Properties of paper clay:

You can make paper clay out of any clay body that you are currently using. Paper clay increases the dry strength of the body so that moving large pieces is less of a problem. Paper in the clay “opens” up the clay body so that you could work with much thicker walls for sculptural forms. Water vapor will escape the walls because of the paper; the threat of exploding walls is reduced.

When working on sculptural forms, you can add multi-layers of clay. These additions can be added at any point in the forming process. You can add wet-to-wet, wet-to-dry, or wet-to-bisque. (Yes, you can add wet clay to bisque and re-fire the piece.) Paper clay will withstand multiple re-dampening to make changes in the form. Paper clay will withstand forced drying. Paper clay allows for late stage additions to a piece. Even when dry, paper clay will stick to the form and allow changes. It is easy to cut a handle off a piece and reattach a better handle.

The fired results of paper clay are the same as regular clay. The piece will be lighter, and will shrink a little more that standard clay. Ash from the paper, and borax in the cellulose will act as a slight flux in the clay body. Use a cone 10 porcelain body and fire to cone 6 to correct for the flux problem. No change in formulation is necessary for stoneware or earthenware.

Short paper fibers are better than long fibers. Long fibers, or even other materials such as nylon or fiberglass do not add advantages to the clay. They are hard to cut and decrease workability. Don’t use glossy or color papers in paper clay. Ink used on newsprint will not add color to the fired clay.

Paper clay reduces the weight of the clay body because the paper replaces part of the clay with the lighter paper fibers.

Paper clay can be used on the wheel. But, a better ides is to use the regular clay on the wheel and use paper clay if you attach any handbuilt additions to the form. Handles made out of paper clay are less likely to crack and the paper helps bind them to the surface.

Paper clay slip is very good joining glue when handbuilding forms. The paper fibers in the clay increase the strength of the dry bond.

Paper clay can be used a repair material for cracked pots. (It’s usually better to discard a broken pot and spend your time making a better one!) The clay, along with paper slip can be forced into the crack for a repair. The paper helps to hold the patch in place and increased the bond of the repair.

Paper when added to clay in the amounts listed in this paper will not cause damage to an electric kiln. Increased amounts of cellulose, fired in a bisque kiln at a fast rate could cause a small amount of smoke in the kiln room. If this is a problem, reduce the amount of paper fiber in the clay, or fire the kiln at a slower rate for the first 1/3 of the firing. Adequate ventilation is important in all kiln firings. In most cases, the addition of pieces containing paper will not make any noticeable difference in the firing process.

Sources of cellulose insulation can be obtained through local insulation distributors. Look in your local phone directory yellow pagers under insulation. Call local insulation installers and ask to purchase a bag of insulation. Of the large building materials sellers in the Philadelphia area only Lows sells cellulose insulation. One bag of insulation will last you a very long time! (At the Clay Studio in Philadelphia, one bag of cellulose lasted over a year with several people using it)