Acid Bath - A term used in heat treating and tempering of steel.
Acrylic - A thermoplastic resin, created by mixing proportionate parts of plastic components together, used for cast and molded parts; can be clear or colored.
Adalox Paper - Trade name of Norton Co. Grit paper of Carborundum ranging in mesh from 220 to 1200 used for sanding and finishing. The higher the number, the finer the grit.
Adz - Type of double-sided swing tool used to reduce large geometric areas from logs.
Aging - The process wherein a molecular change occurs with a moist or oil-base clay causing a physical reaction to the nature of the material.
Air Floated - A process that eliminates foreign particles from a clay body, making it pure or refined.
Alabaster - A gypsum stone indigenous to Spain, Italy, and the Northwest United States. It can be opaque, translucent, colored, or banded; a dense calcite. A medium-grade carving stone.
Alcohol - Colorless flammable liquid used as a thinning agent or solvent; used to thin or remove shellac from a model.
Alcohol Lamp - Used to heat modeling tools for wax detailing; alcohol fueled with wick or possible spout for flame direction.
Alginate - A derivative of marine algae used in mold making and casting; used for small flat items only because of its tendency to tear or rip.
Alloy - Metal compounds fused together when molten to form bronze for casting. Different component parts will result in different types of bronze.
Almaloy Wire – Also known as aluminum wire. Pliable aluminum wire used for internal support of sculptures; in gauges ranging from 1/16 inches to 3/8 inches.
Aluminum - Malleable light silver-colored metal that resists oxidation (discoloration such as patina).
Amorphous - Having no defined shape or form such as free form sculpture.

Anatomical - Structural make-up of human or animal body parts.
Anneal - To heat and cool steel so that the metal is not brittle.
Apron - Generally cotton, duck, canvas or leather used for protection against clay, plaster and dirt in the classroom or studio.
Arch - To form or bend into a desired shape as in architecture.
Argillaceous - Containing clay or clay minerals.
Arc Welding - Molding steel or metal with electrical current.
Arkansas Stone – Sharpening stone used to hone wood and stone carving tools
Armature - An internal support to hold the outer covering of a sculpture; may be made of various materials such as wood, wax, steel, but generally almaloy or aluminum wire.
Armature Wire – See Almaloy Wire.
Art Plaster - Trade name of U.S. Gypsum Co. A gypsum material with an extremely high absorption rate primarily used in ceramic slip casting molds.
Artware - Trade name of Sculpture House Inc.; a low-fire ceramic moist clay that vitrifies at Cone 04.
Atelier - Studio or workshop, usually of an artist, derived from French.
Autoclave – Apparatus in which using superheated steam under extreme pressure for purification purposes.
Aventurine - A type of translucent quartz with traces of mica throughout.
Ball Bearing - A turntable, like a lazy Susan, with hardened steel balls, designed to allow easy movement.
Ball Clay - Base clay for earthenware ceramic clay formulas.
Ball Mill - Grinding device used to mill clay and glazes, with balls rotating in a container.
Banding Wheel - A rotary top on a post or ball bearing that allows clay or a sculpture to be easily turned for working or decorating.
Barium - Silver-white metallic element of alkaline earth; a toxic material used as a pigment or extender.
Base - Holding support for the display of a finished piece of sculpture.
Basic Carving - The primary removal of clay, wood, stone, or other sculpting material to create a basic geometric shape.
Bas Relief - A sculpture that is slightly raised with no apparent undercuts.
BAZ - Trade name of Sculpture House Inc.; basic stone carving tool set consisting of chisels and one mallet, in a canvas roll.
Beeswax - A pure yellow natural wax used to dress wood or seal stone sculpture; also used in batik.
Bench Screw - A double screw device that holds a carving block of wood secure for carving; screws into the block and into the securing device.
Bench Stone - A sharpening stone, possibly of various grits, used to sharpen and hone tools.
Bentonite - An absorbing clay used as a filler in clay bodies.
Binder - A clay or wax material that enables other materials to adhere when they normally would not.
Bisque - The first firing of a clay or ceramic piece before glazing. Typical bisque firing is Cone 04 - 06.
Black Rubber - Also known as “Tuffy,” a three-part polysulfide rubber used for professional mold making.
Blanks - In wood and stone carving, pieces of steel not yet forged.
Blistering - Term used when a glaze overheats and causes bubbles to form on the pottery.
Blocked Bust - Head and shoulder cast showing the basic geometric planes of a figure; usually made of hollow cast plaster for study.
Blocked Mask - Face mask showing the basic geometric planes of the facial structure.
Block Scraper - Rectangular steel scraping device used in leveling and cleaning molds. Length can vary; can be used with or without teeth.
Bluing - A water-soluble pigment used in the initial cast of a plaster waste mold to alert the mold maker to the closeness of the cast.
Bonded Bronze - A polymer resin mixed with bronze powder to give the feel and simulated weight of a bronze cast without the expense.
Bone China - Translucent white china made with bone ash and clay.
Bone Emulsion - Trade name of Sculpture House Inc.; a liquid which when mixed with plaster adds strength to the plaster.
Boneware - Trade name of Sculpture House Inc.; a pure self-hardening clay in red, white and gray. Used for direct modeling or in plaster press molds.
Boxwood Tool - A modeling tool formerly made of a wood named “boxwood”; in a variety of shapes and lengths, these tools today may or may not now be made of boxwood but of a similar hardwood.
Brass - Alloy consisting of copper and zinc.
Brazing - Joining of metals by use of heat.
Bronze - A combination of copper and tin; the compound may vary in proportions of each.
Bronze Rod - A bronze material used for brazing a joint or doing repair work on a bronze casting.
Bruise - Term most commonly used in stone carving. When a piece is dropped on a hard surface, discoloration or imperfection appears on the surface where the stone made contact.
Brush - A wire or bristle material used in cleaning the interior of molds and in the application of patina on a piece of sculpture.
Bubbling - Caused by the overheating or high temperature of a kiln during glaze firing of pottery.
Burl - Hard woody hemispherical outgrowth on a tree.
Burlap - An open mesh cloth used in reinforcing molds and sculptures; most commonly impregnated with plaster.
Burma Slip - Slip stone made of Burma stone used for sharpening tools.
Burner - Flame producing burning device such as an oven.
Burnout - The process in which wax is burned from a ceramic shell mold so that molten metal such as bronze may be poured.
Bush Hammer - A cross checked steel hammer used to reduce large sections of stone.
Bush Pick - Tool, one end a bush hammer and the opposite end a straight pick; the striking end comes to a point.

Cabinet Rasps - Medium coarse rasps with teeth attached to a handle of wood; used for reducing and finishing wood and stone.
Cadmium - Ductile malleable material used as a protective coating on steel rasps.
Calcium - Silver-white metallic element of alkaline earth.
Calipers - A device of wood or aluminum, generally curved, used for measuring dimensions of a piece for reproduction.
Caped Chisel - A round end stone carving tool used to make gouges or furls like a cornfield.
Carbide - Binary element of carbon with a more electropositive element; extremely hard, brittle metal.
Carbide Tools - Tools with carbide cutting edges brazed and sharpened as tips for longer lasting use without repeated sharpening.
Carburize - To combine or impregnate with carbon; a flame produces the carbon effect on metal.
Carrara - A small town in Italy where the Carrara marble quarries are found.
Carrara Marble - An Italian stone, in varying grades of color, indigenous to Carrara, Italy; used by Michelangelo
Carving - The act of shaping stone, wood, and plaster by cutting with specially designed tools.
Carving Chisel - A flat, high carbon steel tool, with a flat sharp cutting surface used with a hammer or mallet to carve stone, wood, or plaster. Sweep and width vary with size of the tool and the bevel is at different angles for wood or stone tools.
Carving Tools - Tools used in forming wood, stone, wax, plaster, or clay pieces. Can be made from high carbon steel, most commonly used in wood carving and stone carving.
Case Mold - A mold usually constructed as a retaining mold for casting slip.
Cast - A reproduction of an original piece of sculpture in any number of casting materials, most commonly plaster, plastic, or bronze.
Casting - The process that duplicates a model or piece by pouring casting material into a pre- formed mold.
Casting, Investment - Process whereby a model is covered with a ceramic shell investment for the pouring of bronze. This investment or ceramic shell can withstand the high temperature of the molten bronze, whereas other materials cannot.
Casting Plaster - A gypsum product most commonly used in casting sculpture. Produced by U.S. Gypsum Co. specifically for casting. It is unlike plaster of Paris which is a commercial more porous plaster used in plasterboard in the housing industry.
Casting Rubber - A latex rubber that is cast into a plaster mold to achieve a positive cast. Flexibility (hardness) from rubber band flexible to wood hard rigid can be increased or decreased by using a filler in proportionate amounts.
Cast Stone - A powder containing marble aggregate and several types of gypsum. When mixed properly with water and cast into a mold, it resembles Noxus marble from Greece.
Cavity, Hollow Mold - A type of mold made with a mother mold with a retaining blanket over an original model. Once removed and the outer shell mold replaced, a hollow cavity is formed where a chemically activated rubber may be poured into the resulting hollow cavity thus creating a flexible rubber mold.
Cement - A powder of alumina, silica, lime, iron oxide, and magnesia burned together and pulverized to make mortar or concrete.
Centigrade - Temperature range from 0° (freezing) to 100° (boiling). Normally used when casting bronze or polyurethane plastic where temperature will affect the mold material when cast.
Centimeter - Unit of length within the metric system.
Centrifugal - Acting away from the center forcing material outward.
Centrifugal Casting - Small sculpture or castings made with a centrifugal mold by spinning molten material.
Ceramic - A clay material such as earthenware or porcelain made of a non-metallic mineral fired at high temperature.
Ceramic Shell - A slurry coating over a wax model; in the bronze casting process the wax is burned or melted out enabling bronze to be poured, while molten, creating the bronze cast .
Ceramist - A person engaging in ceramics, either casting greenware or making pottery.
Cesta - Nylon reinforced basket or pail with double handles, made of black rubber, used in mold making and casting.
Chasing - Hammering or shaping rough areas or seam lines. Usually associated with bronze work.
Checking - Cracking caused by the absorption or evaporation of moisture in wood products.
Cherry Red - Color of metal achieved in forging or heat treating steel.
Chimney - Flue of an exhaust vent in an oven to release gas and fumes.
Chip Carving - Type of wood working done with handheld palm grip tools.
Chipping- Striking a piece of wood or stone with a tool and/or hammer causing the basic geometric form to change.
Chisel - A stone, plaster, or wood working tool with a flat straight edge. Usually beveled at 45° on one or both sides.
Chromium - Chemical used in electroplating metals.
Chuck - Area that holds the shank or end of a grinding burr or handpiece.
Claw - In stone carving, a tooth chisel.
Clay - Earthen material that is plastic when moist and hard when fired, used in pottery and ceramics.
Clay Bodies - Formulas of different base clays and binders that create moist clays in specific colors, firing ranges, and consistency. Usually developed by ceramists as private formulas.
Clay Fence - A separating line usually 1 inch high by 1/8 inch wide, used to divide a model into sections for the mold making process.
Clay Flour - Dried and refined air floated natural clay in the dry state (powder). Gathered from primary indigenous regions of the world having specific characteristics particular to earthenware, stoneware, porcelain, etc.
Claystone - Trade name of Sculpture House, Inc. Self-hardening clay with cornstarch hardener and cotton fiber filler to decrease shrinkage and cracking while drying over an armature.
Clay Wall - A separating device in mold making. See Clay Fence.
Clay Water - A thin liquid mixture of clay flour and water used as a release in casting and mold making.
Clean Clay - A soft oil-base modeling clay without sulfur.
Clean Up Tools - Different shaped scraping tools used in the removal of seam lines on slip cast pieces.
Cobalt - Greenish blue pigment used in ceramics to color glazes. Contained in silver ore.
Cold Cast - Casting done with plastic polymers or resin. Also casting done with a mixture of bronze powder to simulate bronze.
Cold Pour Rubber - A casting rubber of urethane, usually mixed in three stages using a catalyst that chemically cures rather than air cures. Also known as Black Tuffy, or Cold Pour Mold Rubber.
Collet - Device used in securing the shank of different size burrs, either increasing availability or reducing availability, as needed, to fit a handpiece shaft.
Colorado Marble - A white crystalline marble, or Yule marble, of medium hardness with very little veining, indigenous to northern Colorado.
Compound - Mixture of different materials to form a mass used in buffing or polishing. Can be different degrees of coarseness.
Cone - A triangular-shaped heat testing device used in the ceramic firing process. Cones melt at different degrees of temperature indicating the internal temperature of the kiln, and sometimes activating a shut-off device within the kiln to turn the heat off at a specific temperature to prevent over-firing the contents.
Contamination - Occurs when foreign material is introduced to a given process. For example, plaster residue in a clay ceramic piece which causes an explosion in the kiln while firing.
Copper - Reddish metallic element that is malleable, and conducts heat and electricity well.
Core - The center of the mold.
Core Pin - Device that holds the core in place while making a casting.
Cornwall Stone - A type of clay flour used in private or special clay formulas for a specific effect.
Corrosion - A natural hemispheric effect caused by water and oxygen that may result in pitting or discoloration.
Crackle - A hairline cracking or shattering effect caused by the shrinkage of glaze from pottery and ceramic pieces during firing. Generally caused by incompatibility of the clay contents.
Crawling - Occurs when glaze has been over-applied and runs in pools during the firing process. Or spider web effect or cracking caused by the improper fit of glaze to the clay. Glaze does not shrink with the clay.
Crosshatch - Scoring with perpendicular cuts in a checker board fashion, commonly used in wood working or, at times, in stone carving.
Crucible - Container used to hold molten metal for pouring or centrifugal casting.
Crystallization - The act of becoming crystalline in form
Custom Tools - Tools made to individual specifications to fit a customer’s special needs or requirements, used with stone, clay, and/or plastilina.
Damp Closet - A container used to store moist clay to preserve its pliability.
De-Air - To remove air from a moist ceramic pottery clay body with vacuum compression.
Decant - To pour from one vessel to another.
Decomposition - To separate into simpler parts.
De-gas - To remove vapor or gas from molten metal before casting.
Dehydration - The removal of bound water.
Della Robbia - Trade name of Sculpture House, Inc. A self-hardening clay that can be fired in a kitchen oven at low temperatures; for decorative use only, nonfunctional pottery.
Denatured - Term describing alcohol which is unfit for consumption due to modification by heating. Used in mold making and casting.
Density - The mass of a substance per unit volume. Usually used in determining amounts of clay required for a project or a piece. Mathematically determine the total cubic inches of the piece to be made (height times weight times depth). One ounce of material equals one cubic inch.
De-oxidation - The removal of oxygen as in reduction firing in ceramics to achieve a specific effect.
De-vitrify - To deprive of glassy luster and transparency. To change from a glassy to a crystalline condition.
