4 DIY ways to repair a broken door lock

If you have a broken door lock, there a few methods you can use to repair it before you call a professional locksmith.

If you catch a door knob or lock problem early, it’s often possible to fix the problem before it gets to the point where the lock no longer works.

• Often, a malfunctioning latch assembly or lock mechanism is what’s at the root of the problem.

A poorly fitted door can cause an improperly functioning latch, or the lock mechanism may not work simply because the lock is dirty or dry.

• If this is the case, try lubricating it with graphite.
• Make sure to avoid using any kind of oil, because this will gum-up the works.
• If your door key is sticky, once you get the door open, try the key again.
• If it works easily, the deadbolt isn’t engaging the strike plate properly.
• If it doesn’t turn in the lock with any ease, try lubricating or cleaning the lock.
• Next, spray some graphite into the cylinder and try the key a few more times.

If the key turns but doesn’t unlock the lock, take the lock apart so that you can be sure the cam or tang is properly connected with the bolt.

• If you see any broken parts, replace them and reassemble the lock.
• If the key won’t go into the lock at all, check if the weather is cold enough for the lock to be frozen.
• If it is, try heating the key and inserting it gradually into the keyhole.
• Keep repeating this process until the ice has thawed.

If you’re using a new key that won’t go in or work properly, it may have rough spots that need to be filed off.

• One trick to find those spots is by holding the key over a flame to blacken it with soot, then insert it into the lock, turning it slightly, then pulling it out.
• File down any shiny areas where the soot was removed by the rough spots.

If none of these tips work, it might be worthwhile to call a professional locksmith and replace the lock entirely.