[MF3D.FORUM:433] Re: Brass Tarnish

[Sam <3dhacker@xxxxxxxxxxxxx>]

I'll clarify my intentions. I made new pieces from brass stock, which stick
out like a sore thumb next to the remaining original parts. The original
pieces were shellaced, but through time some of the shellac has come off in
places and oxidized, leaving dark marks or blotches on the brass.

I'm not trying to fool anyone into thinking this is indeed 100% original.
This is my own camera and it is my desire to make it look as athentic as
possible or there's no point restoring it.

My experiments with ammonia turned the brass reddish brown instead of the
desired olive brown or black. The liver of Sulphur didn't do much at all,
both with bare polished brass and brass with scratched shellac. I'll try a
higher concentration tonight.



>I didn't catch what you are trying to tarnish, but often new items are
>coated with a varnish to keep them from tarnishing. I have used Masters
>Magic Antiquing Solution with goog results. We ordered this through an
>antique supply catalog. The bottle mentions that if the item doesn't
>tarnish, the finish needs to be stripped off. The product is some sort
>of acid and must be shipped in a DOT container.
>Rod


  >The liver of sulphur solution won't affect the shellaced or varnished
>areas. I had assumed you were going to oxidise some new brass
>parts to match existing ones.Normally, I'd remove the old finish
>via lacquer thinner and/or heat ,clean the metal in an acid bath,
>then dunk into the oxidant. Then clean well in water, if you want
>to lighten the new finish a bit,rub with fine steel wool, clear auto
>lacquer in a spray can is a pretty good finish.
>