Euro-lock with a slipped cam

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A frequent fault with Euro-style cylinder locks is for the central cam to slip and rotate through 180°, so that instead of protruding slightly from the body of the cylinder it sticks out at the top. This often makes it impossible to remove the key, either when the door is locked or when it is unlocked. This can happen if, by accident, keys are inserted from both sides of the lock at the same time, especially if the lock or the keys are worn. If the lock is worn, the problem is likely to recur, but it is not difficult to fix it, at least temporarily, by sacrificing a spare key.

The lock cylinder has a clutch in the middle that, if pushed by a key from either side, engages so that turning the barrel on that side also turns the cam.

  1. File down the point of a spare key until it is short enough to allow the barrel to turn without pushing the clutch. Don't file it so much that it no longer lifts the last pin.
  2. Insert a normal key into side A so as to set the clutch.
  3. Remove the normal key and insert the filed key into side A.
  4. Turn the filed key through 180°, taking the cam with it, so that the cam returns to its proper resting place.
  5. Insert a normal key fully into side B of the lock so as to push the clutch the other way.
  6. It should now be possible to rotate the filed key in side A by 180° again, without moving the cam, and remove it.
  7. Remove the key from side B of the lock.