De-waxing - Removing the wax model from a mold; usually accomplished with heat.
Dextrin - A sticky starch used in adhesives; also used in self-hardening clays.
Die - A device to create multiples of an original by stamping or pressing. Usually made of tool steel with a male and female half.
Dipping - The process in mold making or glazing ceramics in which a piece is submerged to give it a coating.
Dipping Tongs - In ceramics, a tool to hold pottery when dipping it into a glaze solution prior to firing.
Direct Carving - When the final piece is sculpted from an original source, usually in wood, stone, and wax carving.
Dolomite - Ceramic base material used to enhance plasticity in ceramic clay bodies.
Double Wire End - A tool made with cutting wires on each end with a wooden or metal tapered handle to secure the two working ends; used in clay modeling and plaster work.
Draft - Occurs in kiln firing to control temperature in down draft kilns.
Draw Knife - A flat or concave beveled blade with perpendicular handles so that the blade can be drawn or pulled toward the body of the user. Used in boat making and wood carving.
Dremel Tool - Trade name of Dremel Company. Electrical power tools that turn at high speed in a rotary motion, used for grinding, shaping, and finishing.
Dresden Clay - Trade name of Sculpture House, Inc. An English talc pottery clay that contains grog.
Dryness, Short - When a mixture contains too much clay flour in proportion to its liquid bonding agent, in either water-base or oil-base materials.
Ductile - Capable of being fashioned into a new form, as in aluminum wire or almaloy wire.
Duron Modeling Tools - Plastic modeling tools made by injection molding to make different shaped plastic modeling tools. Owned by Sculpture House, Inc.
Dust Mask - Face device, in styles ranging from cotton gauze to cylinder cartridge containers, to protect against inhalation of dust and fumes while mold making and casting.
Dye - A coloration used in waste mold casting to determine when the removal mold is coming close to the cast piece, thus preventing damage to the cast.
Earthenware Clay - Slightly porous clay fired at low temperatures.
Eldorado Stand - Trade name of Sculpture House, Inc. A medium strength modeling stand with gear crank raising and lowering device, three-legged, collapsible, can hold 200 pounds of working material.
Electric Wheel - Potter’s wheel run by electricity either at fixed variable speeds or with variable speed foot pedals. May be run with belts or cones; can throw up to 50 or more pounds of clay at one time. Specifications will vary with the manufacturer.
Electrode - A conductor used to establish electrical contact with a nonmetallic part or circuit.
Electrolyte - A nonmetallic electrical conductor in which current is carried by the movement of ions. Used in electroplating castings.
Enameling - Covering, inlaying, or decorating with a colorful surface by fusion of an opaque, nitrous composition to metal.
Epoxy Resin - A multiple-part casting material; when mixed with a catalyst, it becomes hard plastic.
Epsom Salt - Colorless white crystalline salt, hydrate magnesium sulfate with cathartic properties. Used with ceramic glaze and in firing techniques.
Extruding - Mixing and forming clay or plastilina into rounds or squares for storage to allow the molecular structure to migrate.
Face Shield - A clear curved plastic protection device with movable shield worn over the head to protect the face and neck from debris while carving stone or wood.
Fahrenheit - A thermometric scale. Boiling point is 212° above zero, freezing point is 32°.
Fat, Fatty - In working with clay and ceramics, indicates a texture resulting from excessive bentonite or water, making the material difficult to control.
Fat Oil - Oil derived from animals; has a high acid content.
Feldspar - Constituent of nearly all crystalline rock with aluminum silicates. Used in the ceramic field.
Female - The negative half of a mold or die.
Fettling - Shaping an object.
Fettling Knife - A tool designed to shape and texture models in sculpture and pottery.
Fiberglass - Glass in a fibrous form used in making casts that are light weight but strong.
Fifth Wheel - A heavy gauge ball bearing device from 12 to 36 inches in diameter used to hold and turn heavy pieces of sculpture; sometimes used as a table turning mechanism to rotate live models for sculpture classes. In the early 1900’s used to turn trains around to head them back in the direction from which they came.
File - Tool with cutting ridges used to shape sculptures in stone, wood, plaster and resin. These cutting edges are usually cross cut rather than punched, forming small ground cutting surfaces.
Filler - Ingredient which when added to a base material bonds or strengthens the mixture.
Fimo - A self-hardening cellulose body of light weight that dries white.
Fine Cut Rasps - Smoothing and finishing tools that have close cut surfaces for extra fine finishing in the last stages of reduction.
Finishing Material - Sanding, rasping, or buffing compounds used in the final stages of sculpture.
Firebox - Chamber that contains a heated area such as a kiln.
Fire Brick - The insulating brick or interior walls of ceramic kilns used in firing pottery.
Fire Clay - Clay that can withstand the high temperatures used in ceramics and pottery. Also used to make fire brick for the interior walls of ceramic kilns.
Firing - The process of heating ceramic clay to a temperature at which the particles merge and become hard. In glazes the dried material liquefies and becomes glasslike when cooled. With clay the material becomes non-porous in its final state, not always necessary when firing pottery.
Firing Range - The temperature that a clay can withstand without distortion or warping either in the bisque or glaze firing; generally in cone ranges 014 to 10, temperatures from 1418°F to 2345°F. The point at which vitrification occurs (merging of the molecular structure) as stated in cone number.
Firing Scale - The temperatures at which different clays can be fired, given in cone ranges.
Firmer - In wood working a type of chisel with a thin flat blade cut at an angle.
Fish Tail - A wood working tool where the sweep or cutting edge fans out on both sides, resembling a fish tail.
Fissure - Break or crack, in stone carving and sometimes in bronze casting.
Fit, Clay/Glaze - When a ceramic glaze adapts well to a certain clay body without grazing, cracking or pooling. It can be a long experimental process to find a fit, especially with special formula clays and glazes.
Fitch - Section of wood prepared to be dried prior to carving. It is usually sealed and arranged so moisture evaporates naturally to prevent checking (cracking) in the future.
Flaking - Pieces of fired glaze chipping off pottery after firing, usually caused by incompatible clay and glaze.
Flashing - A web-like residue on casting material where the seam lines meet and the casting material has escaped, common in most castings (bronze, slip, and plaster casting). The flashing is removed by cutting, scraping, and finishing.
Flash Point - The temperature at which an item or material will combust. In sculpture used when working with wax or bronze.
Flat Chisel - A tool with a straight flat cutting edge used in wood and stone carving.
Flaw - Defect in a cast or forging, (even a stone), that renders the material unusable.
Flexible Bowls - Rubber bowls of varying diameters and sizes used in mixing plaster for casting and for repair work. Casting material is easily removed by flexing the bowl.
Flexible Mold - A mold that can be removed from a cast by stretching.
Flexible Paint - Paint that expands and contracts with an elastic effect when applied to a rubber casting. Usually sprayed on a movable object where flexibility is desired.
Flexible Pallet - A thin scraping device used in mold making, casting, and ceramics to smooth the surface of wet plaster or moist clay.
Flexite Gelatin - Flexible reusable horsehide glue. Used in the production of hollow cavity molds in the early 1900’s; use of the material has been discontinued in mold making and casting.
Flint - Mass hard quartz, used as a binder in clay bodies.
Flourspar - Used as a flux in making glazes.
Fluidizing - Making flow like a liquid, as in mixing plaster or ceramic slip for casting.
Flux - A substance used to promote fusion in ceramic and welding bronze sections of a mold.
Footing - Bottom section of a piece of pottery generally raised from the base of the pot or bowl.
Foredom Tool - Trade name of Foredom Electric, Co. Electric, rotating, variable speed, heavy duty grinding machine with interchangeable handpieces. Motors are available in different R.P.M.’s and horsepower.
Forge - Oven in which tools or metal are heated making them easy to shape to specific designs. The process by which a tool for working in stone, wood, plaster or wax is heated and shaped.
Form - To shape to resemble a vision of thought or sight. Free form is an unconventional shape inspired by an inner vision.
Formula - A combination of different materials blended to achieve a desired effect in clay, wax, plastilina, and glazes.
Foundry - A studio wherein molten metal, usually bronze, is cast into sculpture.
Fracture - To break or go beyond the limits or tolerance of an object, usually occurring in bronze casting or ceramic firing. Can also be a break in a boulder to be used in stone carving.
French Clay - Known to sculptors of the early 1900’s as a fine quality smooth modeling clay for marquees or models of their sculpture. Replaced in the 1990’s by Hugo Grey Moist Clay.
Frit - A component used in making glaze and glass of varying meshes and colors.
Frosting Tool - Tool with multiple pointed cutting edges on a squared surface, somewhat like a waffle iron, mounted on a hammer type handle. It may vary in dimensions from ½ to 2 inches. Its primary use is to reduce stone for sculpture.
Fuller’s Earth - A clay that lacks plasticity, used as a filler in certain clay bodies to bind other plastic clays together.
Furnace - A chamber used to fire pottery or enamels at high temperatures. Also known as a kiln.
Fuse - To join together as in ceramic slip firing of glazeware. Bronze or plaster pieces that cannot be cast in a single piece are fused in sections to make the total casting complete.
Hacksaw - A thin-blade, hand-held saw for cutting small thin pieces of material.
Hammer - A percussion instrument of soft iron or steel used in sculpture. Designed for use on stone so the impact will not injure the stone.
Handles - Attachments to tools providing a working hand hold and securing hammer heads, wire ends, or wood carving tool blades.
Hand Made Tools - Custom designed modeling or carving tools shaped or fashioned by craftsmen by hand rather than by machine.
Handpiece - In electric or pneumatic usage, the piece of machinery that holds the working blade or tool.
Hard Edge - The tip of a tool or wire that has been hardened or tempered to perform a specific cutting job. Wood carving and stone carving tools have different hardnesses depending on their use.
Hardwood - Wood that has sure hardness greater than that of normal base woods. Lignum Vitae, Purple Heart, acacia and boxwood are hardwoods, whereas walnut, birch, oak, and mahogany are considered base woods.
Heartwood - The center piece of a log.
Heat Treating - A bath or chemical process used to harden steel, such as a salt bath or electrical induction.
Hercules Stand - Trade name of Sculpture House, Inc. A heavy duty sculpture stand raised and lowered by cranking. Made in the United States, it is the largest stand of its type and can hold up to 750 pounds of working material.
Hollow Casting - Thin layers of casting material built up on the inside of the mold to make a hollow rather than solid casting, in bronze created by the wax thickness but with plaster casting the interior walls are built up to form this hollow casting. Plaster can also be cast solid.
Honing - Razor sharp finishing done by hand or machine as an extra step in the sharpening process. Tools that have been honed are usually covered with a protective plastic that can be removed by striking the edge on wood.
Hook Knife - A knife with a curved cutting edge and severe hook on the tip end. Used to clean horses’ hooves in Austria and Germany, but also used in wood carving.Igneous Rock - Formed by solidification of molten magma, volcanic rock.
Igniter - Device used to start a kiln (wood or gas) torch.
Impregnated Plaster Gauze - Also known as Paris craft, trade name of Johnson & Johnson, Co.; discontinued since the mid 1980’s. Gauze strips impregnated with plaster which when soaked in water, become active and malleable. When set they form a strong hard plaster piece. Also used in the medical profession for plaster casts.
Ingot - Molded block of solid material (lead, bronze, silver, etc.) so fashioned for storage purposes.
Inlay - To rub, beat, or fuse into an incision in wood, metal, or stone.
Insulating Brick - Material made of fired clay, used for walls of an electric or gas fired kiln.
In The Round - Three-dimensional piece of sculpture, generally of stone or wood.
Investment - In bronze casting, an outer layer, slurry, or coating that can withstand the heat of the bronze after the wax model has been melted away.
Iron Oxide - Any of several oxides of iron, used in the ceramic field for glazes.
Italian Tools - The finest tools available, although high in price, have been made by hand for centuries by Italian craftsmen, for example, a hand-made rasp where the teeth are punched in one at a time.
Jasperware - Colored stoneware with white raised decorations.
Jig - Device that forms the same shape repeatedly by the use of a die or forming mechanism.
Jigger - A revolving mold on which ceramics are made.
Jolly King - Trade name of Sculpture House, Inc., an oil-base school grade modeling clay that does not contain sulfur.
Junior Power Arm - Bench or table top holding device that secures a piece of sculpture so it can be rotated to various angles. Usually used in wood working.
Kaolin - White clay used in pottery and ceramics as a filler or extender.
Kerf - A width or cut made by a cutting saw or torch.
Key, Key Groove - A square or circular indentation made in or on a mold wall to prevent the halves from shifting while casts are being poured.
Kick Wheel - Potter’s wheel turned manually by kicking with the foot. The base of the wheel or flywheel is formed of cement bricks or heavy metal.
Kiln - Gas, electric, or wood burning oven or chamber that can be heated to extremely high temperatures for glazing and firing ceramics or pottery.
Kiln Furniture - Shelves, posts, stilts, and holding devices for pottery and ceramic pieces, used in the firing process of a kiln.
Kiln Wash - Used on the interior walls of a kiln so glazes and clay will not adhere to its shelves or walls. It is a dry material, not meant to wash the kiln.
Kits, Sculpture - Sets of primary tools designed for specific uses in various sculpture fields such as ceramics, wood, stone, and wax.
Knife Rasp - Tooth rasp rounded on one end and shaped like a knife blade on the other, specifically designed and produced for wood and stone sculpture.
Latex - A natural rubber extracted from rubber trees and processed and vulcanized into a paintable liquid; used in mold making.
Lead - Heavy soft malleable ductile metal used in low temperature casting.
Leather Hard - The first stage in drying pottery or ceramics where the outer skin becomes tough but not hard. At this stage, the piece is trimmed or footed before bisque firing.
Leather Tip - Handle of a wood carving tool made of leather to soften the impact of the blow of the carving mallet.
Lignum Vitae - Hardwood from Haiti used to make carving mallets of heavy weight and long durability. Dark outer and light inner characteristics. Availability is like “the fish catch of the day in the Sahara.”
Lime - Calcium oxide used with plaster in building materials for strength.
Limestone - Formed by accumulation of organic remains - generally shells and coral. A coarse stone used for carving.
Lithium - The lightest metal known of the alkali group. Sometimes used for casting but its cost is limiting.
Long Bent Tools - Wood carving tools with a long sweeping curved shape that cuts deeply into wood, available in many shapes and sweeps.
Loop Tools - For work in ceramics, tools with heavy wire ends used to cut or trim leather- hard pottery. Available in triangular, square, or snub nose shapes according to function.
Lost Wax - Process in casting where the model is converted into wax and then melted from the mold in which bronze or other casting material will be cast.
Luster - Glow of reflected light or sheen from a type of glaze used in ceramics or pottery decoration.
Luting - Packing a joint or coating a porous surface to make it impervious to liquid.
