Paul's Raku "Recipe"
RAKU CLAY BODY
Any clay can be used if the non-plastic materials are increased, i.e. about 30% sand or grog.
|Soldner's raku body:|
|Lincoln fire clay (plastic)||50%|
|sand, all mesh||30|
The usual ceramic stains or metallic oxides used in pottery.
|other organic matter|
Pots with small openings are difficult to raku without breaking because the outside heats faster than the protected inside, creating tensions. Such pots can be more easily heated by placing them in a cold kiln and bringing them up to temperature while heating the kiln. Stoneware pots can be refired with raku glaze by this same technique.
Crazing may be induced by cooling the pots fast in the cold air or by blowing upon it. After returning the pot to the smoke vessel, smoke will penetrate the craze.
Refiring can be repeated many times.
Copper reds are achieved by building thin layers of copper oxide between layers of glaze, then smoking before the glaze becomes too molten, for a 5 to 10 second reduction.
Unglazed clay will turn black with prolonged smoking . . . 5 minutes or more.
Engobe can be made from any engobe formula plus the addition of equal parts of a basic raku glaze.