26th January 2012
Bought a load of firebricks and built a very small sawdust kiln. I like the idea that you can do this with little effort once you have lugged the bricks. The sawdust was a mixture of shavings (both soft and hard wood) which was free and fine sawdust which I had to pay a couple of pounds for. I had some old slabs and corrugated iron for the top.
I first laid a layer of Financial Times on the ground and covered it with about 5 inches of the sawdust then laid bisque fired ware plus one greenware pot into this. One was upside down. Each pot had had a different treatment - one was covered in a salty wet piece of cotton, one was wrapped in steel wool, another coated in a solution of copper carbonate. One was filled with bracken and another with satsuma peelings - these last two made NO impression at all. Then one was glazed with shino and the last with transparent glaze. These two will be fired again in the electric kiln as they were rather matt and not very interesting.
I set it all alight with some kindling at 11.45am and let it just burn away - it is interesting that the fire burns downwards. There was a lot of smoke and I perhaps need to make the kiln more air-tight with a better fitting lid. When it was cool the next day (today) the FT was still pretty intact and the only sawdust not burnt was that in the upside down pot which thus preserved its colour. I have no idea how hot it all got and guess I need to get a pyrometer or use some cones.