Bedroom lock fails to fail safe
Thanks to reader Peter S for sharing this with Made By Monkeys, an unfortunate story of failing lock mechanisms… He writes:
Last night I was trapped outside my bedroom because the latch inside the door disintegrated leaving the spring-loaded bolt engaged. So instead of going to bed, I had to get a ladder out and climb in through an upstairs window.
Armed with a screwdriver and a pen knife, I eventually managed to push the bolt back against the spring with only a little damage to the frame – much less than would have happened if I have shouldered the door from the landing.
It turned out that the lock mechanism had fallen apart inside the door in such a way that the cam could no longer push the bolt back far enough to disengage it.
If this had been a one-off, I would not be quite so miffed.
But the same thing happened to the same door three years ago and I deliberately bought this lock to avoid last time’s failure mechanism.
The earlier lock was largely made from cast parts and the bolt operating channel, which operates in tension, cracked across allowing the spring to shove the bolt uncontrollably into the frame.
That time I had just left the room without a stitch on and my wife who was trapped in side had to throw clothes out of the window so, after a daring dash onto the front lawn, I could dress and fetch the ladder and tools without being arrested.
I bought a replacement lock with a folded sheet metal operating channel which I knew would not crack, and it didn’t.
Instead the outer shell dropped apart with the same result.
Does anyone make a reliable door catch, or at least one that fails in a way that doesn’t need a ladder to fix it?
Indeed, can any other readers supply further examples of non fail-safe mechanisms?