Chapter 5 of Ceramics: A Potter’s Handbook covers clay in the studio, stating that, “clay is the basis of everything that the potter makes, yet seldom do we use clay straight from the ground.” This statement sets the reader up for the contents of the chapter, such as clay bodies and preparing clay to be used in the studio. Clay bodies that are perfect for the potter rarely comes ready made from the earth. Though it lacks the ready-made quality, it can be added to get a clay body that is just right for each project. Grog, crushed, fired clay, is added to add porosity to the clay, allowing it to dry uniformly. A clay that is extremely fine, or fat, has grog added to it. A clay can lack fluxes, which allow it to be fired at certain temperatures,
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Raku bodies are prepared for firing differently, due to the speed of raku firing. Thinner, more open ware has a higher cnace of surviving a raku firing. The raku body is typically stoneware with at least 20 percent grog, adding porosity. The expansion due to the heat and the contraction of cooling happens during the rapid firing of the raku process, are part of thermal expansion. The faster the clay cools, the more cracks in the glaze, called crazing. Sculpture bodies tend to be made for larger, thicker work. Grog is added, along with plastic, coarser, fireclays help the sculpture stand and support itself. The grog added to the sculpture body varies in particle size, allowing to reduce shrinking. A possible addition to sculpture bodies is nylon fiver, allowing an increase in plastic strength. The nylon can burn out of the clay during bisque firing. Nylon net can also be put in between two slabs of clay, increasing strength. Though it is possible to add these to clay, this clay should not be recycled, and should not be run through clay processing machinery. Ovenware and flameware bodies can be used for cooking in and the mix can be formulated with quartz inversion effects to make the piece more resistant to heat shock at lower temperatures. Casting slips allows the clay to be poured into a mold. The slip buts be deflocculated to allow liquefying with only slightly more water than when used in throwing. Clay bodies such as porcelain are commonly used for slip. The amount that the potter makes of the slip must be tester for deflocculating amounts. Colorants in the clay bodies are due to impurities in the clay, such as iron oxide creating a red hue in the clay. A large amount of iron oxide can also cause staining with whatever it comes in contact with during forming. Certain materials may be
Raku bodies are prepared for firing differently, due to the speed of raku firing. Thinner, more open ware has a higher cnace of surviving a raku firing. The raku body is typically stoneware with at least 20 percent grog, adding porosity. The expansion due to the heat and the contraction of cooling happens during the rapid firing of the raku process, are part of thermal expansion. The faster the clay cools, the more cracks in the glaze, called crazing. Sculpture bodies tend to be made for larger, thicker work. Grog is added, along with plastic, coarser, fireclays help the sculpture stand and support itself. The grog added to the sculpture body varies in particle size, allowing to reduce shrinking. A possible addition to sculpture bodies is nylon fiver, allowing an increase in plastic strength. The nylon can burn out of the clay during bisque firing. Nylon net can also be put in between two slabs of clay, increasing strength. Though it is possible to add these to clay, this clay should not be recycled, and should not be run through clay processing machinery. Ovenware and flameware bodies can be used for cooking in and the mix can be formulated with quartz inversion effects to make the piece more resistant to heat shock at lower temperatures. Casting slips allows the clay to be poured into a mold. The slip buts be deflocculated to allow liquefying with only slightly more water than when used in throwing. Clay bodies such as porcelain are commonly used for slip. The amount that the potter makes of the slip must be tester for deflocculating amounts. Colorants in the clay bodies are due to impurities in the clay, such as iron oxide creating a red hue in the clay. A large amount of iron oxide can also cause staining with whatever it comes in contact with during forming. Certain materials may be