This is what we find works best to keep your lock in its best working condition lubricate the lock cylinder. Do not use WD-40, WD-40 is a solvent, not a lubricant and will, in fact, remove any type of lubricant that is in the cylinder. Use a lubricant that has a silicone, graphite or Teflon base only. Make sure the lock cylinder is facing up and spray or pour the lubricant into the cylinder. Let it sit for 5 minutes. Place a rag on your workstation and turn the lock over onto the rag for a minute or so. This should be done several times a year to keep your lock working properly.