posted April 21, 2000 10:01 PM
I am finishing up 5 military cast bronze plaques that are 15" in diameter with a lot of raised detail that will carry the polished highlights. I have used oxalic acid to turn the background black or charcoal color on other jobs. But, in this case, I want a brownish/bronze color. They will be sprayed with Sikens clear after all this buffing and polishing is done. Anyone ever achieve such a color? Bear in mind, this is not a PAINT, it is a chemical reaction to actually oxidize the metal. (don't shoot from the hip with a reply if you haven't actually tried it yourself) I have a background in chemistry but this particular bit escapes me.
------------------ John Smith Kings Bay Signs Kingsland, GA
Purveyor of fine signage and Innovator of good things yet to be
www.finewoodsigns.com
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Posts: 816 | From: Central Florida - The Sunshine State | Registered: Jan 2000
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posted April 21, 2000 11:58 PM
Well, You have hit me right in the nose on this one. I own and operate an art bronze foundry. You can use selenous acid for a dark brown bronze color, and if you want a more redish brown tone you can add heat and use ferrick nitrate. Actually, you can do a liver of sulfer base tone, which turns blackish gray, and then use the ferrick nitrate with about 400 degrees of heat to get the redish brown tones. It is a much more stable patina, and will not change too much over time. It may then be coated with incriliac (spelling?) for outdoors, or metal lacquer for indoors. and then possibly a wax. I can give you more specifics if you e-mail me........bronzeo
posted April 23, 2000 09:20 AM
Jack, thank you for your invaluable info!! I am now off to see the Wizard in search of selenous acid. I think I need about 10-12 ounces. Have you ever compared incriliac clear to an automotive UV clear such as imron or sikens ??? Just wondering which one would be the best for longterm protection that won't chip off with time. You do indeed have a beautiful and very informative website!! I firmly believe that the net is the way of the future for commerce. But, we still have to do as much local work as possible in our own neighborhoods. I too have toyed with the idea of a small billboard, but, I am still quite busy with the yellow pages and my website and that is enough for now. OH! like your bronze work, improperly applied primers and finishes on your signs, will yield less than satisfactory results !!!! The professionals here on the BB can share a 5 minute tip that can save you 5 days of heartache ! Good luck to you in your new medium and thank you for sharing your information of the bronze techniques. I do not take your info sharing lightly as I know you have gone through the school of hard knocks more than once, just as I have !!!! thanks again..... John
------------------ John Smith Kings Bay Signs Kingsland, GA
Purveyor of fine signage and Innovator of good things yet to be
www.finewoodsigns.com
WoodCarver on mIRC chat
Posts: 816 | From: Central Florida - The Sunshine State | Registered: Jan 2000
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posted April 23, 2000 10:16 AM
John, You can get the selenous acid at Rio Grande, a jewelry equiptment provider 1-800-545-6566. They call it black brown patina order number 335-119. You can spray with a spray bottle it but be very careful and cover you parts well and stay upwind. Rinse immediately and use fine steel wool to accent the highlights. Rinse very , very well and get rid of the steel fibers as well as the acid residue that will show up for the next few hours at least. You can post questions to the board at www.artmetal.com/brambush/index/html for other vatiations. This particular patina gives you a color of about the bronze anodized aluminum doors and windows. The ferrick nitrate, from a chemistry house (college lab or art department) will have liver of sulfer, and ferrick nitrate, to do the more redish versions. Actually I just use a good metal lacquer, but my work is for indoors display. The incriliac is all I have had recommended for the outdoors, and I don't know much about it. They do at the artmetal board. Cheers,Bronzeo thanks for the compliments....
------------------ Jack Davis 1410 Main St Joplin, MO 64801 www.imagemakerart.com bronzeo@prodigy.net http://www.imagemakerart.com
Posts: 1549 | From: Joplin, MO | Registered: Mar 2000
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