Transcription
[Music] hi I'm Danielle the clay lady welcome to my studio on the clay ladies campus in Nashville Tennessee. today's lesson is going to be glazing 101.
glaze is basically five different components. you have silica, which is the glassy part of the glaze. you have clay, that makes it want to stick to a clay pot. you have a flux, that makes those things like each other and hold together. there's a colorant, either a natural colorant like red iron oxide that's just found naturally in the ground or a manufactured colorant, and water.
when you glaze what happens is your pot that's been bisf fired. the reason why it's called bisf fired because it's made your pot hard as a biscuit. usually that temperature is in measured in cone 06 to 04, basically around 1900 degrees. what happens at 1900 degrees is clays made out of alumina and silica and a flux, and when it goes to that low temperature, the silica melts just enough to make the pot hard and make the the particles stick together. but if you looked at a bisque pot on a microscopic level, it would look like a dry sponge.
so when you dip a pot into glaze, the water soaks into the pot and the glaze forms a crust on the outside. this is important for you to understand because if you have your pot water soaked, let's say you glazed it, didn't turn out right, you rinsed it, you tried to glaze it, it's not it's not going to work because your pots already water soaked. if you double dip your glaze, dip it in one color, then dip it in another, the second coating is not going to dry as quickly because again, your pot is already water soaked. for the same reason, this is why a pot that's already been glazed cannot be reglazed because there's nowhere for the water to go. it just runs off, pulling the glaze off with it.
so we have waxed the bottom of our pot. the reason why we wax is so that the water won't soak into the bottom of the pot, leaving a crust of glaze. if that crust of glaze is on the bottom of the pot when it goes into the kiln, it will actually fuse to the kiln shelf. so we wax the bottom. we use a cold wax in our studio, and I put the wax on with a small makeup sponge. they're inexpensive, and the main reason why I like is because when you dip it in the wax, you can go around that corner just right and pull that pot around. you'll get a nice even line.
while we wait for the wax to dry, we're going to stir our glaze up. in my studio, we use dipping glazes. glazes can go on brushing, dipping, pouring, spraying. we use the large 5 gallon buckets for all of our glazes. opulence glaze also comes brushable, as do other manufacturers. there's some advantages to brushing. you don't have to buy a full 5 gallon bucket of glaze. it's good just for testing or if you have a small home studio. we've just started using brushable glazes in the studio for maybe some detail work or some smaller pieces. but I'm going to stir this glaze up. as glaze settles, there's water on the top, the glaze falls to the bottom. we want to make sure that we get all the material up. a good vigorous stirring is important.
once we get that stirred up, it's time to dip the pot. I like to use dipping tongs just because it's manageable. it doesn't touch as much of your pot as if you use your hands. you can put your fingers on the wax part and your finger on the lip of the bowl, but most of my students use dipping tongs. we want to make sure that we get a good grip, but we of course don't want to push too hard. we don't want to pop through the pot. when you go into the glaze, I call it a one two three dive. one, two, in, three, out. one, two, in, three, out. hold it upside down. it's good to have a sponge in hand so that you can get that extra glaze off the wax part. we want to wait for it to dry. you can see how the water's soaking into the pot, leaving a crust of glaze on the outside.
after it has it chance to dry, I could dip it in another color. I could keep it on the same dipping tongs and go to a different color, or on this one, I think I might just want to do the rim. now, wherever there's a drip, we can smear that down. where the dipping tongs were, I'm going to use my fingernail and smooth that out just a little bit. we want to make sure that the glaze is all one level. I'm going to move over here to a white glaze to put a white rim on this pot. I'm going to stir this up, waiting for the glaze to settle so I can get a good even line. dip in, pull out. as I mentioned before, the second dip takes a little bit longer to dry because the first coating of glaze water soaked the pot. if I flip it over right side up too quickly, this extra glaze will drip down the side. you can encourage some of that to come off before you put it into the kiln. you want to make sure you get a good clean wipe on the bottom. any bubbles or any lines that you've seen, you can just gently tap out, and then you would fire that in the kiln.
so if your piece is too awkward to use dipping tongs, the protocol is to glaze the inside, glaze the outside, and then dip the rim. glazing this way is extremely helpful if your glaze bucket's running low or if your piece is almost larger than the bucket.
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