From the Kiln Room
We are now on our 40th firing. We are still waiting for the kiln repair to happen. I am more then impatient to get our kilns up and running at their optimal efficiency as soon as possible.
A few requests to help the kiln crew. There has been some frustration in identifying pieces and finding people’s shelves.
1} Please show your marks/signatures on your shelf. Put it on some paper and tape it to your shelf where we can see it.
2} Please remember to put your name or mark on your piece. We have provided underglaze by the weighing scales to do this. If unmarked they won’t be fired. Also, some people have four signatures/marks. It would help the kiln crew and simplify our job if you went to one mark only.
3} If you are working at the shed please request a shelf, so we have a place to put your fired pieces. If they are left on the shelf in the kiln room for over two months they will be discarded.
In recent newsletters, we have been talking about differences in types of clay; stoneware (high fire) midfire and earthenware as well as porcelain. Midfire is often called a stoneware but fires at a lower temperature. Midfire is designed to mimic stoneware/high fire. One main reason to use midfire is it fires at 20 degrees below stoneware and this can save 30% of firing costs. It is hard to believe that a 20 degree difference in temperature can make such a difference at over 1200 degrees.
Porcelain is hard to work with and has a tendency to warp and crack. Clay manufactures have included additives etc. which make it better to work with. Most clay is made from organic materials. Porcelain, on the other hand is made from a mixture of kaolin, silica, quartz, feldspar and a few other materials. Kaolin is a key component which gives porcelain its light structure and porosity. Porosity being the empty spaces within the clay which gives it it’s lightness. YES. I had to look porosity up. Compared to other forms of clay porcelain clay can be fired at high temperatures. So the clay body is firmer and has a higher hardness and durability. This allows it to be thinner and a have a more delicate translucent finish.
Linda, Gus, Jean, Katrina, Lynne, Douglas
And Catherine and Gabriel from the glaze room