Matt, Jim's post caught my interest. On your site you said your porcelain best fired in a mold. My question is, does the porcelain slump any into the press mold. If so it would help cut down on warping. One other thingshould it be fired to cone 6 bisk then refired to a lower 06 to 04 glaze firing like bone china?
Thanks looking forward to testing on some jewelry
The glassy porcelain does slump into the mold so I decided to take advantage of that and do porcelain slumping. To make the plates I have been making flat discs setting them on top of the molds and firing to cone 6, the clay slumps into the mold and takes the shape of a plate with no warping like you mentioned. So the clay doesn't stick to the mold, I coat the bottom of the discs with a thin layer of normal porcelain and the mold with alumina, the bottom comes out looking like unglazed porcelain but luckily that's popular at the moment. This method seems to work best in shallow molds.
I could fire it like bone china but for now I'm trying to once fire or have a really low bisque, and just except that the bottom will look unglazed.
The recipes on my blog are pretty much a standard cone 6 porcelain, slumping isn't as much a problem with those. The recipes are sorely are out of date, I just threw them up there if someone wanted to mess around with them. The glassy porcelain recipe I haven't decided what to do with yet.