Wood-fired kilns, salt glazing give potters unique experience

Why would a crew of potters, families and friends work into the night throwing wood into a kiln for 10 to 13 hours? These potters own conventional kilns, which use gas, electricity or oil and have automatic temperature controls.

However, some of us who like to imitate America’s early potters like the effects that only wood fires and salt glazing can produce. That’s what a crew will be doing here, Nov. 26-28 — Thanksgiving weekend — weather permitting.

I’ve fired with wood 20 times since we started in 1983 and plan to welcome the new century with this 21st firing. The kiln’s 25 cubic foot capacity will accommodate only about 45 pots. A few friends will bring their pots to this firing so we can experiment with various kinds of clay, new ways of stacking the ware in the firing chamber and the effects of a glaze made with wood ash.

Many early potters fired without shelves, stacking "raw" pots on pots, leveling and balancing the stacks using moist clay wads. We stack that way, too, but I prefer to prefire mine to a low temperature. It takes a steady hand and lots of patience to prevent breaking or chipping the dry raw ones. I once fired a kiln full "raw" just to prove I could do it, and it turned out fine. If wet or windy weather doesn’t interfere, we’ll be firing both raw and bisque fired pots this time.

Wyn, owner of W.A. Painter Pottery Works in Overland Park, Kan., has helped us fire five times. He will test-fire small commemorative jugs, which he stamps with customers’ personal messages. He fires hundreds of these wheel-thrown jugs in his electric kiln and has recently sculpted a few pigs, similar to the rare collectible ones made in Anna, Ill., long ago. He’ll test one or more of the pigs in the salt glazing.

Of course, we all sign and date our replicas to avoid misleading a customer.

Debra and Grieg Thompson, both potters, will bring pots to fire; they’re building a kiln near Harrisburg and will help with the hard work in this firing to get first hand experience.

Nikki Simmons from Russellville will bring raw pots and help stoke the fires though she has not even seen a wood firing. The rest of us have learned a lot by trial and error, but the learning never ceases and no two firings are the same. When the firing chamber’s temperature reaches 2,291 degrees, Nikki will take her a turn at scattering course stock salt over the fires.

We observe three firing cones through a peephole in the brick door. When the first temperature cone bends, we prepare to add salt. When the third cone bends, we put two pounds of salt in one end of a long angle iron, extend it into the very hot fire box and shake the salt out. Several saltings in each fire box requires a total of about 25 pounds of salt. The salt releases sodium vapor which combines with the silica of the clay to create the unique glaze.

To check the glaze buildup, we remove a loose door brick and "fish" out the first "draw ring." We drop the yellow-hot ring in water and examine its glaze. Several clay rigs are withdrawn, and when one shows the glaze buildup which we desire, we’ll stop salting but slowly stoke the fire boxes for a while more to allow the heat to penetrate evenly throughout the entire firing chamber. Then we close all of the kiln openings and retire for much needed rest.

If you’re interested in this process, drop by Friday when we’re stacking the kiln, Saturday when we’re stoking the fires or Sunday afternoon to view the results. However, no pots will be for sale. Of course, wet or windy weather will upset the schedule, so please call 442-2809 for instructions before driving the 10 miles to the farm.


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