Copper inclusions

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Courtney Branch
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Copper inclusions

Post by Courtney Branch »

I'm having difficulty getting copper and red colors from copper foil inclusions with float glass. I've have cleaned the foil with acetone, soap and water and sprayed both the foil and the inside faces of the glass with super spray or borax. I also have put the tin side to the outside and left at least a 1/4" glass border and I'm still getting mostly dark blues with ash gray highlites. Does anyone have a firing schedule that will encourage red/copper colors? Please any comments or suggestions which might bring about more copper colors and reds from copper foil inclusions.
Drewcilla
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Re: Copper inclusions

Post by Drewcilla »

Awhile back I searched for a solution to this issue and came across a recommendation to coat the copper with Clear glass paint to keep the copper color. Unique makes it; I don't know if others do as well. I've never tried it. If you do, please report back and let us know. Thanks.
john p
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Re: Copper inclusions

Post by john p »

I find that the thickness of the foil determines that,try 3 mill foil.
Brad Walker
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Re: Copper inclusions

Post by Brad Walker »

john p wrote:I find that the thickness of the foil determines that,try 3 mill foil.
John's right. The thicker the foil, the more likely it is to be purple/red. The thinner, the more likely to be blue.

Coating copper with Unique's clear glass color (or any decent flux) can keep it the original copper color, but you have to clean the copper well and apply thoroughly, best with an airbrush.
Lynn g
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Re: Copper inclusions

Post by Lynn g »

I bought some of the Unique clear color and was less than impressed. I got it at the Las Vegas show last year, and they recommended cleaning the copper well, coating it with lemon juice and then the clear, letting it dry and then firing. After I did all that, it was still dark. For me, it was a waste of time and $.
Lynn g
"Patriotism is not enough, I must have no hatred or bitterness towards anyone." - Dame Edith Cavell
Brad Walker
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Re: Copper inclusions

Post by Brad Walker »

Lynn g wrote:I bought some of the Unique clear color and was less than impressed. I got it at the Las Vegas show last year, and they recommended cleaning the copper well, coating it with lemon juice and then the clear, letting it dry and then firing. After I did all that, it was still dark. For me, it was a waste of time and $.
How did you apply the clear. The best way is with an airbrush. If you just brush it on, the results usually aren't that good. You need a good allover, even coat, and that's hard to achieve without an airbrush.

I've never used the lemon juice, so don't know what that adds to the equation.
Lynn g
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Re: Copper inclusions

Post by Lynn g »

Brushed it on. The lemon juice was per their instructions with no particular reason given, and frankly, I was so out of patience by the time I applied the clear that I wouldn't have wanted to dig out and set up my airbrush! I was doing this on wire, rather than sheet, so it was more hassle to get all sides coated.
Lynn g
"Patriotism is not enough, I must have no hatred or bitterness towards anyone." - Dame Edith Cavell
Stephen Richard
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Re: Copper inclusions

Post by Stephen Richard »

Lemon juice as we all know is a mild acid. So applying it to already cleaned copper will give a mild tarnish. Instead it needs a neutraliser.
Steve Richard
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