Have a door that won’t latch anymore? Nothing happens when you turn the doorknob? Live in an older home with vintage glass or brass doorknobs? A broken door spring in your antique mortise lock is likely the culprit. Finding replacement springs can be a tricky. No worries, I’ll show you how you can fix a vintage door knob by using a common rubber band instead.
Remove the door handle
Start by removing the door’s handle. Find the small screw on the base of the spindle and loosen it without removing it. Unscrew the handle counter-clockwise until it comes free. Make sure you hold the knob on both sides as you do this. Slide the spindle from the door.
Remove the antique mortise lock from the door
Next remove both screws from the lock face (the metal plate on the inside edge of the door). Note: if you have a painted door, you may need to score the edges of the lock face. Insert a screwdriver into the hole from which you removed the spindle. Twist the screwdriver in order to pop the mortise lock free from the door. You should then be able to grab it and slide it out from the door freely.
Unscrew the cover
Gently remove the cover by removing the small screw. At this point I would advise you to take of picture of the interior mechanism just in case… that way if any parts get knocked out of place by accident you’ll be able to easily reassemble the lock.
Install rubber band
Starting from the latch, follow the path that leads up to a hook. That’s where you should find a broken or missing spring (top left corner in the picture shown). Remove the old spring and discard it. Find a thin and supple rubber band. You will need to reduce the size enough so that it will hold tightly on the hook and the pin shown here. Wrap the rubber band around your fingers until the desired length is reached.
Insert the rubber band onto the hook first, then holding it in place, push the other end down onto the pin. Note that the rubber band must hold in position without any assistance on your part. If it comes off, make the rubber band shorter.
Replace the cover and test the handle
Once you have it securely in place, gently re-position the cover and tighten the cover screw. Before reassembling the door, test the latch. Insert the spindle and turn the knob to see if the latch now retracts and springs back into position.
Reinstall the mortise lock and door handle
Follow the steps you took to remove the antique mortise lock and handle in reverse in order to reassemble the door.