Oxidation

Oxidation is the deterioration of a metal when it reacts with oxygen and moisture in the air. On steel it shows up as reddish rust; on other metals, as white or greenish stains.

In locks and lock cylinders it starts on the inside, where you cannot see it. The first thing you notice is that the key goes in stiffly or is hard to turn. If nothing is done, the mechanism seizes up and one day the key will not turn or it snaps.

To slow it down, clean the face of the cylinder from time to time and use a dry lubricant or one made for locks, never cooking oil, which traps dust and sand. If the lock is already badly damaged, we look at it under security upgrades or as a repair.