Opened the Bisc firing yesterday, I had made up a batch of green slip luckily I did a test pot. 100% Ball Clay 5% Copper Carbonate. The recipe said Copper Oxide, but I didn't have any so I used Copper Carbonate. any suggestions would be welcome.
Don't worry about the cone not bending, that was just a precautionary measure to stop me over firing.
7 comments:
Glaze them anyway and see. One of my slips just looks grey at bisque. Anything can happen, it usually does!
That's pretty much what my green slip looks like when it's bisqued. I mine has 6% copper carb in it (in a white slip base). The glaze will change it for sure.
I don't know the formula for substitution, but Carbonate doesn't have as much actual copper in it as oxide.
In stoneware it's usually between 3 and 5% - that's more than what you have not on top of it (If you see what I mean) but copper carbonate is a lot more stable so I'd go with carb not ox' if I were you.
I think it'll be fine, maybe a little pale, but fine. Cop Ox tends to be about twice as strong I think, I use 5% copp ox. A lot depends on the glaze that covers it too. Look foward to seeing finished pots.
she'll be right mate...starts out brown soon turns green......bung her in a glaze firing and at risk of mixing my cultural metaphors- bobs ya uncle!
OK It's in the glaze firing today.
Post a Comment