Majolica - Earthenware covered with a thin opaque glaze for a special effect.
Male - Protruding or positive side of a mold or die.
Malleable - Able to be shaped with mallet or by hand.
Mallet - A striking tool with a rounded head, usually made of wood. Used in wood carving, as opposed to a hammer which is made of metal and is used in stone carving.
Marble - Crystallized calcium carbonate from limestone formed under extreme pressure.
Master Model - In sculpture the original model which has been cast and set aside after producing a mold from which casts are drawn. As the mold deteriorates another mold is made from the master mold and casting continues.
Maturing - Occurs when molecules in a formula have migrated over a period of time to give the optimum performance from the combination of ingredients.
Melting Point - Temperature at which a metal or material will melt.
Metamorphic Rock - Rock with a crystalline content produced by high degrees of heat and pressure.
Microcrystalline Wax - A nut brown wax derived from crude oil; soft medium hardness modeling material also known as Victory Brown wax. Extensively used in casting bronze. Also known as Micro Wax.
Minarettes - Trade name of Sculpture House, Inc. A series of small steel metal tools used for fine detail work in wax, plaster, plastilina, and clay. Available in various shapes, they are hand ground and forged.
Miniature Tools - Small stone carving tools designed for detail work and finishing. Made of high carbon steel tempered for hard stone.
Mixing Bowls - In sculpture flexible containers made of rubber ranging in capacity from 3 ounces to 5 gallons. Used in mixing plaster or slurry for mold making and casting. Dried plaster will not adhere to the rubber and its flexibility makes the plaster easy to remove. The smaller diameter size is most commonly used for repair work, while the larger size is for batch mixing for casting.
Model - The original sculpture or human model used in making a sculpture. Arguments have raged for years whether or not the actual sculpture, the first cast, or the master is considered the original.
Mold - Hollow cavity produced around a subject for use in creating duplicates of that subject in plaster, bronze, cast stone, etc. The mold is considered the negative and produces a positive cast.
Mold Knives - Heavy steel high carbon knives with four or six inch blades used to remove mold sections, to cut rubber, and to clean mold walls. Handles are made of wood and the blade is continuous through the handle for strength.
Mold Lotion - Liquid separating agent facilitating the easy removal of a cast or separation of the mold from the model.
Mold Making - Constructing a covering, shell, or coating, in single or multiple pieces, from which reproductions of the original can be made.
Mold Rubber - Natural or synthetic rubber used in the mold making process to repro- duce multiple, inexpensive, long lasting casts.
Molten - Liquid state gained from heating a metal so it can be poured.
Monochrome - Picture with a single hue.
Monumental - Larger than life, normally applied to sculptures over 8 feet high.
Mother Mold - Outer casing or securing mold to hold rubber to its natural shape when a cast is being poured. Without the mother mold elasticity of the rubber can distort dimensions of the cast.
Mottling - Having spots or blotches on the surface.
Moulage - Trade name of Douglas & Sturgess. Reusable flexible mold rubber derived from alginate. Used in mold making of the human body and delicate pieces. Moulage can be reused, up to one hundred times without adverse effect, by heating it and adding water.
Negative Space - Areas not used properly resulting in loss of that space, such as air bubbles in bronze and plaster casting.
Nichrome - Metal that can withstand high degrees of heat. Wire used in firing ceramic beads.
Nickel - Metal used extensively in alloys as a catalyst.
Nonferrous - Containing no iron.
Notches - Used in the side walls of a plaster mold to prevent shifting when casting is poured.
Noxious - Harmful to humans.
Ochre - Yellow iron used as a pigment in clays and glazes.
Octagon Handle - Wood handle with 8 sides used for wood carving tools and rasps. The handle’s shape gives the user a good grip.
Opacity - State of a substance impervious to rays of light.
Opaque Alabaster - Medium hard grade carving stone, indigenous to Italy and the western United States, through which light cannot pass.
Organic Forms - Containing carbon.
Organic Materials - Materials produced without chemical aid.
Original - First model or cast produced by a sculptor.
Oversized Handle - Large, normally round, handle used for wood carving with the larger sweep tools, generally over 2 inches in diameter.
Oxblood - Reddish medium brown color used as a pigment for glazes.
Oxidation - Color change in metals due to exposure to oxygen; forms a patina or coloration on bronze statues.
Oxide - A binary compound of oxygen with another element.
Ozark Stone - An extremely fine grain sharpening stone from the southern region of the United States used to sharpen wood and stone carving tools.
Pantograph - Machine used in enlarging and reducing sculpture; also known as a pointing machine.
Parting Agent - Spray liquid or paste that assists in the separation of the model from the mold or the cast from the mold.
Parting Tool - A “v” shaped wood or stone carving tool, also referred to as a veiner. Comes in different sizes with varying angles or degrees of slope.
Patina - Coloring of a sculpture in plaster, bronze, plastic, etc. with acids or pigments. Variations are countless due to the variety of color mixes. The natural bronze patina on statues is caused by oxidation and the weather.
Peeling - Occurs when the glaze does not adhere to the clay after firing. Caused by the mismatch of the clay body and glaze formula.
Percussion - Striking or hitting a stone or wood carving tool with force to make it function.
Permeable - A state such that water or moisture can pass through. A clay body is water permeable when it has not vitrified and water leaks through the piece.
pH - Used to express acidity and alkalinity on a scale from 0 to 14, 7 being neutral.
Pick - A pointed dual-sided stone carving tool used to reduce a basic geometric stone form rapidly; usually has a long handle ranging from 10 inches to 12 inches in length. Also called bush and pick.
Pickling - A cleaning process for bronze and other metals.
Piece Mold - Mold made of multiple sections for ease of construction. Generally used when severe undercuts are present.
Pietrasanta - Small town in northwestern Italy renowned for its sculpture studios and bronze foundries.
Pig - Solid volume of raw material in bulk, facilitating storage by foundries. For example, pigs of bronze.
Pin Holes - Small holes formed on a glazed piece in firing caused by incompatibility of the clay and glaze or by the firing temperature being too low. May also occur when mixing chemically activated, multiple-part rubbers.
Pink Alabaster - Common to the western United States, a light pink medium hard grade stone with minor to medium veining. Sometimes with a crystalline structure and often with iron deposits or fragmentation from dirt.
Pins - Metal or wood dowels that secure a sculpture to the base or pedestal, or hold sections of the sculpture together.
Plasteline - Generic name for oil and wax based modeling clay. See Plastilina.
Plaster of Paris - A generic term for industrial grade plaster or gypsum found in hardware stores. Not recommended for mold making, casting or sculpture, because of its softness and porosity.
Plaster Rasps - Specially designed rasps used for plaster work in sculpture. They are designed to look like a cheese grater so that dried plaster can be removed without clogging the tool.
Plaster Scrapers - Tools for plaster work specially designed to work against heavy resistance in the material. Made of high carbon steel, sometimes with wood handles.
Plaster Tools - Steel tools used in working plaster. They have flexible ends so they can flow with the material when wet.
Plasticine - Generic name for oil and wax base modeling clay. See Plastilina.
Plasticity - Resistance and smoothness of a clay body.
Plasticium - Generic name for oil and wax base modeling clay. See Plastilina.
Plastic Tools - Low cost injection-molded tools in the primary modeling shapes.
Plastilina - An oil- and wax-base non-hardening modeling material. Comes in two primary grades, professional and school. The professional grade becomes more pliable with age and is sought after by professional sculptors especially after it has been used for 20+ years. Estates have auctioned quantities of old plastilina at five times its original purchase price. Used material is refurbished by adding oil, wax, and at times clay binders. The professional grade material often contains sulfur which inhibits certain mold making materials, but causes the high quality effect. All pieces created with this material must be cast.
Pliatex - Trade name of Sculpture House, Inc. Used in mold making and with casting materials such as Pliatex Mold Rubber and Pliatex Casting Rubber.
lug - Created on the top or sides of a mold for a pouring and for material removal access in the mold making process of larger pieces.
Pneumatic - Operated with air. Pneumatic handpieces are used in sculpture as are rotary sanders that run on forced air from a compressor.
Point - Sharp stone carving tool for quick reduction of mass material from its bulk geometric form. Sizes vary in diameter from 3/8 inch, ½ inch, and larger.
Pointing Machine - Used in duplicating a sculpture or in enlarging and reducing pieces.
Polishing - The final process, if desired, in finishing a piece of sculpture.
Polychrome - Colorful decorations on pottery created with stains or glazes.
Polymer - A chemical compound made up of repeating structural units.
Polymer Clay - Plastic modeling material that is moist when modeled and can be fired in the kitchen oven to cure and become permanent.
Polysulfide - A compound that contains sulfur atoms.
Polyurethane - Various polymers used in mold making for flexibility and as an elastomer. May also be a type of casting resin.
Pooled Glaze - Caused by a build up of glaze (an excess of liquid on ceramics or pottery) which melts when fired and pools in a settling area.
Pooling - Caused by too great a build up of glaze.
Porcelain - A fine grolegg clay formula which produces an off-white translucent fired clay at high temperatures. The finest ceramic pieces and most difficult to achieve are made of porcelain. Material may be wheel thrown or slip cast.
Porosity - The percentage of moisture absorption capability contained in a material. Term is used in ceramics and plaster working.
Porous - The ability to absorb liquid or moisture.
Portuguese Marble - A lightly veined pink marble with slight fractures and markings, with a high crystalline structure.
Posts - Devices used in kilns to hold shelves when bisque or glaze firing.
Potash - Potassium carbonate from wood ash used in pottery and ceramic glazes.
Potter - A person who makes pottery either by hand or on a kick or electric wheel.
Potter’s Wheel - A wheel, either electric or foot-powered, that enables a potter to produce pottery using a flat level rotating disc head on a circular pipe device.
Pouring - The process by which a cast is made in a mold, either hollow or solid, in plastic, bronze, or plaster, etc.
Pouring Gate - An extended section at the top of the mold that enables liquid to be poured easily into the mold without losing material.
Pressing - Laying clay in a mold to gain a positive by applying pressure and to achieve details of the mold.
Proportional Caliper - Hand held device used to calibrate exactness for enlarging and reducing sculpture. Sizes vary from 18 to 42 inches.
Puddle - Also known as pooling, a build-up of glaze due to its over-application on a ceramic or pottery piece.
Pug Mill - Mixing machine used in pottery to mix and extrude a clay formula from either dry or moist materials.
Pulverizing - Grinding a material to a given screen mesh or fineness. See Grog.
Pumice - A powder that is mixed with water for use in a last abrasive polishing.
Pumicite - A gritty volcanic ash.
Pure Beeswax - Wax extracted from bee hives. It is used to dress wood sculpture, tie dye clothes, and seal wood. Sometimes used as a direct modeling material, but because of its high cost, not often.
Pure Metal - A single non-bonding metal, without alloys.
PVA-Polyvinyl Acetate - Plastic casting resin.
PVA-Polyvinyl Alcohol - Polymerized vinyl compound condensed into a liquid state.
Pyrometer - Device that measures the temperature in a kiln for ceramic and pottery firing.
Quarry - Site where stone is gathered. Stone suitable for carving is found in specific sites in Italy, Western United States, Vermont, etc.
Quench - To cool metal by submersion in oil or water. Term used in the tempering and heat treating process to harden steel tools.
Rack - A drying device or structure for clay pieces not yet fired that allows them to dry with the least amount of distortion.
Raku - Method of firing a special Raku clay body for a desired effect.
Rasp - Hand tool with teeth rather than serrations, used for wood, stone, plaster, or metal. It can be double-ended or single ended with the opposite end attached to a handle. Teeth are hand punched and sharp. Size and coarseness of the teeth vary.
Raw Glaze - Glaze formula component without additives. These are the primary glaze ingredients such as iron oxide, ochre, etc.
Reducing - Taking a large sculpture and making it smaller using a pantograph or reversing the enlarging process.
Reducing Agent - An additive that cuts or thins a base material. For example, shellac is cut by alcohol before applying to a model in mold making.
Reduction Firing - Firing process whereby oxygen is regulated to create a special effect on the fired clay or glaze.
Refractory - Material fired to a high enough level to withstand the high temperatures of firing in a kiln used for shelves and posts.
Regulator - Device that controls the flow of a material into a mold.
Reinforcement - Addition of metal or wood cross sections either on the outside of a mold or in the casting of delicate pieces where extra strength is required.
Relief - Flat one-sided sculpture, also called bas-relief.
Resin - Plastic liquid material designed for casting into specially constructed rubber that can withstand the heat of the curing process.
Respirator - Safety device worn over the nose and mouth to protect the lungs from harmful dust or vapors. Available in a variety of materials and designs.
Retaining Wall - Fence that separates sections of the mold; outside area on a relief mold that restrains mold making material to a given area. Constructed of various materials such as wood, metal, clay, or plastilina.
Rib - Tool used primarily by potters for shaping wet clay that has been thrown on the wheel. Can also be used for leveling or scraping.
Riffler - Small rasp type tool with fine serrated cutting edges used for finishing stone and wood. Also known as a jeweler’s rasp.
Rod - Used to strengthen internal sections of a cast. The rod should be non-corrosive so rust will not bleed through the final casting.
ROMA - Trade name of Sculpture House, Inc. Italian formula plastilina made in the United States using the highest grade materials available. Oil- and wax-base modeling material preferred by professional sculptors.
Roman Joint - Square locking section on a model or mold to keep it from shifting. Used by professional mold makers and casters, it is the most difficult joint to make.
Roman Wax - Hard casting wax used for the investment process in the lost wax casting process. Color may vary from purple to black but its brittleness will remain the same. Usually used for fine detailing before casting rather than for direct modeling.
Roughing Out - Creating the basic geometric form from a large natural piece of wood or stone; also applied to clay and plastilina.
Rondel - Round cape-shaped stone carving tool.
Royal Porcelain - Trade name of Sculpture House, Inc. Porcelain clay formula containing English China clay made exclusively in the United States. Clay is fired at cone 10-12 and produces a translucent effect. It is the most difficult clay material to throw or fire due to its delicate nature.
Running - A build-up of glaze that flows beyond desired boundaries. Also known as pooling.
Running Plaster - Liquid plaster poured before the material sets.
Rust - Reddish coating formed on metal that contains iron, caused by moisture. Rods that are galvanized, when inserted into a cast will sometimes rust through the cast plaster piece.
Rutile - Brown, deep red, or black mineral that gives a brilliant metallic luster to ceramics and pottery when fired in a glaze.
Sager - Box made of fire clay where ceramic pieces are fired. A type of fire clay used in producing high fire pottery.
Salt Bath - A procedure in which steel is heated and treated to harden or temper it.
Salt Firing - Process wherein salt is added when firing pottery to create an unusual effect. The salt is added during the glaze firing.
Salt Glaze - Glaze containing amounts of salt to produce a unique effect when fired.
