RAY
GO TO A GUN SHOP AND LOOK AT BIRCHWOOD CASEY PRODUCTS.
DIFFERENT METAL REQUIRE DIFFERENT PRODUCTS.
EXCUSE MY CAPS, IT'S EASIER FOR ME TO READ.
CHUCK
I'll second the Birchwood Casey products. I use their brass blakener a lot. If you look at the boiler jackets of most of my locomotives, they're blackened brass as opposed to paint. I've used "Blacken-it", which is fairly commonly found in hobby shops, but I've not had nearly the results that I've had with the Birchwood Casey Brass Black.
As mentioned above, Birchwood Casey products are designed for different metals (aluminum, brass, steel, etc.) so you'll have to make sure you get the right stuff for the right metal. BTW, if you don't have a gun shop nearby, try Sulphur Springs Steam Models. They specialize in small scale live steam locos, parts, and other accessories.
Later,
K
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