Raku
I led another raku workshop this last weekend – or was it the one before that? – that I thought I’d share with you guys.
Raku is an ancient Japanese technique in which red-hot ware is unloaded from the kiln and placed in metal bins filled with combustible materials. The lids are clapped on once the material begins to burn, and the smoke and reduction of oxygen brings all the heavy metals to the surface of the glaze – so you can get gorgeous bright colors with lots of crackling and iridescent or metallic flashes. It’s not food safe – even if you use a non-heavy-metal glaze, the kiln only gets up to cone 010 or so – but the pieces are still delightful to display. No two are ever alike.
Thanks to participant Judith R., I have pictures I can show you.
First the kiln is loaded with pre-warmed ware.
You have to wear leather gloves at this stage because the ware is probably 300 degrees. Not to mention the kiln – hot hot hot!
This type of kiln is called a clamshell. You can see why.
Once the kiln is closed, the firing process takes about 45 minutes and must be contiually monitored and adjusted. Towards the end, the kiln itself is reduced a bit, meaning you cut off its supply of oxygen. See the flames leaping out of the top and the side peeps?
You have to keep looking in from the outside, via the peeps, to gauge how far along the ware is and whether it’s just about time to open the kiln. It helps to wear polarized sunglasses.
Then the kiln is opened and everyone dives in with long tongs to get their glowing pieces out – and over to the burn bins – within those first few seconds!
The “kiln master” has to wear asbestos gloves, and everyone else must wear leather. Everyone knows in advance exactly where they’re going and in what order. Having a good “kiln dance choreographer”, like I did, is a huge boon. Because I’m sure you can appreciate how much of a bad idea it would be to have ten people weaving haphazardly around each other on the verge of panic, each with a piece of glowing pottery held out as far in front of their bodies as possible in a precarious pair of tongs.
Having gron up with California’s fire-safety-consciousness, I can say that the first few raku workshops I did were stress-fests for me.
The results are worth all the trouble, though. Too bad I didn’t get any really great pics of ware we did that day (the pic below is taken from www.artglass-pottery.com) but it gives you an idea of the results you can get.
