|Detail of a large pot that I unloaded from the kiln today.|
|The "large pot" is about 23 inches tall (584mm), the one almost hidden behind it is 28.5 inches (724mm).|
|A big, heavy pot that was one reason I rebuilt the inside of my kiln... to take the height and weight!|
It really has been a busy time here, however sales of work are infrequent and that is worrying, very few people stop to look at the gallery. I am not altogether sure how to solve that one, or if there is a solution. Or if the solution is something that I could be happy with, but I keep working hard and trying to improve what I do, and there never seem to be enough hours in the day.
It has been delightful receiving Emails from some of the people who read this blog. People write wanting help with glazes, and it is very nice for me to feel useful in this way.
I made some cone 3 alkaline copper glazes. I am rather pleased with these as I developed them myself and did not adapt someone else's glazes. The Insight glaze software that I purchased recently was a helpful tool in this process. I worked out about a dozen or so glaze formulas, then tested the 8 most promising looking ones. It was most exciting opening the kiln and finding that the glazes had all matured, non had run off the pots, and they were a good colour. All of them used the same amount of copper carbonate (3 percent), and the different glaze bases gave me subtle variations in colour, which the camera did not pick up very well in the photograph unfortunately. I tested these on white earthenware, red earthenware that was dry, but not bisqued, and bisque fired red earthenware. It was most instructive seeing the influence of the clay on the glaze colour and glaze surface.
I have been giving serious thought about how to best direct the hot stuff from the firebox of my wood fired kiln through the chamber where the pots are. Since moving to an external firebox, I have been experimenting with cross flow and down draft configurations, which have worked to some degree, but I was convinced that temperatures in the chamber could be made more even, and the space be used more effectively.
When I am thinking about such things, I find that it is really helpful to draw simple plans on the computer. You don't need a complicated programme for this. In the past I used Open Office Draw, that was part of the Open Office open source programme, I now use Inkscape. My operating system is Linux, but I think Inkscape is available for Windows and Mac. Really all you need to do is to make some rectangles that are the same proportions as fire bricks, and some rectangles that represent your kiln shelves, and then make a big rectangle to represent the internal size of your kiln's chamber. After that it is a question copying and pasting some of your bricks and shelves, and pushing them around on the screen. I colour code my bricks and shelves to make the little diagrams clear enough for me to understand!
|When I am thinking of making changes to the kiln, I often draw bricks and kiln shelves to scale on the computer, and move them around.|
|After playing on the computer, there is nothing like heaving real bricks around. Here I decided on a new system of directing the heat around the chamber of the kiln.|
|I put kiln shelves on top to form the floor of the chamber, but I became dissatisfied with some aspects of the design.|
|So I changed my mind, and opted for a far more daring approach, bringing in the heat on the diagonal. |
|And here it is with the chamber floor in place.|
|Then the pots are loaded.|
|After the firing.|
We fired the wood fired kiln on Tuesday this week. I lit the fire at 4.10 in the morning, and stoked for the last time at 4 in the afternoon. Laura was a big help in firing the kiln, and did many hours of the firing and really enjoyed it. The cats kept us entertained throughout the day, they enjoy it when we work outside. I was so pleased that I had opted for my more "daring" arrangement of bringing the heat into the chamber on the diagonal, as the kiln really fired well. The kiln did not stall, and was easy to control and fire accurately. The flame flowed in a lazy spiral around the chamber, it was very beautiful to watch, and the chamber temperatures appeared to even out more and more as the temperature got higher. I think this was partly due to the chamber and pots becoming incandescent and radiating heat around the chamber.
This kiln has come a long way since it was built. The current fire box has a simple step grate and needs no raking in the course of the firing, and the ash from a 12 hour firing would fit in a 3 litre container. I really like the firebox, it is so much better than previous ones with conventional grates.
We had the pleasure of a visit from our friends, Robert and Shona, who live in the UK. Robert was Best Man when I married Laura, and we have all kept in touch for over 30 years.
|And here is Shona, Robert's lovely wife... and the ears of Nigella Stopit just visible in front of her!|
|Some jugs (or pitchers) from the previous wood firing.|
|Two 14 inch jars for a Karate expert! |
The "karate" jars were one of the more unusual commissions that I had in the last little while. The jars had to be made very strongly, as they are destined to be filled with sand and picked up by the rims. Picking up sand filled jars, using only fingers and thumbs, is a way that exponents of karate strengthen their hands! I had to put a tiger on each jar as the person that has them was born in the year of the tiger! I found it quite a challenge to make them. When freshly made they were a shade over 15 inches tall, and used about 7 kilogrammes of clay each. It made a refreshing change to have to make something heavy. No matter how light you make a jug or a teapot, someone will always complain that it weighs too much!