Ceramics: Clay -Raku + Tiles Sept 16+17

UNIT OVERVIEW

September 16-17

Material Science: We will begin by investigating the properties of ceramics. In class students will be working with clay to investigating the change in size and weight as the clay shrinks when fired. In our second lab students will create slip stoneware and soft clay stoneware. These will be tested along with greenware for thermal conductance and flexural strength.

Art Studio: We will be creating clay pots for raku firing. We will also create dimensional tiles that will proceed through the entire manufacturing process and all four major materials units -from proto-type to final cement tiles.

ART STUDIO ASSIGNMENTS

Assignment Part A - MONDAY SEPT 16+17

Take notes over the following materials about raku pottery.

https://thepotterywheel.com/what-is-raku-pottery/

What is Raku Pottery?

The Raku pottery tradition originated in Japan in the 16th century. In its original Japanese form raku pottery was typically hand-built and used to make tea bowls. These are small semi-porous drinking vessels used in a Japanese tea ceremony.

Over the years, the Raku pottery process has evolved. Raku pottery ware has developed from the humble tea bowl to any kind of pottery you can imagine.

Features of the Raku process:

Raku firing is a fast process. The kiln is heated up more quickly than a non-raku firing. And, the pottery is removed from the kiln when it is red hot. After being removed from the kiln it is cooled down quickly too.

Normally during pottery firing, the temperature changes in the kiln are managed carefully and happen gradually. This is a way of protecting the pottery from sudden temperature shifts.

Raku is a low fire process, reaching around 1830F (1000C) at its highest temperature (vs. the standard white clay we are using in ceramics bisque fires to 1945F). In raku, pottery is removed from the kiln when red hot. It is cooled rapidly, often in combustible material like sawdust or paper. Raku firing is usually done in a fuel-burning, rather than an electric kiln.

Sudden changes in temperature in the kiln can cause ‘thermal shock’ in the pottery. This refers to the stress that pottery undergoes during rapid temperature changes. It is thermal shock, amongst other things, that contributes to pottery cracking if it cools too quickly.

By contrast, in Raku, the pottery is removed at its highest temperature and deliberately cooled down quickly. It is because of this that pottery is more vulnerable to break or explode during the raku process. There is more collateral damage in a raku firing than a regular pottery firing.

Raku requires preparation before you take on this form of firing. First, you need to use a clay body that can withstand the thermal shocks it will go through. Second, you will need a kiln that is appropriate for the process. Third, you need to have the proper equipment.

Pots are removed from the kiln when they are molten hot and put into an enclosed container with a combustible material like straw, leaves, or paper. The closed (usually metal) container, combined with the burning material creates a reduction atmosphere.

Reduction is a firing term that refers to a lack of oxygen in the combustion process. This lack of oxygen in the atmosphere causes the fuel to search for oxygen elsewhere to allow for more complete combustion to take place. This can take place during a firing as in 'reduction stoneware.' In this conventional situation, the additional oxygen is found chemically bound in the the clay body and glazes. The result is characteristic reduction effects.

In a reduction atmosphere oxygen is being burned out of the air in the container. The flames then search for oxygen in the pottery and glaze. This creates a particular organic-rich appearance in the glaze. And the unglazed parts of the pottery become carbonized and blackened.

https://www.2000cranes.com/_artists/Raku/aka-raku.jpg

Raku process originated in Japan For more information read on your own : Raku History

Japanese raku pottery refers to an ancient tradition. It refers to the making of tea bowls using particular techniques of forming and firing the clay. This tradition has been practiced and preserved by successive generations of the Raku Family for over 500 years.

The adoption of the word raku to refer to western techniques does feel uncomfortable. When I started to learn about raku, I learned about western practices. It is only with hindsight that I’ve begun learning about Japanese raku pottery. It does seem as if the term has been if not hijacked by the west, then co-opted. Nevertheless, it’s good to understand the differences and appreciate the beauty of Japanese raku ware.

Sourced from:

https://thepotterywheel.com/japanese-raku-pottery/

You can read more about the history and evolution of raku here: https://thepotterywheel.com/japanese-raku-pottery/

ASSIGNMENT 1:

PART 1: In class - watch the stages of clay video below

and note the stages of clay in your lab book (10 pts).

RUBRIC: STAGES OF CLAY

______ /2 Sketchbook entry is titled "Stages of Clay"

______ /6 All stages of clay are listed with a definition for each

______ /2 entry is neat and legible

https://www.youtube.com/watch?v=MbarydH0FU8

1700s-1850s Japanese Tokoname Pottery Edo Period/Tsubo Jar Vessel Vase Wabi Sabi

Wabi-abi In traditional Japanese aesthetics, wabi-sabi (侘寂) is a world view centered on the acceptance of transience and imperfection. The aesthetic is sometimes described as one of beauty that is "imperfect, impermanent, and incomplete". It is a concept derived from the Buddhist teaching of the three marks of existence (三法印 sanbōin), specifically impermanence (無常 mujō), suffering (苦 ku) and emptiness or absence of self-nature (空 kū). Characteristics of the wabi-sabi aesthetic include asymmetry, roughness, simplicity, economy, austerity, modesty, intimacy, and appreciation of the ingenuous integrity of natural objects and processes.

ASSIGNMENT: Build a pinch /coil pot that is organic (based on a natural form is one approach) and asymmetrical in form.

Pinch Pot Examples : https://www.pinterest.com/jennym0284/pinch-pots/

PLANNING: In your journal make 3 sketches for potential pinch pot designs.

Assignment Part B - Wed and Thurs Sept 18 + 19

Watch: