Search:

Tuf-Glide is mentioned often, and I have yet to try it.

Bicycle chain wax is great, penetrates, repels water, provides some lubrication, though generally not enough to need to tighten the pins.
...

Good advice here. I've had the same thing that Rolodave mentioned happen while polishing a knife, steel tarnished under running tap water. I've always wondered if for some reason the chlorine was a...