Files should always be protected from grease, water, or nicks that can make them less effective. When carrying files in a toolbox, it is a good idea to wrap them in a cloth. When storing, try to hang them in a rack or keep them in a drawer with wooden divisions. Keep file teeth clean by using a file card or a wire brush to clear the grooves.
When installing a new or replacement lock, be sure the keyway is positioned so that the cuts of the key will be inserted upward. This will reduce the chance of dirt, dust, and water (which can turn to ice in cold weather) settling in the lock mechanism creating a lockout or stiff operation of the cylinder.