Wednesday, February 15, 2012

Mortise Lock Repair 101

Now the the big renovation is complete, I've been able to find some time to get to the finer details of owning a 92 year old home. A few weeks ago we installed a rice paper window film to the bathroom door off our kitchen. The previous owners had used a curtain to provide the necessary privacy but we wanted something a bit more modern. It looks great! One problem: the heavy solid wood and glass door naturally hangs about halfway open. Since it took about an hour of shimming, adjusting, and cursing to get the door to close at all, I wasn't about to try anything fancy. Another problem: the latch on the door was not working and I haven't yet been able to find the correct Corbin key for the mortise lock. If you haven't seen an antique mortise lock up close, see below. They are truly amazing little gadgets:

They just don't make stuff like this anymore. The lock that I am holding is close to 5 lbs. of probably brass. But something is missing... Can you find it?

The spring, which causes the latch to rebound after the door knob is released had broken. In the picture, you can see most of the spring attached to the stationary peg while a small part is still attached to the hook and lever controlling the  lock. Where could I find a replacement? Lowes had a few springs, the smallest of which was the correct diameter but more than twice the needed length.

The picture is fuzzy, but what you're looking at is the spring from Lowes, snipped in half and re-bent on the end to make a loop.

I slid the mortise lock back into the door, re-installed the door knobs and face plates, and...

Voila! The Bathroom door stays shut! You can see the privacy film clearly in this picture, although not really the rice paper pattern.


  1. You should be so proud!!


  2. Thank you, Thank you, Thank you for posting this. Exactly what was wrong with one of the doors in our condo. And, nobody has the exact replacement spring on a Sunday. Very helpful.

  3. Been searching online for a half hour for replacement springs or a DIY. I was about to call it a night, and just head down to a lock smith to see if they had any laying around, or to buy a spring and try to work with it. Glad to see this worked for you, I have 2 springs to replace. Thanks!

  4. omg! i'm so glad i found this blog. i've been trying to figure out how to fix my bathroom door as well...for the very same reason. thanks!

  5. nice blog dear thanks for sharing
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  6. by all means.. your post is great!..I have the same broken spring on my bath old Corbin Mortise lock and was looking for a replacement spring, your solution is very good, but I wonder how were you able to cut and then bend that tempered spring wire and thus make and End loop on a brittle wire?

  7. That certainly saved you the expense for a new mortise lock. It’s wise of you to wrap up your home renovation by embarking upon these minor repairs. I hope you didn’t miss any details of your then 92-year old home. Anyways, thanks for sharing this trick!

    Helene Raymond @ Trade Squad

  8. Super helpful thanks. I needed to replace a spring as well and was on the Kilan site for a replacement and it hadn't even occurred to me to just get a new spring. Thank you! Was this size cut in half a good fit after some time using the door?