pretty rugged and lasted for years. There are ways to replace them with modern locks(brass plates) without major surgery to the door. But often, people like to keep these old locks for the character they add to the house. While the locks all look alike from the outside, there were several different manufacturers and lots of different models. I am sometimes lucky, sometimes, at getting them to work, but parts are difficult to find. There are two local companies I rely on for parts and expertise. One is a local locksmith that knows of such things, the other is a used house material dealer that really knows those old locks. Check your yellow pages, there should be someone like that locally.


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## gregzoll (Dec 25, 2006)

There is a thread about the retro kit avail for modern locksets to fit into the old Mortise lockset. You can find suppliers online, but will need the measurements of the lock box before ordering. The drawings are also available online to show how to put them together. I have one in the basement on a door, but not able at this moment to take a pic of the inside.


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## Scuba_Dave (Jan 16, 2009)

Not sure on the spring placement
But at my last house I bought a new "old" lock that was similar to replace a defective lock
They do still sell these


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## Ron6519 (Mar 28, 2007)

Carefully take apart one of the locks that work properly to see the correct spring placement.
Ron


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## Maintenance 6 (Feb 26, 2008)

The coil spring was someone's attempt at a previous repair. It is not the original. There should be a large flat piece of springsteel that runs along the top of the case. It would hook above the lug that's cast into the case. It would have a slight hook bent in it. One end would hook towards the face plate, while the other would hook under the cast "L" shaped piece in the top right. That spring serves to extend the latch bolt and re-center the knobs. If you can get some flat spring steel from a locksmith or maybe a gun repair shop, you can fabricate a replacement. Put some light grease on all of the bearing surfaces when you re-assemble.


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## gregzoll (Dec 25, 2006)

*Inside of lockset*

I finally was able to get the one out of the spare door downstairs. Now of course, gives me a reason to fix the center threaded rod for the handle on the front door.


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## Maintenance 6 (Feb 26, 2008)

And of course this one is a different style. And of later manufacture than number one. The stamped steel parts are a give away.


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## gregzoll (Dec 25, 2006)

It is only out of home that is pre-1940. As for the OP, theirs is also stamped out of sheet stock, but the idea is there as to how the inner workings should appear.


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## Maintenance 6 (Feb 26, 2008)

gregzoll said:


> It is only out of home that is pre-1940. As for the OP, theirs is also stamped out of sheet stock, but the idea is there as to how the inner workings should appear.


Nope, different era, different mechanism. Op's lock is cast parts, and latchbolt sits well below the centerline of the knob hubs.


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## gregzoll (Dec 25, 2006)

The OP lockset is not cast, it is stamped, just like mine. You can tell if they are cast by 1) the parts would be thicker, and two, the ridge on the one piece would not be a clean impression that is the case of a stamped part. As for era, theirs may be a few years earlier, but same decade. Keep in mind, there where multiple manufacturers of those locksets, just like today, you have multiple manufacturers.

The picture I posted is only for example, so that the OP can get a idea how the inner workings are laid out, so they know how it should appear when not broke. Only way they can match info on theirs is by opening up a known good unit by taking off the cover carefully and comparing.


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## Maintenance 6 (Feb 26, 2008)

No, sorry. Not even in the same decade. Yours is probably 1920's-1930's. OP's is late 1800's. Cast latch bolt. No place for a coil spring. Uses a flat spring. Yours uses a wound spring to tension the knob return yoke and a separate spring for latchbolt return. I worked on way too many of these. Many made by Corbin, Reading Hardware, Penn, Russwin and a bunch of others. This is the last I post on this. I explained how to fix it. The coil spring doesn't belong.


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