Raku is a process where you take the work out of the kiln at top temperature (when the glaze is molten). Then most people take the work out of the kiln, they’ll then put the work into a trash can with combustible materials in it (newspaper, straw, etc). The combustibles ignite and then you put the lid on the can. This smothers the flame and the smoke and atmosphere inside the can makes interesting results on the work.
In the raku kiln at IUS, we usually use glazes such as: White Crackle, Steve’s Clear Crackle, Baylor Luster, Tomato Red, Copper Penny, Robin Egg Blue, Black Raku, Piepenburg Bronze, and others.
Example firing schedule for our raku kiln:
10:35am – light pilots
10:50am – burners on to 0.5, 220°
11:10am – burners to 1.5, 660°
11:40am – burners to 2.5, 1000°
12:25pm – burners to 3.5, 1400°
12:50pm – burners to 4.5, 1560°
1:20pm – burners to 5.5, 1750°
1:40pm – glazes molten, 1875°
One thing to consider is the decorative effect of leaving areas without glaze. Areas without glaze will turn black while in the trash can – here are a couple of examples of that by Liv Arnold.
In the Fall of 2022, the beginning students did a “Ritual / Raku project”. You can find a presentation of that project in the video below …