Friday, July 20, 2012

Broken Key in Lock

My wife, during yesterday's panic, broke the key off in the lock of our new telescope garage.  There isn't much if anything of the key in the lock to grab with pliers.  My thought is that because the key is a bit less than 1/16" width, I might solve the problem by buying a 0-80 tap, a .0469" drill bit, and a 0-80 screw.  I should be able to put just enough of a hole into the part of the key remaining in the lock to thread it, and then use the 0-80 screw to gently pull it from the lock. Any other suggestions?

UPDATE: My wife managed to (and I don't know how) get the doorknob out of the door without damaging anything.  Now I can take the lock into a locksmith, instead of the locksmith charging me a fortune to come up here.


  1. Yeah, a toothpick, and superglue.

    Or two.

    Or three.


    So long as you have enough bonded surface area, it WILL eventually have enough bonded strength to pull out, without the severe fiddliness of tapping a hole that small.

  2. Having done this before. Two suggestions. One usually the broken edge is not buried too deeply into the cylinder. I have used a dental pick [the one used to scrape your teeth] to extract the broken piece. No 2--- along the bottom of the lock e.g.-- entrance where the "teeth" of the key ride on insertion... there is some clearance for a dental pick to extract the broken key. Last resort-- carefully drill out the cylinder or call a locksmith!

  3. If you've gotten the doorknob off, you *may* be able to push the key out from the back of the cylinder. I'd at least take a look before taking it to the locksmith.

  4. Most (or at least many) lockpick sets include a broken key extractor. It's basically just a little tiny harpoon.

    If you haven't already taken the door knob in take a little bit of flat steel and make yourself one.

  5. As Dennis said dental picks are the first thing to try. There are specialty locksmith picks known as "key extractor picks" for this, but the mini dental picks will be easier for you to get if you don't already have some (can't imagine any person that likes to do any kind of mechanics not having those). Anyplace that sells tools usually has the dental picks. Harbor Freight has a decent low price selection.

    Two picks are easier to use if the cylinder is still in the knob and in the door so you'll probably want to put the knob in a vice and then use two picks to apply pressure to the key while pulling.

    The ultra fine tip tweezers might
    be another option. I'm pretty sure Harbor Freight also has those. Another thing everyone should have in their toolboxes! ;-)

    Let us know how it works out and good luck.

  6. I've used street cleaner brushes - small strips of steel that you find in the gutters after the street cleaner go through. They are usually honed to a fine edge on one end. Shove one one either side of the key you will only be able to get about a sixteen inch of contact. Then pinch them together with plies and pull.

    The dental pick works well also.

    My neighbor tried the toothpick and superglue and ended up gluing the key into the lock...

    As for your wife getting the knob out, I'm assuming she had access to the inside of the door, and a phillips screwdriver. If she didn't have access to the inside of the door, you need a better lock.

  7. My wife isn't sure how she removed the doorknob from the outside. I don't see how she did it without damaging it. Fortunately, this isn't on the living quarters. And there is a deadbolt as well (which wasn't locked).

  8. The door was closed and locked when she removed the knob? What manufacturer is this? I hope it isn't Kwikset, I have a lot of brand installed.

  9. It may be a Kwikset (she has it with her, on the way to the hardware store to have them try and remove the broken key). But I wouldn't worry too much. It took her a couple of hours. I doubt that there are many burglars with my wife's determination and intelligence out there.

  10. If you have access, it might be cheaper just to replace the lockset.

  11. That is quite a dilemma. I the toothpick trick will do to pull the key out, but maybe there's something inherently wrong with the way the lockset, since your wife was able to remove it from the outside. I have to agree with the other comments and suggest that you just go with replacing the lock, or at least taking it out for a while and have it checked by a locksmith. Anyway, I hope whatever you ended up doing was for the better!

    Joyce Roberson @ LockedOut LockSmiths