Brass Corrosion 1

[brasscar]

We have a 1913 brass car with lots of brass, horns, lights, radiator, windshild, etc. The brass is not coated. We have been polishing it for years with various types of brass polish. They all work, some better than others. We recently tried a new brass polish. We are in big trouble!! Now all of our brass tarnished in about 48 hours. This is not your ordinary tarnish which comes on slowly over days and months. All of our brass turns the color of copper with a green haze over it. It also becomes very rough to the touch. We can repolish it with one of our old polishes. It will polish just fine and look beautiful and then almost immediatly start to turn bad again. What should we do? Help, help!!!

 

[AdhesiveGuy]

Brasscar,

Sounds like the new brass polish that you tried etched the surface of the brass increasing the susceptibility of oxidation. If you are looking for a coating to protect the finish, I would recommend that the brass components be conformally coated immediately after polishing. The very best coatings would be the vapor deposited type but they are expensive. If conformal coatings are not an option, you may want to have your parts checked by a lab for residual acid or other oxidizer left behind by the "new" polish. If an oxidizer exists and you can identify it, you could then attempt to chemically neutralize it.

 

[brasscar]

Could you recommend a good lab to check out our brass or tell us how to locate a good lab?

Thank you for taking the time to help us. Your post was most helpful.