2 questions, #1 about Spray A #2 problems with kiln shelf

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Linda Hassur
Posts: 44
Joined: Sat Mar 15, 2003 10:40 pm

2 questions, #1 about Spray A #2 problems with kiln shelf

Post by Linda Hassur »

#1 I was working with BE 0137 French Vanilla and used Spray A on it. It turned a ugly yellow color. I know that this particular glass causes problems with interactions to other glasses. I'm assuming that this is the reason I had the problem.

#2 I have a kiln shelf that has one area that won't accept kiln wash. I also have a slumper mold with the same problem. I've used sandpaper and some other methods of trying to "scuff" up the surface but these areas are "slick" and won't accept the kiln wash. I don't have a sand blaster but is there any other thing I can try? Thanks Linda
Bob
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Joined: Mon Mar 10, 2003 1:01 pm
Location: Salt Spring Island, British Columbia
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Post by Bob »

Hi Linda,

The Lead in the overglaze reacts with something (sulphur?) in the French Vanilla to create the muddy colour .... at least that is what I believe the reaction to be. Someone please correct me if I'm wrong. Nonetheless it is a chemical reaction of some sort.

I think the only cure for the impermeable shelves/moulds is probably sandblasting. Go to a body shop, or find a place through the yellow pages that will rent you time on a sandblaster.

Hope this helps.

Cheers,

Bob
Barbara Muth
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Joined: Sun Mar 09, 2003 8:10 pm
Location: Washington DC Metropolitan Area
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Post by Barbara Muth »

Bob wrote:
The Lead in the overglaze reacts with something (sulphur?) in the French Vanilla to create the muddy colour .... at least that is what I believe the reaction to be. Someone please correct me if I'm wrong. Nonetheless it is a chemical reaction of some sort.

Bob
ding ding ding. I think you nailed that one right on the head Bob.

Incidentally, French Vanilla is not the only glass with sulphur, there are other glasses with similar reactions to those of French Vanilla. Ah the joy of color reactions.....

Barbara
Barbara
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