On 2/1/2006 at 3:27 PM Sridhar Ayengar wrote:
Does one need to use a strong acid for this cleaning?
Can one use a
concentrated weak acid instead?
I'd much rather use a dilute strong acid (such as hydrochloric or
phosphoric) than a concentrated weak acid, such as acetic. A chem flush of
a brass instrument typically uses hydrchloric diluted about 50:1. Gets the
calcium deposits and dissolves the oxide but doesn't etch the metal too
much. I've tried cleaning with acetic acid, but it's much slower.
As mentioned, sulfamic is another candidate--found in stuff like CLR
(calcium lime rust) remover and Tarn-X silver cleaner (along with
thiourea)--and may be worth a try if you're looking for a supermarket
solution.
Cheers,
Chuck