layering of glazes, slips, stains, etc.
Posted 24 December 2012 - 05:04 PM
I know I can test and test and I'll have to do some of that. But, it would be nice to start out in the ballpark
Returning to pottery after 40 years absence
Posted 25 December 2012 - 10:43 AM
Posted 26 December 2012 - 08:09 AM
Slip is just a thinned out version of clay, so it needs to be bisque fired before it can be high fired (assuming you are bisqueing before glazing). It can be applied to wet, leatherhard, or dry pots. But in relation to your question, it will end up underneath any glaze. If you apply slip to an already-bisqued pot, then put the pot directly into a glaze firing, the slip is not going to fit, and will fall off in big flakes. I really enjoy brushing white slip onto leatherhard pots made of dark clay, then carving designs into the slip.
Oxides, stains, undeglazes, engobes are very flexible materials. They can be applied to green pots and bisque pots, under or over a glaze. Again this is generalizing, but most of the time I see potters applying these things to a bisqued pot, then adding glaze on top. This way, whatever design or effect you've created will stay where you put it. Though I've also seen someone make brushwork designs of underglaze on top of a glaze, the underglaze bled and shifted a little and the result was really pretty.
As for layering glazes on glazes ... my favorite way to approach this is to layer a matte or semi-matte glaze on top of a glossy glaze. This is most likely to create a "landslide" effect where the glaze runs down the pot when melted. Of course this should only be done on the insides of pots until you are very familiar with how your glazes will behave. Heck I am very familiar with my glazes, but I still only do this on the insides of pots. For me, when I see glazes that were moving in the kiln, I find that far more fascinating than colors.
Good Elephant Pottery
Posted 26 December 2012 - 11:45 AM
"But it does move," said Galileo under his breath.
Posted 27 December 2012 - 10:45 PM
And therein lie the risks of layering glazes on functional pottery.