Glossary of Terms Common to Chavant Clays
Adhesion - The ability for a product to stick to other, non-similar, materials.
Aging - Clay has a life cycle that can sometimes be accelerated. Aging can describe physical changes in clay over time.
Armature - The substructure that supports a clay model.
Billet - A billet, offered as blocks or cylinders, is the finished extruded form that the clay is packaged in. The approximate size of the block billet forms are 1 pound blocks, 1" x 4" x 4"; 2 pound blocks, 2 ¾" x 2 ¾" x 5½"; 5 pound blocks, 5 ¾" x 5 ¾" x 6; and 10 pound blocks 5 ¾" x 5 ¾" x 12". The approximate size of the cylinder billets are 2 ½" x 12" (2 ½ pounds each); 3" x 8" (3 pounds each); and 3" x 16" (6 pounds each).
Burning Clay - Used when describing overheating clay in a warming device or by the exothermic reaction created by some mold making materials.
Cast - The positive form that reproduces the negative shape of a mold taken from the positive clay pattern. The cast will be an exact duplicate of the clay model.
Clay Body - A term used to describe different clay formulas with different characteristics.
Cohesion - The ability for a product to stick to itself or similar materials.
Consistency - The uniform or homogenous properties within an individual clay body. Also used to compare similar qualities from production batch to production batch.
DeAired - A process of clay extrusion. By running a clay through the DeAiring process, a clay becomes smoother and more homogenous. This procedure is a vigorous mixing cycle that reduces ingredient particle size and removes entrapped air, creating a finished product that has a somewhat higher density.
Extrusion - Process of forcing clay through a pre-cut die shape.
Filler - Inert material mixed together with other clay ingredients to create the clay body base.
Fine Art Clay - Clay used in the Fine Arts field for sculpture.
Firmness - A value, from 1 - 10, associated to the room temperature hardness of clay, with "1" being the softest clay and "10" being the hardest clay.
Industrial Design Clay - (Hard Styling Clay) Clay developed for use by Industrial or Product designers. Has the ability to hold exacting detail and to be polished to a glasslike finish. Template shapes can be pulled through Industrial Design clay to create an accurately reproduced, dimensionally stable shape. Industrial Clays can also be milled.
Length - The ability of a clay body to stretch, bend or twist. If you were to roll clay into a pencil shape and stretch it, sometimes it will fracture, other times it will pull apart and eventually split in a "taffy" like point. Greater length means more flexibility.
Melting point - The temperature where a clay body becomes fluid.
Mold Making - The process of reproducing a negative form from a positive shape of clay. Flexible mold making materials include urethane, silicone, latex and polysulfide rubbers. Rigid mold making materials include plaster and fiberglass.
Non Hazardous - Chavant has had its clays certified by the ACMI (Art & Creative Material Institute). The ACMI definition is "Products bearing the AP approved Product Seal of ACMI are certified in a program of toxicological evaluation by a medical expert to contain no materials in sufficient quantities to be toxic or injurious to humans or to cause acute or chronic health problems. ACMI's Toxicological Board regularly reviews this program. These products are certified by ACMI to be labeled in accordance with the chronic hazard labeling standard, ASTM-4236 and Federal Law, P.L. 100-695. In addition, there is no physical hazard as defined within 29 CFR Part 1910.1200 (c)."
Non Toxic - See Non Hazardous.
Oxidation - A reaction between oxygen and the surface of the clay, typically noticed as a hardening of the immediate surface of the clay. Higher temperatures, especially in clay ovens often accelerate oxidation.
Penetration - The value, representing the distance a needle will push into clay at various temperatures. Chavant will refer to the Firmness of a clay body.
Plasteline, Plastilina, Plasticine - A generic term to identify oil based sculpting clay from other types of clay.
Plastisizer - Lubricant in clay to assist in moisture retention and flexibility.
Release Agents - Products used to prevent mold making materials from sticking to clay models or to prevent cast parts from sticking in the mold.
Sealers - Products used to incorporate a protective film (Barrier) over the clay, which will prevent a mold making material or other product, such as a paint, from coming into direct contact with the clay. Sealers can include shellac, lacquer or clear acrylic finishes.
Shelf Life - Period of time before a product will lose some of its useful characteristics.
Slick - A tool with rounded edges, made of polycarbonate or lexan, used to smooth the surface of a Hard Styling Clay model.
Splash Mold - A mold taken from only an isolated portion of a model.
Sulphur Based - Sulphur is a non-toxic filler used in many modeling clays. It provides a silky, unique feel to the clay, is readily available and its price is reasonably stable. Sulphur based sculpting clays produced by Chavant include Professional Plasteline and DaVinci. Industrial clays (often used by sculptors) which contain sulphur include CM-50, J-525, CM-70, I-305, I-307 and J-88.
Sulphur Free - A clay body absent of sulphur. Sulphur Free clays produced by Chavant include the NSP product line, the Le Beau Touché product line and P-40.
Surface Development - Clay surfaces can be modified by using various tools or fluid materials. Polished Lexan slicks can be used for highlighting Hard Styling Clays and many solvents can be used to smooth the Fine
Surface Plate - A perfectly level working area often with precisely measured grid markings used for coordinate measuring.
Template - A predetermined shape cut into various materials including aluminum, Masonite or Lexan, which is pulled through the clay to transfer the shape into the clay.
Warming techniques - Any method of heating clay to create a softer consistency. Most Plasteline is wax based therefore warmer temperatures will soften the wax. Typical temperature ranges to soften clay are 110° F to 145°F and many options exist to purchase or construct a "clay warmer". Successful methods of clay warmer construction include many variations of any box with a light bulb as a heat source. Light bulb wattage may range from 25 watt to 100 watt and it is common to have more than one bulb and more than one wattage. Dimmer switches are often put "in-line" to regulate heat. Many good ovens have been made from old refrigerators! Restaurant bun warmers work well and specialty lab ovens are available.
Working Temperature - Generally the temperature where clay is considered soft enough to comfortably work or apply by hand. This temperature can range from room temperature to 150° F depending on the formulation. Also used to describe the temperature considered best for pulling templates through clay or machine milling clay