contact lubricant

On 16 Aug 2009 at 13:39, Mike Ford wrote: No--I've got a jar of Cool-Amp right here. It's a dry powder made up of (no trade secret) silver chloride, calcium carbonate (chalk) and sodium chloride (table salt). It works by laying down a *very* thin layer of silver over a more active metal (usually copper) by ion exchange (metallic silver is deposited out of solution in exchange for copper going into solution). The reaction stops essentially when a one-molecule thick layer of silver has been deposited. You can see the same phenomenon without shelling out $$$ for Cool-Amp by placing a clean nail in a solution of copper sulfate (blue vitriol). Copper will be deposited onto the surface of the nail. You apply Cool-Amp powder with a wet rag and rub until the silver appears. Since the layer is so thin, it will wear or tarnish away (via atmospheric sulfur) fairly quickly, so it must be replenished periodically. It's no substitute for real silver plating. No lubricants whatsoever--you wash any reside off before putting the object back into service. The stuff is fairly gritty, so I suspect there's a mild abrasive such as silica in the mix. I think that Cool-Amp may have changed their formulation over the years from silver-nitrate formula. --Chuck