Pottery Workshop News
This page contains news of our activities in the pottery workshop. Information and pictures of what we do in order to produce our ceramics are displayed. In addition, we hope to explain some of the considerations required to make a successful ceramic item, that looks and feels good and, if functional, works well. Check back from time to time to see what's new, and scroll for latest news.
Firing at 1200°c part 1
Arthur has a gas kiln and electric kilns. For many years, he would fire in his gas kiln up to 1300°c with glazes he made himself from raw materials. He formulated a clay body with a blend of ball clay and molochite. This would become vitreous at this temperature, thus providing the properties necessary for stoneware pottery, which would be truly watertight and sturdy. This method of working served well for many years, firing bisque in electric kilns and glaze in a gas kiln.
However, two years ago, he was asked to start up a pottery class, whereby students would learn about pottery making, and this involved the management of large quantities of other people's pottery. It became apparent that it was not convenient or viable to gas fire so Arthur set about organising a range of new, convenient glazes which would appeal to his students. These would require firing at 1200°c, as opposed to 1300°c. He continued to use the clay body he made himself, which was perfectly fine for most purposes, but Arthur felt uneasy that the clay was not 100% vitreous at this temperature, which falls between earthenware and stoneware.
Arthur was surprised to encounter a difficulty in finding a manufacturer's clay with the right properties for glaze firing at 1200°c, so experimented with several samples of clays. This included a white earthenware with a recommended top temperature of 1160°c. Tests proved promising when he fired this clay to 1200°c. These tests involved small pots, and now Arthur is making a range of larger pieces to see how the clay performs at 1200°c.
To complement a clay body fired at 1200°c, Arthur has developed a transparent, white and 2 wood ash glazes to use with the range of favourites purchased for and by students. He has also discovered that a range of glazes from a prominent ceramics supplier, designed to flux between 1220°c and 1280°c, work just as well at 1200°c.
If the next firing of the experimental earthenware proves to be successful, all is poised to solve the initial problem of vitrification at 1200°C.
Arthur will post the results of the firing in due course, and meantime, he has displayed some pictures relevant to this project.