Sand - Granular material caused by disintegration of rock particles; smaller than gravel but larger than silt. Used in clay bodies for strength and texture.
Sand Bag - Canvas bag filled with sand used to hold stone or wood in place when carving it. Sizes vary with the manufacturer. The bags are secured with Velcro or string. The bags are sold empty.
Sand Blasting - Process to clean stone and bronze using high pressure forced air and fine particles of sand.
Sand Casting - One of the older and more difficult methods of making waxes for bronze casting. Specially designed sand is used to pack the model before the waxes form and the pieces go to the foundry.
Sandstone - Sedimentary rock of quartz sand bound by silica or calcium carbonate. Used for buildings and stone sculpture.
Sapwood - Green wood that still contains its original sap.
Scabbing - Occurs when flakes or small pieces of metal fall from an original cast or metal sculpture.
Scrape - To remove material with a sharp edge, either a wire tool or a rectangular steel scraper.
Scrapers - Heavy duty steel tools used to remove rough resistant material such as plaster when working directly or after casting.
Screen - To sieve or run through a mesh to isolate larger particles or to remove unwanted materials from a formula.
Sculptor - A person who creates sculpture.
Sculptor, Academic - A sculptor who is associated with a school, university or academy, who has knowledge based on formal study.
Sculpture - An object created by a sculptor.
Seam Line - The line where the mold sections join and through which casting material escapes; this line occurs in all types of casting, ceramic, bronze, plaster, etc. and must be removed before firing or finishing.
Sedimentary Rock - A form of organic rock.
Set - The initial hardening of plastilina after mixing and extruding. This hardening must be removed by a second or third mixing prior to packaging.
Setting - The time required for plaster or resin to become solid, but not necessarily cured.
Settling - Occurs when particles added to a liquid drop to the bottom of a container. Plaster sprinkled over water should be left to settle on the bottom of the container to absorb water.
Sgraffito - Design made in ceramic ware or pottery with specialty tools.
Shank Ring - End of a tool used in wood carving or stone carving, where the tang in front of the blade acts as a stopper when attached to the handle.
Shard - Piece or section of broken pottery, term applied especially to fragments found in archeological digs.
Shell - The outer coating of hard set plaster of a mold. In bronze casting, a ceramic shell into which molten bronze can be poured without damage. Also known as the mother mold.
Shellac - Coating material used in mold making and casting when modeling material containing sulfur is used. Also used in mold making as a sealer.
Shelves - Ceramic furniture that holds pottery and ceramics when fired; can withstand the high temperatures of the kiln.
Shim - A separating device to divide sections on a model when the mold is to be made. May be brass, wood, tin, aluminum, clay, or plastilina.
Shivering - An effect of glaze on pottery fired at high temperatures; gives an uneven look.
Shore Hardness - Rigidity, flexibility, or hardness of a rubber used in mold making.
Short - Clay or plastilina that is dry and cracks easily when worked, a condition caused by mixing improper proportions of liquid to dry material in the formula.
Short Bent - Wood carving tool with a curved cutting edge like a “u” in the tip of the tool; creates deep quick cuts in wood.
Shrinkage - The percentage a material contracts at different stages of firing. Ceramic clays may shrink up to 20% from the original to the final fired glaze piece.
Silica - Impure forms of salt that generally occur in crystalline stone. Pulverized, it is a bonding agent in ceramic and pottery clay bodies.
Silicone - Rubber from silicone base material and elastomers used in the production of molds to cast polymers or resins. These molds can withstand the heat of the casting materials when they are mixed and poured creating high temperatures due to their natural reaction .
Single Wire End - A modeling tool with only one cutting end; the opposing end acts as an extension of the fingers in modeling.
Sinter - To cause to fuse together with heat, but without melting.
Size - Glutinous material used to fill pores and as a sealer prior to applying gold leaf.
Sketch - Rough design or model of a sculpture used as a guide to create the final work.
Skew - Diagonally cut carving tool for wood with a 45° angle for cross cutting. Sizes vary from 1/8 to 3 inches.
Skimmer - Professional scoop or spoon used to remove air bubbles from the surface of a mixed solution, such as plaster, before casting.
Skin - Thin covering over latex rubber at the initial setting.
Slag - The refuse of metals or ores.
Slake - To treat with water, as in slaking plaster before casting.
Slip - A liquid clay used in casting ceramic pieces before firing. Usually suspended with a binder to facilitate setting.
Slip Casting - Process in which slip is poured into a mold and left to set to form a layer that can be removed and fired.
Slurry - A liquid composition used in ceramic shell casting. The wax is coated with the material before being burned out so the bronze can be cast.
Smooth-On - Trade name of Smooth-On. A white polyurethane two-part mold rubber chemically activated for use in hollow cavity molds. May be thixotropic.
Soapstone - The softest carving stone, also known as talc block or ore. Available mostly in green and black. Also known as serpentine, Eskimo stone, and steatite.
Soapstone, Black - Extremely hard talc base stone indigenous to Virginia; polishes to a deep black color.
Soda Ash - Sodium carbonate used in ceramic glazes.
Sodium Chloride - Salt.
Solder - A fusing alloy of lead and tin used to join metal.
Soldering - Joining sections together with a soldering gun or by welding with a torch. To attach sections of a sculpture after they have been cast; to rejoin.
Spatula - Flexible oval or round steel tool varying in size, used to smooth models or casts and interior mold wall sections.
Spodumene - Emerald green monoclinic mineral used in ceramic glaze.
Sponge - Natural or synthetic absorbent material used for smoothing and water absorption in pottery and ceramics.
Spraying - Using an air powered tool to coat pottery with glaze or spray rubber in mold making.
Springwood - Soft porous section of wood that develops early in the growing season on the annual ring.
Spur - Hole through which liquid enters the major cavity of a mold when poured into a gate.
Stacking - Process of loading a kiln for firing, placing ceramic ware so it is not inadvertently affected by other pieces.
Stain - Used in ceramics and pottery to give a dull or matte effect in firing. Also used in patination applications as a base coloring.
Steatite - Harder form of soapstone but with the same talc base.
Steel - Iron alloyed with carbon. Creates a hard cutting material with hardness determined by the carbon content; 1095C high carbon steel is used for stone and wood carving tools.
Steel Tools - Sculptors’ tools made of high quality steel shaped and formed for specific uses in working with plaster, wax , and clay.
Steel Wool - Various grades of fine to coarse soft steel shavings used in smoothing and finishing wood, stone, and bronze sculpture.
Stilts - Steel- or ceramic-pronged holding devices used to support glazed pottery when being fired to prevent the glaze from sticking to the shelves.
Stone, Carborundum - A polishing or finishing material made of Carborundum.
Stone Carving - Shaping a stone into a piece of sculpture either by hand or with pneumatic tools.
Stone Carving Stand - Heavy duty wood stand used to support large pieces of stone for carving, usually with a concave resting area on which the stone can be rotated.
Stoneware - Ceramic clay fired to high temperatures and becoming non-porous; a harder material than the earthenware clay bodies due to the fermentation and sedimentation of its base ingredients.
Stop Cut - A cross section cut in wood and stone perpendicular to the grain or a cut that stops the normal progression of removal of wood in a specified area.
Straight Gouge - Wood or stone carving tool with a straight flat edge, stone carving tool most likely beveled.
Stratification - Forming layers in casting, generally caused by pouring non-continuously so the levels cool at different times.
Streaking - Heavy or off-balance coloration in a material, patina, or cast caused when the ingredients have not been properly mixed.
Strike - To hit with a hammer or mallet to remove material from a given area.
Studio - Where amateur or professional sculptors work. Also known as an atelier, from the French.
Stun - Shock treatment, as in dipping hot metal in oil or water in heat treating and tempering.
Styrofoam - Polystyrene plastic of different densities used for casting and direct modeling because of its light weight.
Summerwood - Heavier, less porous part of the annual ring of wood formed during the summer months.
Sweep - The curvature or angle of the cutting edge of a tool.
Symposium, Sculpture - Meeting of sculptors, teachers, and students to discuss and demonstrate sculpture techniques. Johnson Atelier regularly sponsors such events.
Synthetic Beeswax - Artificial wax made with oil, with the characteristics of natural beeswax, and costing far less.
Tacky - Not yet dry or set. A sticky state of rubber before setting or curing.
Talc - Magnesium silicate used in various ceramic and pottery formulas as a binder for plasticity. The base of soapstone ore used in carving. The base ingredient of baby powder.
Tap Drill - Tool used to make an initial hole or indentation; used in mold making or wood sculpture.
Tare Scale - Scale used to determine tare, the weight of a material found by deducting the weight of the container holding the material from the total weight. Used with polyurethane rubber mixes.
Temper - Hardness of steel when the molecular structure has been altered by heat.
Temperature - Degree of heat an object or container can withstand, as the temperature of a kiln for firing pottery or rubber for casting resin.
Tempering - Process in which steel carving tools are hardened. Under heating treatment, the molecules merge to form a hard material.
Template - Device that copies an original, used as a master form.
Tensile Strength - Strength of an object beyond which applied pressure will cause it to break. Hardness of fired clay and cast plaster objects.
Terra Cotta - An orange red color in sculpture; a red clay with grog or a base color for patina.
Texture - Visual or tactile surface of a body or substance; the feel of a certain material. One textures sculpture in a cutting fashion.
Thermal Shock - Stress or reaction caused by heating. May affect clay when firing or steel carving tools when being tempered.
Thermocouple - Used in a kiln to measure the temperature of the interior so one can adjust it as required.
Thinning - Diluting a base component part by mixing with a reducing agent, as shellac mixed with alcohol.
Throwing - Producing pottery on a potter’s wheel (electric or kick wheel) by centering and forcing the clay to take a desired shape as the wheel turns.
Tin - Low melting alloy that is malleable at ordinary temperatures. Used as a component with bronze and lead. Used as a filler and bonding agent.
Tin Oxide - Powder polishing compound that creates a deep luster finish.
Titanium - A strong metallic element used as a binder in refractory materials such as in kiln shelves and posts.
Tongs - Tool used to securely hold a material or ceramic piece while working on it when hand holding it is not feasible.
Tooth - That part of a stone carving tool that cuts a small section; also known as the cutting part on a rack or claw chisel.
Torch - Flame producing device used in wax working and bronze casting; its fuel base is alcohol or propane.
Trailing - Adding a layer or coating of slip or glaze over a ceramic or pottery piece for decorative purposes.
Translucent - Able to transmit light, as in translucent alabaster, a carving stone.
Trimming - Cutting clay away from a piece of pottery or from a footing on a bowl in the leather-hard stage before firing and glazing.
Trimming Tools - Tools designed for trimming pottery.
Triple Beam Balance - Scale used in measuring gram amounts of chemicals and glaze materials for formulas. Most accurate commercial scale used in ceramics.
Tulons - Trade name of Sculpture House, Inc. Wooden tools for burnishing and shaping clay.
Tungsten Carbide - High melting ductile metal used in hardening steel.
Turnette - Small round turntable for working with smaller ceramic objects and sculpture.
Turning - Process by which a piece of wood is shaped on an electric lathe.
Turning Tool - Long-handled high carbon steel wood working tool used to reduce wood forms to the desired effect on a lathe.
Turntable - Platform, generally round, made of wood or metal that turns as one decorates pottery or ceramics. Larger tables on ball bearings are used for large pieces of sculpture.
Umber - Brown earthen mineral used in coloring glaze and clay in ceramics and pottery.
Undercut - An overhang or protrusion of a relatively smooth plane that hinders removal of the mold. Undercuts must be worked around when mold making and casting.
Urethane - Ethyl ester of carbonic acid used as a solvent in an anti-plastic agent. Used in molds and casting material.
“V” Tool - Parting or veining tool used in wood working at 45º and 60º angles for furrowing in wood and stone.
Vacuum - State resulting from the removal of air from rubber or clay before use to avoid air bubbles in the final piece.
Vanadium - Polyvalent metallic used as an alloy as in vanadium steel.
Vapor - Gaseous state as opposed to a solid or liquid state.
Variation - The extent to which items or masses may differ. Raw materials used in formulas, for instance, may vary in quality from year to year depending on the mining level.
Vatican Art Casting Stone - Trade name of Sculpture House, Inc. Artificial casting stone made of gypsum and aggregate to simulate marble. Available in different base colors.
Vent - A channel or opening in a mold through which air and gases may escape thereby preventing damage to the cast or air pockets in the cast.
Vermiculite - A moisture absorbing silicate used as a filler in clay bodies.
Vermont Marble - A hard, white, vein-free marble from Vermont; Barry, Vermont is its center of production.
Vibration - When pouring rubber or plaster, a process of shaking the mold or container to eliminate air bubbles in the rubber or plaster.
Victory Wax - Soft brown wax or Microcrystalline Wax used in bronze casting and direct modeling. Derivative of petroleum.
Viscosity - The rate of flow at which a liquid follows a given path. In sculpture, applied to molten bronze, plaster and other metals able to be cast.
Vise - Gripping device with jaws to secure a piece of sculpture or wood that is being worked.
Vitrification - The process by which a clay body is heated until it becomes non-porous.
Volatilize - To cause to pass off in vapor.
Volcanic Ash - Produced by volcanic eruption, a material used in ceramic glaze formulas.
Volume - Amount of space occupied by a model measured in cubic units.
Warping - Distortion caused by moisture or lack of moisture in wood, and by overfiring in ceramics.
Water Glass - Silicate of sodium and water, used as a protective coating.
Wax - Substance derived from petrolatum refined to be soft, pliable, used for modeling and casting.
Wax, Positive - Wax cast from the mold that will be invested or coated with slurry then melted out. A bronze cast will result when molten bronze is poured into the cavity.
Wax Resist - In pottery and ceramics, the wax coating applied to the interior of kiln walls so glaze will not adhere to the walls in firing.
Wax Tools - Steel tools designed and produced for working with wax. They absorb heat and are especially shaped for their functions.
Weathering - Process of aging outdoors resulting in various colors or patina. Effects will differ depending on geography and climate.
Wedges - Triangular shaped wooden pegs that help secure the tightening of mold straps when casting large pieces.
Wedging - Cutting or rolling a clay body to force out internal air which can cause an explosion or damage when the clay is fired.
Wedging Board - Plaster based slab with a wire cutting device at a 45° angle for cutting pieces of clay to be wedged. May also be made without the cutting wire.
Weld - To bring separate parts together, as in jointing plaster, wax, clay, or bronze sections to form a completed piece.
White Lead - Highly toxic powder or paste with great binding ability. Sometimes used in ceramic glazes and house paint.
White Rubber - A two-part polyurethane rubber with a catalyst setting agent used in making rubber molds.
Whittler - One who works on handheld wood pieces with a small knife.
Winterstone – A Sculpting Medium is an engineered formulation developed by Lorne P. Winters (a civil engineer turned sculptor) for direct modeling and carving of finished, permanent sculptures.
