Post #224751 by Red on Mon, Apr 3, 2006 5:33 PM

Rum Demon, nice job on the mold.

The white pox marks on the inside of the mug are underfiring. I've had this happen a few times on molds where the piece was thick and I sent it out to get fired. If your shop is firing with a kiln tender, they tend to go under the correct temperature because the cone is closer to the heating elements and bends before the entire kiln has reached the proper temperature. Some people fire with an 07 cone if their goal is 06 because of this effect. If your shop has an electronic kiln, then maybe they're loading their kiln too full, or your pieces are near the center.

When working with stoneware (i.e., cone 6 versus lower-firing cone 06), you cannot stilt your pieces. You have to dry foot them. That means no glaze where they touch the kiln floor. If you've seen stoneware in restaurants or even at home, you will feel that the base is unglazed (feels rough). Any part of the bisque which is unglazed is unsafe for food, by the way, so your mugs with the pox are unuseable for food.

I am fascinated by what you've done so far. I've learned a lot about how the finishes look on the mugs by reading your thread and looking at the pics. Thanks for all of your great posts, they have helped me understand the ins and outs of what this is all about (being a first-timer it always helps).