Changing Hands on an Old Skeleton Key Lock

Hello, friends! It's been a while, hasn't it?

Those of you following me on Facebook have been aware of the ongoing project to get the Makerspace up and running, including building a workshop and craft lab. In the process of cleaning out the old barn on the property, I discovered an old door that I believe my uncle had been working on a long time ago to put on the family home. It was, most likely, a hundred years old (just like any house you would find in this area), but the thing that set it apart for me was the fact that he had been hand-tooling it. The design was simple, but since I'm deeply rooted in woodworking, you can understand its appeal.

Today, I had the opportunity to hang the door. Now, quite a while ago, I removed all of the hardware in order to finish the door properly. That hardware, also exceptionally old, has been in a box all this time, waiting for today. Imagine my chagrin when I get the door reassembled and hung, only to find out that the mortise (the part of the lock set inside the door) was the wrong hand. I needed the door set as a Left-Hand, but the mortise was set up as a Left Hand Reverse (see illustration). What to do?

Step 1: Time to Grab a Screwdriver. . .

The lock I have is an old skeleton key-type mortise lock from the Reading Hardware Company of Reading Pennsylvania. This lock is easily from the first few decades of the Twentieth Century, if not older (I am not an expert on model identification).

Most of these locks are held together by one or two screws (this had only one, shown in the pic). It is always best when you work with hardware of this nature to work on a towel or tray, both to keep from losing small parts, and to save your work surface (in this case, the kitchen table). Remove this screw and set it aside.

Step 2: The Heart of the Matter. . .

Initially, the inner workings may seem a bit complicated if you're not used to digging into mechanical items, but careful examination will reveal the simple logic behind every part. This lock is rather easy to work with, compared with some others I've seen.

Now would be a good time to take a picture of the inner workings, just in case you have to take anything else out besides the latch. You DO have to put it back together correctly, right?

The part we need to concern ourselves with is the one circled in red.

There are two points of attachment on the latch; one connects the latch to the latch spring arm, the other to the spindle cam. Carefully remove the latch from the pin on the spindle cam (the other pin is attached to the latch itself, and just rides on the hooked end of the latch spring arm) and remove it from the case.

Step 3: A Closer Look at the Latch. . .

In this closeup, you can see the pin for the latch spring arm and the hole at the rear of the latch for the pin on the spindle cam. The part is quite dusty, but a soft-bristle brush will make quick work of that.

Step 4: And Replace the Latch. . .

Now we just place the latch back in the lock, after turning it around (note before and after pics). At this point, it is a good idea to evaluate the rest of the lock's workings. If everything works smoothly, you should be fine. If there appears to be a lot of dust and debris (spider nests, metal shavings, broken springs, etc.), you may want to prod a little further.

Springs are easy to find. If your local hardware store doesn't have the type for your lock, they can usually be found online. Metal shavings are indicative of excessive wear, and may also need to be replaced (again, found online at specialty dealers). If you feel the need to clean and lubricate, WD-40 is your best choice. Oil will make the lock work smoothly, but it will also collect dust and gunk, possibly fouling the inner workings. Oil also may leak from the mortise and soak into the wood of the door, either staining the wood if left natural, or causing any paint to release from that area.

Replace the cover and screw it back together. Remember not to tighten the screws too much, as it may cause the internal mechanism to bind and not work properly.

Step 5: And There We Have It. . .

There's your antique mortise lock, all ready to go back into your antique door. Assuming you didn't lose any screws in the process, you'll be back in business in a few minutes.

See you all again, soon!

--Bob W.