Woodcarver - Person who carves wood in three dimensions with tools and a mallet.
Woodworker - Person who works wood either by handheld or powered tools, as a cabinet maker, wood turner, etc.
Zinc - Metallic element of intermediate hardness that becomes ductile with slight heating.
Zinc Oxide - An infusible white solid used as a pigment in compounding rubber and ceramic glaze.
Zirconium - Metallic element with a high melting point and resistant to corrosion. Used in refractory shelves and posts in the ceramic industry.

Alcohol Lamp - Used to heat modeling tools for wax detailing; alcohol fueled with wick or possible spout for flame direction.
Alginate - A derivative of marine algae used in mold making and casting; used for small flat items only because of its tendency to tear or rip.
Alloy - Metal compounds fused together when molten to form bronze for casting. Different component parts will result in different types of bronze.
Almaloy Wire – Also known as aluminum wire. Pliable aluminum wire used for internal support of sculptures; in gauges ranging from 1/16 inches to 3/8 inches.
Aluminum - Malleable light silver-colored metal that resists oxidation (discoloration such as patina).
Amorphous - Having no defined shape or form such as free form sculpture.

Anatomical - Structural make-up of human or animal body parts.
Anneal - To heat and cool steel so that the metal is not brittle.
Apron - Generally cotton, duck, canvas or leather used for protection against clay, plaster and dirt in the classroom or studio.
Arch - To form or bend into a desired shape as in architecture.
Argillaceous - Containing clay or clay minerals.
Arc Welding - Molding steel or metal with electrical current.
Arkansas Stone – Sharpening stone used to hone wood and stone carving tools
Armature - An internal support to hold the outer covering of a sculpture; may be made of various materials such as wood, wax, steel, but generally almaloy or aluminum wire.
Armature Wire – See Almaloy Wire.
Art Plaster - Trade name of U.S. Gypsum Co. A gypsum material with an extremely high absorption rate primarily used in ceramic slip casting molds.
Artware - Trade name of Sculpture House Inc.; a low-fire ceramic moist clay that vitrifies at Cone 04.
Atelier - Studio or workshop, usually of an artist, derived from French.
Autoclave – Apparatus in which using superheated steam under extreme pressure for purification purposes.
Aventurine - A type of translucent quartz with traces of mica throughout.
Ball Bearing - A turntable, like a lazy Susan, with hardened steel balls, designed to allow easy movement.
Ball Clay - Base clay for earthenware ceramic clay formulas.
Ball Mill - Grinding device used to mill clay and glazes, with balls rotating in a container.
Banding Wheel - A rotary top on a post or ball bearing that allows clay or a sculpture to be easily turned for working or decorating.
Barium - Silver-white metallic element of alkaline earth; a toxic material used as a pigment or extender.
Base - Holding support for the display of a finished piece of sculpture.
Basic Carving - The primary removal of clay, wood, stone, or other sculpting material to create a basic geometric shape.
Bas Relief - A sculpture that is slightly raised with no apparent undercuts.
BAZ - Trade name of Sculpture House Inc.; basic stone carving tool set consisting of chisels and one mallet, in a canvas roll.
Beeswax - A pure yellow natural wax used to dress wood or seal stone sculpture; also used in batik.
Bench Screw - A double screw device that holds a carving block of wood secure for carving; screws into the block and into the securing device.
Bench Stone - A sharpening stone, possibly of various grits, used to sharpen and hone tools.
Bentonite - An absorbing clay used as a filler in clay bodies.
Binder - A clay or wax material that enables other materials to adhere when they normally would not.
Bisque - The first firing of a clay or ceramic piece before glazing. Typical bisque firing is Cone 04 - 06.
Black Rubber - Also known as “Tuffy,” a three-part polysulfide rubber used for professional mold making.
Blanks - In wood and stone carving, pieces of steel not yet forged.
Blistering - Term used when a glaze overheats and causes bubbles to form on the pottery.
Blocked Bust - Head and shoulder cast showing the basic geometric planes of a figure; usually made of hollow cast plaster for study.
Blocked Mask - Face mask showing the basic geometric planes of the facial structure.
Block Scraper - Rectangular steel scraping device used in leveling and cleaning molds. Length can vary; can be used with or without teeth.
Bluing - A water-soluble pigment used in the initial cast of a plaster waste mold to alert the mold maker to the closeness of the cast.
Bonded Bronze - A polymer resin mixed with bronze powder to give the feel and simulated weight of a bronze cast without the expense.
Bone China - Translucent white china made with bone ash and clay.
Bone Emulsion - Trade name of Sculpture House Inc.; a liquid which when mixed with plaster adds strength to the plaster.
Boneware - Trade name of Sculpture House Inc.; a pure self-hardening clay in red, white and gray. Used for direct modeling or in plaster press molds.
Boxwood Tool - A modeling tool formerly made of a wood named “boxwood”; in a variety of shapes and lengths, these tools today may or may not now be made of boxwood but of a similar hardwood.
Brass - Alloy consisting of copper and zinc.
Brazing - Joining of metals by use of heat.
Bronze - A combination of copper and tin; the compound may vary in proportions of each.
Bronze Rod - A bronze material used for brazing a joint or doing repair work on a bronze casting.
Bruise - Term most commonly used in stone carving. When a piece is dropped on a hard surface, discoloration or imperfection appears on the surface where the stone made contact.
Brush - A wire or bristle material used in cleaning the interior of molds and in the application of patina on a piece of sculpture.
Bubbling - Caused by the overheating or high temperature of a kiln during glaze firing of pottery.
Burl - Hard woody hemispherical outgrowth on a tree.
Burlap - An open mesh cloth used in reinforcing molds and sculptures; most commonly impregnated with plaster.
Burma Slip - Slip stone made of Burma stone used for sharpening tools.
Burner - Flame producing burning device such as an oven.
Burnout - The process in which wax is burned from a ceramic shell mold so that molten metal such as bronze may be poured.
Bush Hammer - A cross checked steel hammer used to reduce large sections of stone.
Bush Pick - Tool, one end a bush hammer and the opposite end a straight pick; the striking end comes to a point.

Cabinet Rasps - Medium coarse rasps with teeth attached to a handle of wood; used for reducing and finishing wood and stone.
Cadmium - Ductile malleable material used as a protective coating on steel rasps.
Calcium - Silver-white metallic element of alkaline earth.
Calipers - A device of wood or aluminum, generally curved, used for measuring dimensions of a piece for reproduction.
Caped Chisel - A round end stone carving tool used to make gouges or furls like a cornfield.
Carbide - Binary element of carbon with a more electropositive element; extremely hard, brittle metal.
Carbide Tools - Tools with carbide cutting edges brazed and sharpened as tips for longer lasting use without repeated sharpening.
Carburize - To combine or impregnate with carbon; a flame produces the carbon effect on metal.
Carrara - A small town in Italy where the Carrara marble quarries are found.
Carrara Marble - An Italian stone, in varying grades of color, indigenous to Carrara, Italy; used by Michelangelo
Carving - The act of shaping stone, wood, and plaster by cutting with specially designed tools.
Carving Chisel - A flat, high carbon steel tool, with a flat sharp cutting surface used with a hammer or mallet to carve stone, wood, or plaster. Sweep and width vary with size of the tool and the bevel is at different angles for wood or stone tools.
Carving Tools - Tools used in forming wood, stone, wax, plaster, or clay pieces. Can be made from high carbon steel, most commonly used in wood carving and stone carving.
Case Mold - A mold usually constructed as a retaining mold for casting slip.
Cast - A reproduction of an original piece of sculpture in any number of casting materials, most commonly plaster, plastic, or bronze.
Casting - The process that duplicates a model or piece by pouring casting material into a pre- formed mold.
Casting, Investment - Process whereby a model is covered with a ceramic shell investment for the pouring of bronze. This investment or ceramic shell can withstand the high temperature of the molten bronze, whereas other materials cannot.
Casting Plaster - A gypsum product most commonly used in casting sculpture. Produced by U.S. Gypsum Co. specifically for casting. It is unlike plaster of Paris which is a commercial more porous plaster used in plasterboard in the housing industry.
Casting Rubber - A latex rubber that is cast into a plaster mold to achieve a positive cast. Flexibility (hardness) from rubber band flexible to wood hard rigid can be increased or decreased by using a filler in proportionate amounts.
Cast Stone - A powder containing marble aggregate and several types of gypsum. When mixed properly with water and cast into a mold, it resembles Noxus marble from Greece.
Cavity, Hollow Mold - A type of mold made with a mother mold with a retaining blanket over an original model. Once removed and the outer shell mold replaced, a hollow cavity is formed where a chemically activated rubber may be poured into the resulting hollow cavity thus creating a flexible rubber mold.
Cement - A powder of alumina, silica, lime, iron oxide, and magnesia burned together and pulverized to make mortar or concrete.
Centigrade - Temperature range from 0° (freezing) to 100° (boiling). Normally used when casting bronze or polyurethane plastic where temperature will affect the mold material when cast.
Centimeter - Unit of length within the metric system.
Centrifugal - Acting away from the center forcing material outward.
Centrifugal Casting - Small sculpture or castings made with a centrifugal mold by spinning molten material.
Ceramic - A clay material such as earthenware or porcelain made of a non-metallic mineral fired at high temperature.
Ceramic Shell - A slurry coating over a wax model; in the bronze casting process the wax is burned or melted out enabling bronze to be poured, while molten, creating the bronze cast .
Ceramist - A person engaging in ceramics, either casting greenware or making pottery.
Cesta - Nylon reinforced basket or pail with double handles, made of black rubber, used in mold making and casting.
Chasing - Hammering or shaping rough areas or seam lines. Usually associated with bronze work.
Checking - Cracking caused by the absorption or evaporation of moisture in wood products.
Cherry Red - Color of metal achieved in forging or heat treating steel.
Chimney - Flue of an exhaust vent in an oven to release gas and fumes.
Chip Carving - Type of wood working done with handheld palm grip tools.
Chipping- Striking a piece of wood or stone with a tool and/or hammer causing the basic geometric form to change.
Chisel - A stone, plaster, or wood working tool with a flat straight edge. Usually beveled at 45° on one or both sides.
Chromium - Chemical used in electroplating metals.
Chuck - Area that holds the shank or end of a grinding burr or handpiece.
Claw - In stone carving, a tooth chisel.
Clay - Earthen material that is plastic when moist and hard when fired, used in pottery and ceramics.
Clay Bodies - Formulas of different base clays and binders that create moist clays in specific colors, firing ranges, and consistency. Usually developed by ceramists as private formulas.
Clay Fence - A separating line usually 1 inch high by 1/8 inch wide, used to divide a model into sections for the mold making process.
Clay Flour - Dried and refined air floated natural clay in the dry state (powder). Gathered from primary indigenous regions of the world having specific characteristics particular to earthenware, stoneware, porcelain, etc.
Claystone - Trade name of Sculpture House, Inc. Self-hardening clay with cornstarch hardener and cotton fiber filler to decrease shrinkage and cracking while drying over an armature.
Clay Wall - A separating device in mold making. See Clay Fence.
Clay Water - A thin liquid mixture of clay flour and water used as a release in casting and mold making.
Clean Clay - A soft oil-base modeling clay without sulfur.
Clean Up Tools - Different shaped scraping tools used in the removal of seam lines on slip cast pieces.
Cobalt - Greenish blue pigment used in ceramics to color glazes. Contained in silver ore.
Cold Cast - Casting done with plastic polymers or resin. Also casting done with a mixture of bronze powder to simulate bronze.
Cold Pour Rubber - A casting rubber of urethane, usually mixed in three stages using a catalyst that chemically cures rather than air cures. Also known as Black Tuffy, or Cold Pour Mold Rubber.
Collet - Device used in securing the shank of different size burrs, either increasing availability or reducing availability, as needed, to fit a handpiece shaft.
Colorado Marble - A white crystalline marble, or Yule marble, of medium hardness with very little veining, indigenous to northern Colorado.
Compound - Mixture of different materials to form a mass used in buffing or polishing. Can be different degrees of coarseness.
Cone - A triangular-shaped heat testing device used in the ceramic firing process. Cones melt at different degrees of temperature indicating the internal temperature of the kiln, and sometimes activating a shut-off device within the kiln to turn the heat off at a specific temperature to prevent over-firing the contents.
Contamination - Occurs when foreign material is introduced to a given process. For example, plaster residue in a clay ceramic piece which causes an explosion in the kiln while firing.
Copper - Reddish metallic element that is malleable, and conducts heat and electricity well.
Core - The center of the mold.
Core Pin - Device that holds the core in place while making a casting.
Cornwall Stone - A type of clay flour used in private or special clay formulas for a specific effect.
Corrosion - A natural hemispheric effect caused by water and oxygen that may result in pitting or discoloration.
Crackle - A hairline cracking or shattering effect caused by the shrinkage of glaze from pottery and ceramic pieces during firing. Generally caused by incompatibility of the clay contents.
Crawling - Occurs when glaze has been over-applied and runs in pools during the firing process. Or spider web effect or cracking caused by the improper fit of glaze to the clay. Glaze does not shrink with the clay.
Crosshatch - Scoring with perpendicular cuts in a checker board fashion, commonly used in wood working or, at times, in stone carving.
Crucible - Container used to hold molten metal for pouring or centrifugal casting.
Crystallization - The act of becoming crystalline in form
Custom Tools - Tools made to individual specifications to fit a customer’s special needs or requirements, used with stone, clay, and/or plastilina.
Damp Closet - A container used to store moist clay to preserve its pliability.
De-Air - To remove air from a moist ceramic pottery clay body with vacuum compression.
Decant - To pour from one vessel to another.
Decomposition - To separate into simpler parts.
De-gas - To remove vapor or gas from molten metal before casting.
Dehydration - The removal of bound water.
Della Robbia - Trade name of Sculpture House, Inc. A self-hardening clay that can be fired in a kitchen oven at low temperatures; for decorative use only, nonfunctional pottery.
Denatured - Term describing alcohol which is unfit for consumption due to modification by heating. Used in mold making and casting.
Density - The mass of a substance per unit volume. Usually used in determining amounts of clay required for a project or a piece. Mathematically determine the total cubic inches of the piece to be made (height times weight times depth). One ounce of material equals one cubic inch.
De-oxidation - The removal of oxygen as in reduction firing in ceramics to achieve a specific effect.
De-vitrify - To deprive of glassy luster and transparency. To change from a glassy to a crystalline condition.
De-waxing - Removing the wax model from a mold; usually accomplished with heat.
Dextrin - A sticky starch used in adhesives; also used in self-hardening clays.
Die - A device to create multiples of an original by stamping or pressing. Usually made of tool steel with a male and female half.
Dipping - The process in mold making or glazing ceramics in which a piece is submerged to give it a coating.
Dipping Tongs - In ceramics, a tool to hold pottery when dipping it into a glaze solution prior to firing.
