When the surface of old, used Glide Bar clamps become dirty, how would you clean them? I just came back from using Steel wool with Rubbing alcohol to clean the Clamp. I first used the Wool and grinded the whole outer surface part to make it shinier than before. After, i poured and rubbed the alcohol on the surface and wiped off the excess iron dust. Is this the correct method of cleaning? The clamps do look really shiny on the other-hand... This question falls into all general iron based clamps by the way.