Originally posted on February 12, 2009
This was my first blog and I have decided to repost it as a way of bridging old and new. It’s hard to believe that my old site was seven years old last month. I’m looking forward to our journey together in my shiny new web home.
Make Great Raku – Keep Your Eyebrows
A small number of Raku glazes can provide a stunning and ever-expanding palette. If you can control the reduction phase of the process, you can get wonderful and intimate crackle appearing beside eye-popping metallic lusters. But let’s face it; the best part of Raku is setting things on fire. So how do you get great results without singeing your eyebrows?
I have conducted and participated in numerous workshops throughout my career and have had the opportunity to see all sorts of reduction pit setups. Some artists use large metal cans, set upright, and place the pieces from the kiln into them prior to slamming the lid on. This is typically when the fun begins. Because the container is large you are tempted to try to put more than one piece into it. To do so, the lid must be opened. After three or four seconds the heat from the first piece in the can reignites any remaining combustible materials within and a fireball generally bursts from the can. This provides a wonderful opportunity for the unwary to lose their eyebrows, mustache, beard and any other beloved hairy surface on their head. Not only do you have a chance to look like Mr. Potato Head, but repeated opening and closing the reduction can causes the pieces inside to oxidize and nifty copper to fade away and turn green. So to some up, an upright can outright is bad.
So what is a potter/pyromaniac to do? I build shallow boxes for my pits and then fill them with sand. This way I can fire on any flat surface and do not have to dig up my precious grass/weeds. I place a small piece of broken kiln shelf (I produce more of this than I would like to admit) in a shallow depression in the sand and then sprinkle hardwood sawdust around the edges of the shelf shard. Now the pit is ready for the piece.
I have a nice collection of metal cans of various sizes that are inexpensive and provide consistent results. I try to find cans that barely fit over selected pieces. Make sure that the can will fit over your work before you pull your work from the kiln. There is nothing worse than holding a 1,600-degree hunk of clay and having no place to put it. I always test borderline sized or tall pieces before I put them in the kiln when they are cool. This eliminates flaming surprises.
When the glazes have melted and are free of defect, remove the piece from the kiln and place it on the kiln shelf pad in the reduction pit. Place the metal can over the piece and gently give it a little twist to bury the rim in the sand and develop an airtight seal. If you leave the can closed, the heat from the piece will consume all of the oxygen within the can and any metallic glaze will develop a bright luster. If you open he can briefly, the fire will reignite instantly, glazes will begin to oxidize and crackles will begin to form. The fun of the process is to play with the timing of exposure to create the most interesting and desirable effects.
Using this method, you have considerably more control over the outcome of each piece and at far less risk to your health and safety. The reduction process of Raku firing is not as random as you may have been led to believe. Yes, every piece is still unique and wonderful little surprises crop up every so often but that is why we continue to bear the heat and come home smelling like a house fire. Enjoy your firing this year and remember: an upside down can is the way to go.