Direct Carving - When the final piece is sculpted from an original source, usually in wood, stone, and wax carving.
Dolomite - Ceramic base material used to enhance plasticity in ceramic clay bodies.
Double Wire End - A tool made with cutting wires on each end with a wooden or metal tapered handle to secure the two working ends; used in clay modeling and plaster work.
Draft - Occurs in kiln firing to control temperature in down draft kilns.
Draw Knife - A flat or concave beveled blade with perpendicular handles so that the blade can be drawn or pulled toward the body of the user. Used in boat making and wood carving.
Dremel Tool - Trade name of Dremel Company. Electrical power tools that turn at high speed in a rotary motion, used for grinding, shaping, and finishing.
Dresden Clay - Trade name of Sculpture House, Inc. An English talc pottery clay that contains grog.
Dryness, Short - When a mixture contains too much clay flour in proportion to its liquid bonding agent, in either water-base or oil-base materials.
Ductile - Capable of being fashioned into a new form, as in aluminum wire or almaloy wire.
Duron Modeling Tools - Plastic modeling tools made by injection molding to make different shaped plastic modeling tools. Owned by Sculpture House, Inc.
Dust Mask - Face device, in styles ranging from cotton gauze to cylinder cartridge containers, to protect against inhalation of dust and fumes while mold making and casting.
Dye - A coloration used in waste mold casting to determine when the removal mold is coming close to the cast piece, thus preventing damage to the cast.
Earthenware Clay - Slightly porous clay fired at low temperatures.
Eldorado Stand - Trade name of Sculpture House, Inc. A medium strength modeling stand with gear crank raising and lowering device, three-legged, collapsible, can hold 200 pounds of working material.
Electric Wheel - Potter’s wheel run by electricity either at fixed variable speeds or with variable speed foot pedals. May be run with belts or cones; can throw up to 50 or more pounds of clay at one time. Specifications will vary with the manufacturer.
Electrode - A conductor used to establish electrical contact with a nonmetallic part or circuit.
Electrolyte - A nonmetallic electrical conductor in which current is carried by the movement of ions. Used in electroplating castings.
Enameling - Covering, inlaying, or decorating with a colorful surface by fusion of an opaque, nitrous composition to metal.
Epoxy Resin - A multiple-part casting material; when mixed with a catalyst, it becomes hard plastic.
Epsom Salt - Colorless white crystalline salt, hydrate magnesium sulfate with cathartic properties. Used with ceramic glaze and in firing techniques.
Extruding - Mixing and forming clay or plastilina into rounds or squares for storage to allow the molecular structure to migrate.
Face Shield - A clear curved plastic protection device with movable shield worn over the head to protect the face and neck from debris while carving stone or wood.
Fahrenheit - A thermometric scale. Boiling point is 212° above zero, freezing point is 32°.
Fat, Fatty - In working with clay and ceramics, indicates a texture resulting from excessive bentonite or water, making the material difficult to control.
Fat Oil - Oil derived from animals; has a high acid content.
Feldspar - Constituent of nearly all crystalline rock with aluminum silicates. Used in the ceramic field.
Female - The negative half of a mold or die.
Fettling - Shaping an object.
Fettling Knife - A tool designed to shape and texture models in sculpture and pottery.
Fiberglass - Glass in a fibrous form used in making casts that are light weight but strong.
Fifth Wheel - A heavy gauge ball bearing device from 12 to 36 inches in diameter used to hold and turn heavy pieces of sculpture; sometimes used as a table turning mechanism to rotate live models for sculpture classes. In the early 1900’s used to turn trains around to head them back in the direction from which they came.
File - Tool with cutting ridges used to shape sculptures in stone, wood, plaster and resin. These cutting edges are usually cross cut rather than punched, forming small ground cutting surfaces.
Filler - Ingredient which when added to a base material bonds or strengthens the mixture.
Fimo - A self-hardening cellulose body of light weight that dries white.
Fine Cut Rasps - Smoothing and finishing tools that have close cut surfaces for extra fine finishing in the last stages of reduction.
Finishing Material - Sanding, rasping, or buffing compounds used in the final stages of sculpture.
Firebox - Chamber that contains a heated area such as a kiln.
Fire Brick - The insulating brick or interior walls of ceramic kilns used in firing pottery.
Fire Clay - Clay that can withstand the high temperatures used in ceramics and pottery. Also used to make fire brick for the interior walls of ceramic kilns.
Firing - The process of heating ceramic clay to a temperature at which the particles merge and become hard. In glazes the dried material liquefies and becomes glasslike when cooled. With clay the material becomes non-porous in its final state, not always necessary when firing pottery.
Firing Range - The temperature that a clay can withstand without distortion or warping either in the bisque or glaze firing; generally in cone ranges 014 to 10, temperatures from 1418°F to 2345°F. The point at which vitrification occurs (merging of the molecular structure) as stated in cone number.
Firing Scale - The temperatures at which different clays can be fired, given in cone ranges.
Firmer - In wood working a type of chisel with a thin flat blade cut at an angle.
Fish Tail - A wood working tool where the sweep or cutting edge fans out on both sides, resembling a fish tail.
Fissure - Break or crack, in stone carving and sometimes in bronze casting.
Fit, Clay/Glaze - When a ceramic glaze adapts well to a certain clay body without grazing, cracking or pooling. It can be a long experimental process to find a fit, especially with special formula clays and glazes.
Fitch - Section of wood prepared to be dried prior to carving. It is usually sealed and arranged so moisture evaporates naturally to prevent checking (cracking) in the future.
Flaking - Pieces of fired glaze chipping off pottery after firing, usually caused by incompatible clay and glaze.
Flashing - A web-like residue on casting material where the seam lines meet and the casting material has escaped, common in most castings (bronze, slip, and plaster casting). The flashing is removed by cutting, scraping, and finishing.
Flash Point - The temperature at which an item or material will combust. In sculpture used when working with wax or bronze.
Flat Chisel - A tool with a straight flat cutting edge used in wood and stone carving.
Flaw - Defect in a cast or forging, (even a stone), that renders the material unusable.
Flexible Bowls - Rubber bowls of varying diameters and sizes used in mixing plaster for casting and for repair work. Casting material is easily removed by flexing the bowl.
Flexible Mold - A mold that can be removed from a cast by stretching.
Flexible Paint - Paint that expands and contracts with an elastic effect when applied to a rubber casting. Usually sprayed on a movable object where flexibility is desired.
Flexible Pallet - A thin scraping device used in mold making, casting, and ceramics to smooth the surface of wet plaster or moist clay.
Flexite Gelatin - Flexible reusable horsehide glue. Used in the production of hollow cavity molds in the early 1900’s; use of the material has been discontinued in mold making and casting.
Flint - Mass hard quartz, used as a binder in clay bodies.
Flourspar - Used as a flux in making glazes.
Fluidizing - Making flow like a liquid, as in mixing plaster or ceramic slip for casting.
Flux - A substance used to promote fusion in ceramic and welding bronze sections of a mold.
Footing - Bottom section of a piece of pottery generally raised from the base of the pot or bowl.
Foredom Tool - Trade name of Foredom Electric, Co. Electric, rotating, variable speed, heavy duty grinding machine with interchangeable handpieces. Motors are available in different R.P.M.’s and horsepower.
Forge - Oven in which tools or metal are heated making them easy to shape to specific designs. The process by which a tool for working in stone, wood, plaster or wax is heated and shaped.
Form - To shape to resemble a vision of thought or sight. Free form is an unconventional shape inspired by an inner vision.
Formula - A combination of different materials blended to achieve a desired effect in clay, wax, plastilina, and glazes.
Foundry - A studio wherein molten metal, usually bronze, is cast into sculpture.
Fracture - To break or go beyond the limits or tolerance of an object, usually occurring in bronze casting or ceramic firing. Can also be a break in a boulder to be used in stone carving.
French Clay - Known to sculptors of the early 1900’s as a fine quality smooth modeling clay for marquees or models of their sculpture. Replaced in the 1990’s by Hugo Grey Moist Clay.
Frit - A component used in making glaze and glass of varying meshes and colors.
Frosting Tool - Tool with multiple pointed cutting edges on a squared surface, somewhat like a waffle iron, mounted on a hammer type handle. It may vary in dimensions from ½ to 2 inches. Its primary use is to reduce stone for sculpture.
Fuller’s Earth - A clay that lacks plasticity, used as a filler in certain clay bodies to bind other plastic clays together.
Furnace - A chamber used to fire pottery or enamels at high temperatures. Also known as a kiln.
Fuse - To join together as in ceramic slip firing of glazeware. Bronze or plaster pieces that cannot be cast in a single piece are fused in sections to make the total casting complete.
Hacksaw - A thin-blade, hand-held saw for cutting small thin pieces of material.
Hammer - A percussion instrument of soft iron or steel used in sculpture. Designed for use on stone so the impact will not injure the stone.
Handles - Attachments to tools providing a working hand hold and securing hammer heads, wire ends, or wood carving tool blades.
Hand Made Tools - Custom designed modeling or carving tools shaped or fashioned by craftsmen by hand rather than by machine.
Handpiece - In electric or pneumatic usage, the piece of machinery that holds the working blade or tool.
Hard Edge - The tip of a tool or wire that has been hardened or tempered to perform a specific cutting job. Wood carving and stone carving tools have different hardnesses depending on their use.
Hardwood - Wood that has sure hardness greater than that of normal base woods. Lignum Vitae, Purple Heart, acacia and boxwood are hardwoods, whereas walnut, birch, oak, and mahogany are considered base woods.
Heartwood - The center piece of a log.
Heat Treating - A bath or chemical process used to harden steel, such as a salt bath or electrical induction.
Hercules Stand - Trade name of Sculpture House, Inc. A heavy duty sculpture stand raised and lowered by cranking. Made in the United States, it is the largest stand of its type and can hold up to 750 pounds of working material.
Hollow Casting - Thin layers of casting material built up on the inside of the mold to make a hollow rather than solid casting, in bronze created by the wax thickness but with plaster casting the interior walls are built up to form this hollow casting. Plaster can also be cast solid.
Honing - Razor sharp finishing done by hand or machine as an extra step in the sharpening process. Tools that have been honed are usually covered with a protective plastic that can be removed by striking the edge on wood.
Hook Knife - A knife with a curved cutting edge and severe hook on the tip end. Used to clean horses’ hooves in Austria and Germany, but also used in wood carving.Igneous Rock - Formed by solidification of molten magma, volcanic rock.
Igniter - Device used to start a kiln (wood or gas) torch.
Impregnated Plaster Gauze - Also known as Paris craft, trade name of Johnson & Johnson, Co.; discontinued since the mid 1980’s. Gauze strips impregnated with plaster which when soaked in water, become active and malleable. When set they form a strong hard plaster piece. Also used in the medical profession for plaster casts.
Ingot - Molded block of solid material (lead, bronze, silver, etc.) so fashioned for storage purposes.
Inlay - To rub, beat, or fuse into an incision in wood, metal, or stone.
Insulating Brick - Material made of fired clay, used for walls of an electric or gas fired kiln.
In The Round - Three-dimensional piece of sculpture, generally of stone or wood.
Investment - In bronze casting, an outer layer, slurry, or coating that can withstand the heat of the bronze after the wax model has been melted away.
Iron Oxide - Any of several oxides of iron, used in the ceramic field for glazes.
Italian Tools - The finest tools available, although high in price, have been made by hand for centuries by Italian craftsmen, for example, a hand-made rasp where the teeth are punched in one at a time.
Jasperware - Colored stoneware with white raised decorations.
Jig - Device that forms the same shape repeatedly by the use of a die or forming mechanism.
Jigger - A revolving mold on which ceramics are made.
Jolly King - Trade name of Sculpture House, Inc., an oil-base school grade modeling clay that does not contain sulfur.
Junior Power Arm - Bench or table top holding device that secures a piece of sculpture so it can be rotated to various angles. Usually used in wood working.
Kaolin - White clay used in pottery and ceramics as a filler or extender.
Kerf - A width or cut made by a cutting saw or torch.
Key, Key Groove - A square or circular indentation made in or on a mold wall to prevent the halves from shifting while casts are being poured.
Kick Wheel - Potter’s wheel turned manually by kicking with the foot. The base of the wheel or flywheel is formed of cement bricks or heavy metal.
Kiln - Gas, electric, or wood burning oven or chamber that can be heated to extremely high temperatures for glazing and firing ceramics or pottery.
Kiln Furniture - Shelves, posts, stilts, and holding devices for pottery and ceramic pieces, used in the firing process of a kiln.
Kiln Wash - Used on the interior walls of a kiln so glazes and clay will not adhere to its shelves or walls. It is a dry material, not meant to wash the kiln.
Kits, Sculpture - Sets of primary tools designed for specific uses in various sculpture fields such as ceramics, wood, stone, and wax.
Knife Rasp - Tooth rasp rounded on one end and shaped like a knife blade on the other, specifically designed and produced for wood and stone sculpture.
Latex - A natural rubber extracted from rubber trees and processed and vulcanized into a paintable liquid; used in mold making.
Lead - Heavy soft malleable ductile metal used in low temperature casting.
Leather Hard - The first stage in drying pottery or ceramics where the outer skin becomes tough but not hard. At this stage, the piece is trimmed or footed before bisque firing.
Leather Tip - Handle of a wood carving tool made of leather to soften the impact of the blow of the carving mallet.
Lignum Vitae - Hardwood from Haiti used to make carving mallets of heavy weight and long durability. Dark outer and light inner characteristics. Availability is like “the fish catch of the day in the Sahara.”
Lime - Calcium oxide used with plaster in building materials for strength.
Limestone - Formed by accumulation of organic remains - generally shells and coral. A coarse stone used for carving.
Lithium - The lightest metal known of the alkali group. Sometimes used for casting but its cost is limiting.
Long Bent Tools - Wood carving tools with a long sweeping curved shape that cuts deeply into wood, available in many shapes and sweeps.
Loop Tools - For work in ceramics, tools with heavy wire ends used to cut or trim leather- hard pottery. Available in triangular, square, or snub nose shapes according to function.
Lost Wax - Process in casting where the model is converted into wax and then melted from the mold in which bronze or other casting material will be cast.
Luster - Glow of reflected light or sheen from a type of glaze used in ceramics or pottery decoration.
Luting - Packing a joint or coating a porous surface to make it impervious to liquid.
Majolica - Earthenware covered with a thin opaque glaze for a special effect.
Male - Protruding or positive side of a mold or die.
Malleable - Able to be shaped with mallet or by hand.
Mallet - A striking tool with a rounded head, usually made of wood. Used in wood carving, as opposed to a hammer which is made of metal and is used in stone carving.
Marble - Crystallized calcium carbonate from limestone formed under extreme pressure.
Master Model - In sculpture the original model which has been cast and set aside after producing a mold from which casts are drawn. As the mold deteriorates another mold is made from the master mold and casting continues.
