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Posted 4 Apr 2013Can someone with a Brent wheel please tell me what size the main bolt on the foot pedal is- the one that the two pieces of the pedal pivot on? I've been dealing with Brent for three days now to try and get some replacement bushings (the ones the bolt goes through on either side of the pedal) for a customer, and still no luck. I'm going to see what I can find at the hardware store...
Posted 19 Oct 2012There's been a little bit of discussion lately about raku kilns, so I thought I'd contribute with some photos of my kiln. I built this kiln about 6 years with the intent of making the safest raku kiln I could, as well as making it very easy to use. Since I run my own business where I teach a lot of classes, it is very important that I limit my liability and make sure the process is easy and fun. The kiln is built completely of soft brick, with an Alpine-type power burner coming up through the floor. There are several benefits to this design:
1. It's safer. Unlike the fiber-lined drum type kilns that require you to lift the entire body of the kiln off to access the pots, only the person actually pulling the pots from the kiln is exposed to the intense heat.
2. It's safer. There are no fibers to breathe in like the fiber-lined drum type kiln.
3. The pots stay hot. We have put up to a dozen pieces in the kiln at one time, and because we can keep the door closed between pulls, the last pot is still very hot and takes reduction very well. If we need to, we can even keep the burner running very low to keep the heat up while pulling.
4. The bricks hold a lot of heat. It gets to 800 degrees without turning on the burner, which means less fuel needed.
After the first firing, which takes 30-40 minutes, we let the kiln cool to about 500 degrees. Then we place small pieces of soft brick into the kiln, on which the pots sit. Putting the pots directly onto the hot shelf would cause cracking. By getting creative with the posting heights we can get a lot of pots in the kiln. We let them sit for about 2 minutes to warm up a little, then close the door. With the door closed and the bricks radiating heat, the temperature climbs up to about 800 degrees in a couple of minutes. When the temperature stops climbing we light up the burner and take it up to 1850F degrees, which takes 15-20 minutes. Then one person works the door while another person pulls the pots. Once the kiln is empty, we let it cool down again, remove the hot brick pieces and start all over.
For horse hair raku, the pots are only heated to 1250F degrees, which takes about 3 minutes. After pulling them from the kiln and applying the horse hair, we cover them with a can to slow down the cooling, since we usually use a smooth white body that doesn't handle the fast cooling all that well. During last weekend's workshop we fired about 20 horse hair pieces with no cracks!