Posted by Wade on March 12, 2004 at 10:29:33:
In Reply to: What exactly is posted by chemical cleaning on March 12, 2004 at 03:51:24:
THIS IS "LORE" PASSED DOWN TO ME FROM ONE OF OUR OLDER TECHS AND IS ONE OF MANY PROCEDURES THAT USED TO BE USED. I am not claiming that this is what ALWAYS happened. This is a procedure used many years ago, more or less. All CURRENT methods are variations on this theme that use much safer chemicals. This is NOT what will happen to your horn if you get a chem clean today. There are a number of newer chemicals and procedures that are easier, safer, and much less nasty to use (thank goodness). But this procedure illustrates what happens and why quite well.
1. Wash Out: The horn is disassembled and scrubbed-out with strong, grease-cutting soap in a special (jumbo) sink.
2. Muriatic Acid: The horn and parts are run through an acid that eats off old, hardened deposits from the metal, leaving it clean and ready for the next acid.
3. Wash Out.
4. Bright Dip: Then everything is run through another acid to even out the appearance of the metal by removing surface corrosion and discoloration.
5. Wash Out.
6. Sodium Cyanide: Everything then soaks in a high pH base solution (NaCN) that neutralizes any acid that might not have been washed out. Bright dip keeps working after it dries (albeit slowly) and if not totally neutralized can eventually eat through the metal. This stuff is now very illegal as it is fatally poisonous.
This is one procedure that works GREAT but will bring the wrath of OSHA down upon thee! Nasty, nasty, stuff . . .
Lee and Joe would know how to explain this better than I.
Cheers!
Wade "if your shop cat falls into the bright dip tank over the weekend it will have fully dissolved by the time you return" Rackley