Maturing - Occurs when molecules in a formula have migrated over a period of time to give the optimum performance from the combination of ingredients.
Melting Point - Temperature at which a metal or material will melt.
Metamorphic Rock - Rock with a crystalline content produced by high degrees of heat and pressure.
Microcrystalline Wax - A nut brown wax derived from crude oil; soft medium hardness modeling material also known as Victory Brown wax. Extensively used in casting bronze. Also known as Micro Wax.
Minarettes - Trade name of Sculpture House, Inc. A series of small steel metal tools used for fine detail work in wax, plaster, plastilina, and clay. Available in various shapes, they are hand ground and forged.
Miniature Tools - Small stone carving tools designed for detail work and finishing. Made of high carbon steel tempered for hard stone.
Mixing Bowls - In sculpture flexible containers made of rubber ranging in capacity from 3 ounces to 5 gallons. Used in mixing plaster or slurry for mold making and casting. Dried plaster will not adhere to the rubber and its flexibility makes the plaster easy to remove. The smaller diameter size is most commonly used for repair work, while the larger size is for batch mixing for casting.
Model - The original sculpture or human model used in making a sculpture. Arguments have raged for years whether or not the actual sculpture, the first cast, or the master is considered the original.
Mold - Hollow cavity produced around a subject for use in creating duplicates of that subject in plaster, bronze, cast stone, etc. The mold is considered the negative and produces a positive cast.
Mold Knives - Heavy steel high carbon knives with four or six inch blades used to remove mold sections, to cut rubber, and to clean mold walls. Handles are made of wood and the blade is continuous through the handle for strength.
Mold Lotion - Liquid separating agent facilitating the easy removal of a cast or separation of the mold from the model.
Mold Making - Constructing a covering, shell, or coating, in single or multiple pieces, from which reproductions of the original can be made.
Mold Rubber - Natural or synthetic rubber used in the mold making process to repro- duce multiple, inexpensive, long lasting casts.
Molten - Liquid state gained from heating a metal so it can be poured.
Monochrome - Picture with a single hue.
Monumental - Larger than life, normally applied to sculptures over 8 feet high.
Mother Mold - Outer casing or securing mold to hold rubber to its natural shape when a cast is being poured. Without the mother mold elasticity of the rubber can distort dimensions of the cast.
Mottling - Having spots or blotches on the surface.
Moulage - Trade name of Douglas & Sturgess. Reusable flexible mold rubber derived from alginate. Used in mold making of the human body and delicate pieces. Moulage can be reused, up to one hundred times without adverse effect, by heating it and adding water.
Negative Space - Areas not used properly resulting in loss of that space, such as air bubbles in bronze and plaster casting.
Nichrome - Metal that can withstand high degrees of heat. Wire used in firing ceramic beads.
Nickel - Metal used extensively in alloys as a catalyst.
Nonferrous - Containing no iron.
Notches - Used in the side walls of a plaster mold to prevent shifting when casting is poured.
Noxious - Harmful to humans.
Ochre - Yellow iron used as a pigment in clays and glazes.
Octagon Handle - Wood handle with 8 sides used for wood carving tools and rasps. The handle’s shape gives the user a good grip.
Opacity - State of a substance impervious to rays of light.
Opaque Alabaster - Medium hard grade carving stone, indigenous to Italy and the western United States, through which light cannot pass.
Organic Forms - Containing carbon.
Organic Materials - Materials produced without chemical aid.
Original - First model or cast produced by a sculptor.
Oversized Handle - Large, normally round, handle used for wood carving with the larger sweep tools, generally over 2 inches in diameter.
Oxblood - Reddish medium brown color used as a pigment for glazes.
Oxidation - Color change in metals due to exposure to oxygen; forms a patina or coloration on bronze statues.
Oxide - A binary compound of oxygen with another element.
Ozark Stone - An extremely fine grain sharpening stone from the southern region of the United States used to sharpen wood and stone carving tools.
Pantograph - Machine used in enlarging and reducing sculpture; also known as a pointing machine.
Parting Agent - Spray liquid or paste that assists in the separation of the model from the mold or the cast from the mold.
Parting Tool - A “v” shaped wood or stone carving tool, also referred to as a veiner. Comes in different sizes with varying angles or degrees of slope.
Patina - Coloring of a sculpture in plaster, bronze, plastic, etc. with acids or pigments. Variations are countless due to the variety of color mixes. The natural bronze patina on statues is caused by oxidation and the weather.
Peeling - Occurs when the glaze does not adhere to the clay after firing. Caused by the mismatch of the clay body and glaze formula.
Percussion - Striking or hitting a stone or wood carving tool with force to make it function.
Permeable - A state such that water or moisture can pass through. A clay body is water permeable when it has not vitrified and water leaks through the piece.
pH - Used to express acidity and alkalinity on a scale from 0 to 14, 7 being neutral.
Pick - A pointed dual-sided stone carving tool used to reduce a basic geometric stone form rapidly; usually has a long handle ranging from 10 inches to 12 inches in length. Also called bush and pick.
Pickling - A cleaning process for bronze and other metals.
Piece Mold - Mold made of multiple sections for ease of construction. Generally used when severe undercuts are present.
Pietrasanta - Small town in northwestern Italy renowned for its sculpture studios and bronze foundries.
Pig - Solid volume of raw material in bulk, facilitating storage by foundries. For example, pigs of bronze.
Pin Holes - Small holes formed on a glazed piece in firing caused by incompatibility of the clay and glaze or by the firing temperature being too low. May also occur when mixing chemically activated, multiple-part rubbers.
Pink Alabaster - Common to the western United States, a light pink medium hard grade stone with minor to medium veining. Sometimes with a crystalline structure and often with iron deposits or fragmentation from dirt.
Pins - Metal or wood dowels that secure a sculpture to the base or pedestal, or hold sections of the sculpture together.
Plasteline - Generic name for oil and wax based modeling clay. See Plastilina.
Plaster of Paris - A generic term for industrial grade plaster or gypsum found in hardware stores. Not recommended for mold making, casting or sculpture, because of its softness and porosity.
Plaster Rasps - Specially designed rasps used for plaster work in sculpture. They are designed to look like a cheese grater so that dried plaster can be removed without clogging the tool.
Plaster Scrapers - Tools for plaster work specially designed to work against heavy resistance in the material. Made of high carbon steel, sometimes with wood handles.
Plaster Tools - Steel tools used in working plaster. They have flexible ends so they can flow with the material when wet.
Plasticine - Generic name for oil and wax base modeling clay. See Plastilina.
Plasticity - Resistance and smoothness of a clay body.
Plasticium - Generic name for oil and wax base modeling clay. See Plastilina.
Plastic Tools - Low cost injection-molded tools in the primary modeling shapes.
Plastilina - An oil- and wax-base non-hardening modeling material. Comes in two primary grades, professional and school. The professional grade becomes more pliable with age and is sought after by professional sculptors especially after it has been used for 20+ years. Estates have auctioned quantities of old plastilina at five times its original purchase price. Used material is refurbished by adding oil, wax, and at times clay binders. The professional grade material often contains sulfur which inhibits certain mold making materials, but causes the high quality effect. All pieces created with this material must be cast.
Pliatex - Trade name of Sculpture House, Inc. Used in mold making and with casting materials such as Pliatex Mold Rubber and Pliatex Casting Rubber.
lug - Created on the top or sides of a mold for a pouring and for material removal access in the mold making process of larger pieces.
Pneumatic - Operated with air. Pneumatic handpieces are used in sculpture as are rotary sanders that run on forced air from a compressor.
Point - Sharp stone carving tool for quick reduction of mass material from its bulk geometric form. Sizes vary in diameter from 3/8 inch, ½ inch, and larger.
Pointing Machine - Used in duplicating a sculpture or in enlarging and reducing pieces.
Polishing - The final process, if desired, in finishing a piece of sculpture.
Polychrome - Colorful decorations on pottery created with stains or glazes.
Polymer - A chemical compound made up of repeating structural units.
Polymer Clay - Plastic modeling material that is moist when modeled and can be fired in the kitchen oven to cure and become permanent.
Polysulfide - A compound that contains sulfur atoms.
Polyurethane - Various polymers used in mold making for flexibility and as an elastomer. May also be a type of casting resin.
Pooled Glaze - Caused by a build up of glaze (an excess of liquid on ceramics or pottery) which melts when fired and pools in a settling area.
Pooling - Caused by too great a build up of glaze.
Porcelain - A fine grolegg clay formula which produces an off-white translucent fired clay at high temperatures. The finest ceramic pieces and most difficult to achieve are made of porcelain. Material may be wheel thrown or slip cast.
Porosity - The percentage of moisture absorption capability contained in a material. Term is used in ceramics and plaster working.
Porous - The ability to absorb liquid or moisture.
Portuguese Marble - A lightly veined pink marble with slight fractures and markings, with a high crystalline structure.
Posts - Devices used in kilns to hold shelves when bisque or glaze firing.
Potash - Potassium carbonate from wood ash used in pottery and ceramic glazes.
Potter - A person who makes pottery either by hand or on a kick or electric wheel.
Potter’s Wheel - A wheel, either electric or foot-powered, that enables a potter to produce pottery using a flat level rotating disc head on a circular pipe device.
Pouring - The process by which a cast is made in a mold, either hollow or solid, in plastic, bronze, or plaster, etc.
Pouring Gate - An extended section at the top of the mold that enables liquid to be poured easily into the mold without losing material.
Pressing - Laying clay in a mold to gain a positive by applying pressure and to achieve details of the mold.
Proportional Caliper - Hand held device used to calibrate exactness for enlarging and reducing sculpture. Sizes vary from 18 to 42 inches.
Puddle - Also known as pooling, a build-up of glaze due to its over-application on a ceramic or pottery piece.
Pug Mill - Mixing machine used in pottery to mix and extrude a clay formula from either dry or moist materials.
Pulverizing - Grinding a material to a given screen mesh or fineness. See Grog.
Pumice - A powder that is mixed with water for use in a last abrasive polishing.
Pumicite - A gritty volcanic ash.
Pure Beeswax - Wax extracted from bee hives. It is used to dress wood sculpture, tie dye clothes, and seal wood. Sometimes used as a direct modeling material, but because of its high cost, not often.
Pure Metal - A single non-bonding metal, without alloys.
PVA-Polyvinyl Acetate - Plastic casting resin.
PVA-Polyvinyl Alcohol - Polymerized vinyl compound condensed into a liquid state.
Pyrometer - Device that measures the temperature in a kiln for ceramic and pottery firing.
Quarry - Site where stone is gathered. Stone suitable for carving is found in specific sites in Italy, Western United States, Vermont, etc.
Quench - To cool metal by submersion in oil or water. Term used in the tempering and heat treating process to harden steel tools.
Rack - A drying device or structure for clay pieces not yet fired that allows them to dry with the least amount of distortion.
Raku - Method of firing a special Raku clay body for a desired effect.
Rasp - Hand tool with teeth rather than serrations, used for wood, stone, plaster, or metal. It can be double-ended or single ended with the opposite end attached to a handle. Teeth are hand punched and sharp. Size and coarseness of the teeth vary.
Raw Glaze - Glaze formula component without additives. These are the primary glaze ingredients such as iron oxide, ochre, etc.
Reducing - Taking a large sculpture and making it smaller using a pantograph or reversing the enlarging process.
Reducing Agent - An additive that cuts or thins a base material. For example, shellac is cut by alcohol before applying to a model in mold making.
Reduction Firing - Firing process whereby oxygen is regulated to create a special effect on the fired clay or glaze.
Refractory - Material fired to a high enough level to withstand the high temperatures of firing in a kiln used for shelves and posts.
Regulator - Device that controls the flow of a material into a mold.
Reinforcement - Addition of metal or wood cross sections either on the outside of a mold or in the casting of delicate pieces where extra strength is required.
Relief - Flat one-sided sculpture, also called bas-relief.
Resin - Plastic liquid material designed for casting into specially constructed rubber that can withstand the heat of the curing process.
Respirator - Safety device worn over the nose and mouth to protect the lungs from harmful dust or vapors. Available in a variety of materials and designs.
Retaining Wall - Fence that separates sections of the mold; outside area on a relief mold that restrains mold making material to a given area. Constructed of various materials such as wood, metal, clay, or plastilina.
Rib - Tool used primarily by potters for shaping wet clay that has been thrown on the wheel. Can also be used for leveling or scraping.
Riffler - Small rasp type tool with fine serrated cutting edges used for finishing stone and wood. Also known as a jeweler’s rasp.
Rod - Used to strengthen internal sections of a cast. The rod should be non-corrosive so rust will not bleed through the final casting.
ROMA - Trade name of Sculpture House, Inc. Italian formula plastilina made in the United States using the highest grade materials available. Oil- and wax-base modeling material preferred by professional sculptors.
Roman Joint - Square locking section on a model or mold to keep it from shifting. Used by professional mold makers and casters, it is the most difficult joint to make.
Roman Wax - Hard casting wax used for the investment process in the lost wax casting process. Color may vary from purple to black but its brittleness will remain the same. Usually used for fine detailing before casting rather than for direct modeling.
Roughing Out - Creating the basic geometric form from a large natural piece of wood or stone; also applied to clay and plastilina.
Rondel - Round cape-shaped stone carving tool.
Royal Porcelain - Trade name of Sculpture House, Inc. Porcelain clay formula containing English China clay made exclusively in the United States. Clay is fired at cone 10-12 and produces a translucent effect. It is the most difficult clay material to throw or fire due to its delicate nature.
Running - A build-up of glaze that flows beyond desired boundaries. Also known as pooling.
Running Plaster - Liquid plaster poured before the material sets.
Rust - Reddish coating formed on metal that contains iron, caused by moisture. Rods that are galvanized, when inserted into a cast will sometimes rust through the cast plaster piece.
Rutile - Brown, deep red, or black mineral that gives a brilliant metallic luster to ceramics and pottery when fired in a glaze.
Sager - Box made of fire clay where ceramic pieces are fired. A type of fire clay used in producing high fire pottery.
Salt Bath - A procedure in which steel is heated and treated to harden or temper it.
Salt Firing - Process wherein salt is added when firing pottery to create an unusual effect. The salt is added during the glaze firing.
Salt Glaze - Glaze containing amounts of salt to produce a unique effect when fired.
Sand - Granular material caused by disintegration of rock particles; smaller than gravel but larger than silt. Used in clay bodies for strength and texture.
Sand Bag - Canvas bag filled with sand used to hold stone or wood in place when carving it. Sizes vary with the manufacturer. The bags are secured with Velcro or string. The bags are sold empty.
Sand Blasting - Process to clean stone and bronze using high pressure forced air and fine particles of sand.
Sand Casting - One of the older and more difficult methods of making waxes for bronze casting. Specially designed sand is used to pack the model before the waxes form and the pieces go to the foundry.
