Polyclay Basics by Donna Kato Polymer clays are man made modeling materials that, once heat cured, become permanent and will not return to their original state. All are composed of the same basic componenets: plasticizers, resins, fillers and colorants. Before using polymer clay it must be conditioned ... knead by hand until the clay is soft and pliable or fold and roll through a pasta machine. Inadequate conditioning will result in weakened finished items and poor piece to piece adhesion. Condition light colors first, then darker colors. Polymer clay pieces can be cured in a standard oven (convection) or toaster oven. Do not microwave polymer clay. If you don't have a dedicated oven, place items in an aluminum pan, then cover tightly with foil to prevent residue build up in your oven. Cure pieces in a well ventilated area. Check oven accuracy with a thermometer and use a timer to avoid exceeding curing time. Cure at 275F (135C) for 30 minutes per 1/4" of thickness. When making large items, cover armature material, such as compressed foil, with clay. Clay walls should not exceed 1" thick. Do not use styrofoam as an armature material. Materials that will withstand clay curing temperatures, such as glass, paper mache, wood, metal and ceramic items may be covered with clay and baked in the oven. Items may be nested in polyester batting to avoid flat, shiny spots. Finished pieces may be painted or glazed after curing. Waterbased paints and glazes are recommended. Cured clay may also be wet sanded (automotive sandpaper (400-600 grit, in water) and then buffed to a high gloss sheen. Kato Polyclay is intended for decorative use only - not for food bearing items. Tools used for clay should be dedicated to clay use only. Clean hands with alcohol saturated paper toweling or alcohol towelettes, then finish with soap and water. Always clean hands before eating. Store clay in cool, dry place away from direct sunlight. Wrap unused clay in plastic wrap. Kato Polyclay is certified AP non-toxic and conforms to ASTM D 4236.