Sandstone - Sedimentary rock of quartz sand bound by silica or calcium carbonate. Used for buildings and stone sculpture.
Sapwood - Green wood that still contains its original sap.
Scabbing - Occurs when flakes or small pieces of metal fall from an original cast or metal sculpture.
Scrape - To remove material with a sharp edge, either a wire tool or a rectangular steel scraper.
Scrapers - Heavy duty steel tools used to remove rough resistant material such as plaster when working directly or after casting.
Screen - To sieve or run through a mesh to isolate larger particles or to remove unwanted materials from a formula.
Sculptor - A person who creates sculpture.
Sculptor, Academic - A sculptor who is associated with a school, university or academy, who has knowledge based on formal study.
Sculpture - An object created by a sculptor.
Seam Line - The line where the mold sections join and through which casting material escapes; this line occurs in all types of casting, ceramic, bronze, plaster, etc. and must be removed before firing or finishing.
Sedimentary Rock - A form of organic rock.
Set - The initial hardening of plastilina after mixing and extruding. This hardening must be removed by a second or third mixing prior to packaging.
Setting - The time required for plaster or resin to become solid, but not necessarily cured.
Settling - Occurs when particles added to a liquid drop to the bottom of a container. Plaster sprinkled over water should be left to settle on the bottom of the container to absorb water.
Sgraffito - Design made in ceramic ware or pottery with specialty tools.
Shank Ring - End of a tool used in wood carving or stone carving, where the tang in front of the blade acts as a stopper when attached to the handle.
Shard - Piece or section of broken pottery, term applied especially to fragments found in archeological digs.
Shell - The outer coating of hard set plaster of a mold. In bronze casting, a ceramic shell into which molten bronze can be poured without damage. Also known as the mother mold.
Shellac - Coating material used in mold making and casting when modeling material containing sulfur is used. Also used in mold making as a sealer.
Shelves - Ceramic furniture that holds pottery and ceramics when fired; can withstand the high temperatures of the kiln.
Shim - A separating device to divide sections on a model when the mold is to be made. May be brass, wood, tin, aluminum, clay, or plastilina.
Shivering - An effect of glaze on pottery fired at high temperatures; gives an uneven look.
Shore Hardness - Rigidity, flexibility, or hardness of a rubber used in mold making.
Short - Clay or plastilina that is dry and cracks easily when worked, a condition caused by mixing improper proportions of liquid to dry material in the formula.
Short Bent - Wood carving tool with a curved cutting edge like a “u” in the tip of the tool; creates deep quick cuts in wood.
Shrinkage - The percentage a material contracts at different stages of firing. Ceramic clays may shrink up to 20% from the original to the final fired glaze piece.
Silica - Impure forms of salt that generally occur in crystalline stone. Pulverized, it is a bonding agent in ceramic and pottery clay bodies.
Silicone - Rubber from silicone base material and elastomers used in the production of molds to cast polymers or resins. These molds can withstand the heat of the casting materials when they are mixed and poured creating high temperatures due to their natural reaction .
Single Wire End - A modeling tool with only one cutting end; the opposing end acts as an extension of the fingers in modeling.
Sinter - To cause to fuse together with heat, but without melting.
Size - Glutinous material used to fill pores and as a sealer prior to applying gold leaf.
Sketch - Rough design or model of a sculpture used as a guide to create the final work.
Skew - Diagonally cut carving tool for wood with a 45° angle for cross cutting. Sizes vary from 1/8 to 3 inches.
Skimmer - Professional scoop or spoon used to remove air bubbles from the surface of a mixed solution, such as plaster, before casting.
Skin - Thin covering over latex rubber at the initial setting.
Slag - The refuse of metals or ores.
Slake - To treat with water, as in slaking plaster before casting.
Slip - A liquid clay used in casting ceramic pieces before firing. Usually suspended with a binder to facilitate setting.
Slip Casting - Process in which slip is poured into a mold and left to set to form a layer that can be removed and fired.
Slurry - A liquid composition used in ceramic shell casting. The wax is coated with the material before being burned out so the bronze can be cast.
Smooth-On - Trade name of Smooth-On. A white polyurethane two-part mold rubber chemically activated for use in hollow cavity molds. May be thixotropic.
Soapstone - The softest carving stone, also known as talc block or ore. Available mostly in green and black. Also known as serpentine, Eskimo stone, and steatite.
Soapstone, Black - Extremely hard talc base stone indigenous to Virginia; polishes to a deep black color.
Soda Ash - Sodium carbonate used in ceramic glazes.
Sodium Chloride - Salt.
Solder - A fusing alloy of lead and tin used to join metal.
Soldering - Joining sections together with a soldering gun or by welding with a torch. To attach sections of a sculpture after they have been cast; to rejoin.
Spatula - Flexible oval or round steel tool varying in size, used to smooth models or casts and interior mold wall sections.
Spodumene - Emerald green monoclinic mineral used in ceramic glaze.
Sponge - Natural or synthetic absorbent material used for smoothing and water absorption in pottery and ceramics.
Spraying - Using an air powered tool to coat pottery with glaze or spray rubber in mold making.
Springwood - Soft porous section of wood that develops early in the growing season on the annual ring.
Spur - Hole through which liquid enters the major cavity of a mold when poured into a gate.
Stacking - Process of loading a kiln for firing, placing ceramic ware so it is not inadvertently affected by other pieces.
Stain - Used in ceramics and pottery to give a dull or matte effect in firing. Also used in patination applications as a base coloring.
Steatite - Harder form of soapstone but with the same talc base.
Steel - Iron alloyed with carbon. Creates a hard cutting material with hardness determined by the carbon content; 1095C high carbon steel is used for stone and wood carving tools.
Steel Tools - Sculptors’ tools made of high quality steel shaped and formed for specific uses in working with plaster, wax , and clay.
Steel Wool - Various grades of fine to coarse soft steel shavings used in smoothing and finishing wood, stone, and bronze sculpture.
Stilts - Steel- or ceramic-pronged holding devices used to support glazed pottery when being fired to prevent the glaze from sticking to the shelves.
Stone, Carborundum - A polishing or finishing material made of Carborundum.
Stone Carving - Shaping a stone into a piece of sculpture either by hand or with pneumatic tools.
Stone Carving Stand - Heavy duty wood stand used to support large pieces of stone for carving, usually with a concave resting area on which the stone can be rotated.
Stoneware - Ceramic clay fired to high temperatures and becoming non-porous; a harder material than the earthenware clay bodies due to the fermentation and sedimentation of its base ingredients.
Stop Cut - A cross section cut in wood and stone perpendicular to the grain or a cut that stops the normal progression of removal of wood in a specified area.
Straight Gouge - Wood or stone carving tool with a straight flat edge, stone carving tool most likely beveled.
Stratification - Forming layers in casting, generally caused by pouring non-continuously so the levels cool at different times.
Streaking - Heavy or off-balance coloration in a material, patina, or cast caused when the ingredients have not been properly mixed.
Strike - To hit with a hammer or mallet to remove material from a given area.
Studio - Where amateur or professional sculptors work. Also known as an atelier, from the French.
Stun - Shock treatment, as in dipping hot metal in oil or water in heat treating and tempering.
Styrofoam - Polystyrene plastic of different densities used for casting and direct modeling because of its light weight.
Summerwood - Heavier, less porous part of the annual ring of wood formed during the summer months.
Sweep - The curvature or angle of the cutting edge of a tool.
Symposium, Sculpture - Meeting of sculptors, teachers, and students to discuss and demonstrate sculpture techniques. Johnson Atelier regularly sponsors such events.
Synthetic Beeswax - Artificial wax made with oil, with the characteristics of natural beeswax, and costing far less.
Tacky - Not yet dry or set. A sticky state of rubber before setting or curing.
Talc - Magnesium silicate used in various ceramic and pottery formulas as a binder for plasticity. The base of soapstone ore used in carving. The base ingredient of baby powder.
Tap Drill - Tool used to make an initial hole or indentation; used in mold making or wood sculpture.
Tare Scale - Scale used to determine tare, the weight of a material found by deducting the weight of the container holding the material from the total weight. Used with polyurethane rubber mixes.
Temper - Hardness of steel when the molecular structure has been altered by heat.
Temperature - Degree of heat an object or container can withstand, as the temperature of a kiln for firing pottery or rubber for casting resin.
Tempering - Process in which steel carving tools are hardened. Under heating treatment, the molecules merge to form a hard material.
Template - Device that copies an original, used as a master form.
Tensile Strength - Strength of an object beyond which applied pressure will cause it to break. Hardness of fired clay and cast plaster objects.
Terra Cotta - An orange red color in sculpture; a red clay with grog or a base color for patina.
Texture - Visual or tactile surface of a body or substance; the feel of a certain material. One textures sculpture in a cutting fashion.
Thermal Shock - Stress or reaction caused by heating. May affect clay when firing or steel carving tools when being tempered.
Thermocouple - Used in a kiln to measure the temperature of the interior so one can adjust it as required.
Thinning - Diluting a base component part by mixing with a reducing agent, as shellac mixed with alcohol.
Throwing - Producing pottery on a potter’s wheel (electric or kick wheel) by centering and forcing the clay to take a desired shape as the wheel turns.
Tin - Low melting alloy that is malleable at ordinary temperatures. Used as a component with bronze and lead. Used as a filler and bonding agent.
Tin Oxide - Powder polishing compound that creates a deep luster finish.
Titanium - A strong metallic element used as a binder in refractory materials such as in kiln shelves and posts.
Tongs - Tool used to securely hold a material or ceramic piece while working on it when hand holding it is not feasible.
Tooth - That part of a stone carving tool that cuts a small section; also known as the cutting part on a rack or claw chisel.
Torch - Flame producing device used in wax working and bronze casting; its fuel base is alcohol or propane.
Trailing - Adding a layer or coating of slip or glaze over a ceramic or pottery piece for decorative purposes.
Translucent - Able to transmit light, as in translucent alabaster, a carving stone.
Trimming - Cutting clay away from a piece of pottery or from a footing on a bowl in the leather-hard stage before firing and glazing.
Trimming Tools - Tools designed for trimming pottery.
Triple Beam Balance - Scale used in measuring gram amounts of chemicals and glaze materials for formulas. Most accurate commercial scale used in ceramics.
Tulons - Trade name of Sculpture House, Inc. Wooden tools for burnishing and shaping clay.
Tungsten Carbide - High melting ductile metal used in hardening steel.
Turnette - Small round turntable for working with smaller ceramic objects and sculpture.
Turning - Process by which a piece of wood is shaped on an electric lathe.
Turning Tool - Long-handled high carbon steel wood working tool used to reduce wood forms to the desired effect on a lathe.
Turntable - Platform, generally round, made of wood or metal that turns as one decorates pottery or ceramics. Larger tables on ball bearings are used for large pieces of sculpture.
Umber - Brown earthen mineral used in coloring glaze and clay in ceramics and pottery.
Undercut - An overhang or protrusion of a relatively smooth plane that hinders removal of the mold. Undercuts must be worked around when mold making and casting.
Urethane - Ethyl ester of carbonic acid used as a solvent in an anti-plastic agent. Used in molds and casting material.
“V” Tool - Parting or veining tool used in wood working at 45º and 60º angles for furrowing in wood and stone.
Vacuum - State resulting from the removal of air from rubber or clay before use to avoid air bubbles in the final piece.
Vanadium - Polyvalent metallic used as an alloy as in vanadium steel.
Vapor - Gaseous state as opposed to a solid or liquid state.
Variation - The extent to which items or masses may differ. Raw materials used in formulas, for instance, may vary in quality from year to year depending on the mining level.
Vatican Art Casting Stone - Trade name of Sculpture House, Inc. Artificial casting stone made of gypsum and aggregate to simulate marble. Available in different base colors.
Vent - A channel or opening in a mold through which air and gases may escape thereby preventing damage to the cast or air pockets in the cast.
Vermiculite - A moisture absorbing silicate used as a filler in clay bodies.
Vermont Marble - A hard, white, vein-free marble from Vermont; Barry, Vermont is its center of production.
Vibration - When pouring rubber or plaster, a process of shaking the mold or container to eliminate air bubbles in the rubber or plaster.
Victory Wax - Soft brown wax or Microcrystalline Wax used in bronze casting and direct modeling. Derivative of petroleum.
Viscosity - The rate of flow at which a liquid follows a given path. In sculpture, applied to molten bronze, plaster and other metals able to be cast.
Vise - Gripping device with jaws to secure a piece of sculpture or wood that is being worked.
Vitrification - The process by which a clay body is heated until it becomes non-porous.
Volatilize - To cause to pass off in vapor.
Volcanic Ash - Produced by volcanic eruption, a material used in ceramic glaze formulas.
Volume - Amount of space occupied by a model measured in cubic units.
Warping - Distortion caused by moisture or lack of moisture in wood, and by overfiring in ceramics.
Water Glass - Silicate of sodium and water, used as a protective coating.
Wax - Substance derived from petrolatum refined to be soft, pliable, used for modeling and casting.
Wax, Positive - Wax cast from the mold that will be invested or coated with slurry then melted out. A bronze cast will result when molten bronze is poured into the cavity.
Wax Resist - In pottery and ceramics, the wax coating applied to the interior of kiln walls so glaze will not adhere to the walls in firing.
Wax Tools - Steel tools designed and produced for working with wax. They absorb heat and are especially shaped for their functions.
Weathering - Process of aging outdoors resulting in various colors or patina. Effects will differ depending on geography and climate.
Wedges - Triangular shaped wooden pegs that help secure the tightening of mold straps when casting large pieces.
Wedging - Cutting or rolling a clay body to force out internal air which can cause an explosion or damage when the clay is fired.
Wedging Board - Plaster based slab with a wire cutting device at a 45° angle for cutting pieces of clay to be wedged. May also be made without the cutting wire.
Weld - To bring separate parts together, as in jointing plaster, wax, clay, or bronze sections to form a completed piece.
White Lead - Highly toxic powder or paste with great binding ability. Sometimes used in ceramic glazes and house paint.
White Rubber - A two-part polyurethane rubber with a catalyst setting agent used in making rubber molds.
Whittler - One who works on handheld wood pieces with a small knife.
Winterstone – A Sculpting Medium is an engineered formulation developed by Lorne P. Winters (a civil engineer turned sculptor) for direct modeling and carving of finished, permanent sculptures.
Woodcarver - Person who carves wood in three dimensions with tools and a mallet.
Woodworker - Person who works wood either by handheld or powered tools, as a cabinet maker, wood turner, etc.
Zinc - Metallic element of intermediate hardness that becomes ductile with slight heating.
Zinc Oxide - An infusible white solid used as a pigment in compounding rubber and ceramic glaze.
Zirconium - Metallic element with a high melting point and resistant to corrosion. Used in refractory shelves and posts in the ceramic industry.