Glossary
waste mold
This term is used in two contradictory ways. In its most common use: a piece mold made from a model (usually of clay or wax) when the model must be broken apart (wasted) in removing it from the mold. The other use: a mold from which only one cast can be taken, because the mold must be broken apart and discarded in order to release the cast. This is how lost-wax casting is accomplished, for instance. The use of this term is highly problematic then, unless the user immediately explains the meaning intended.
raising
The shaping of a malleable metal such as silver or gold by hammering it around a domed model generally of pitch, to extend it from a sheet to a hollow form.
See Also: boss, emboss, repoussé, sinking, wrought iron
rasp
A course abrasive tool made of metal (usually steel). The abrasive surface has many pointed teeth shaped like tiny pyramids, and typically the surrounding surface is perforated so that dust doesn't clog it. Rasps are used in shaping and smoothing wood, plaster, ivory, stone, etc. Files are generally more finely abrasive than rasps, while rifflers are the most finely abrasive of all rasps.
rebate
In framing, this is the step-shaped cut in the reverse side of the molding which accepts the edge of the canvas, panel, etc.
reduction firing
A method of producing greater depth of color on a clay body by firing ceramics with reduced oxygen in the kiln.
refractory
Resistant to high temperatures. Refractory materials are used for molds in lost wax casting and for kiln furniture on which ceramic ware stands while it is fired.
register
The exact alignment of shapes or edges in various areas of any piece of work. In printmaking, registration is the proper positioning of colors.
reinforced concrete
Concrete with increased tensile strength produced by iron or steel mesh or bars embedded in it. Also called ferroconcrete.
release agent
A substance applied to the inside surfaces and seams of a mold to prevent the casting from adhering to the mold; also variously known as a separator, parting agent, or parting compound. A release agent for casting plaster in a mold may be a thin clay slip, or several applications of a soft liquid soap, petroleum jelly, or thin oil. To permit clay to separate from a mold, apply either powdered chalk or talc as a release agent.
relief
A sculpture that is set on a two-dimensional surface such as clay, stone, or plaster, and which is carved so that there is the illusion of three dimensions.
Example: Donatello's The Resurrection, c. 1460-1466
relief printing
Printing methods in which a block of wood, linoleum or some other material's surface is carved so that an image can be printed from it-- un-carved areas receiving ink which transfers to another surface when the block is pressed against it. Block printing.
remarque
In printmaking, most often in etchings, a sketch originally made by the artist on the margin of his plate to test his tools, often to test the degree of the mordant's biting before immersing the entire plate in the acid bath. Because such remarques were originally intended to be scraped or burnished away before the final edition of the plate is printed, a print with a remarque is often called a remarque proof. In the nineteenth century such remarques came to be so valued that they were often retained as part of the finished print. The subjects of these little drawings typically relate in some way to the larger image. The practice greatly fell out of use in the twentieth century.
See Also: edge
replica
A copy of a painting or sculpture originally done by another artist. Young artists have long been trained by painting replicas of masterpieces.
repoussé
The method of producing metal relief by hammering and/or punching a sheet of metal from the back. The metal is usually hammered into a prepared mold, and then final details are engraved onto the front of the relief. (pr. reh'poo-say")
resin
A natural substance secreted by plants (mostly by trees), which is clear to translucent yellow or brown, such as copal, rosin, and amber, used principally in lacquers, varnishes, inks, adhesives, synthetic plastics, and turpentine. Also, synthetic plastics, including thermoplastic materials such as polyvinyl, polystyrene, and polyethylene and thermosetting materials such as polyesters, epoxies, and silicones that are used with fillers, stabilizers, pigments, and other components to form plastics.
resist
A substance which protects a surface from receiving paints, inks, or dyes. Waxes are commonly used as a resist to the dyes used in batik.
See Also: beeswax, block out, lithography, paraffin (or paraffin wax)
RGB
Red green blue. An additive system for representing the color spectrum using combinations of red, green and blue. Used in video display devices.
riffler
A fine, small, usually double-edged and frequently rounded rasp. The riffler is used in delicate shaping and finishing of a carving. Rifflers are made in different shapes and sizes for work in wood, metal, and stone. Files are generally more finely abrasive than rifflers.
ripsaw
A long-bladed hand-held saw with teeth designed for cutting wood in the same direction as the grain runs.
See Also: circular saw, crosscut saw
risers
In lost wax casting, risers are channels through the mold which allow air to escape as molten metal is poured into the mold. Although such channels are also sprues (or rods), other sprues are runners, through which air and gases can escape.
See Also: rodding
rodding
The process of attaching wax rods to the surface of a wax model in lost wax casting. The rods form the runners and the risers in the mold. In some regions a rod is called a sprue, and rodding is called spruing.
rottenstone
A soft, decomposed limestone. In powder form, rottenstone is used to clean and polish photographs for retouching.
See Also: abrasive
rubbing compound
An abrasive paste used to rub down the surface of a resin sculpture to give it a polished finish.
runner
In lost wax casting, a channel in the mold through which the molten metal flows into the mould from a funnel or runner cup. Channels are made by attaching wax rods to a wax model prior to investment. When the mold is full, the runners fill with metal too. They must then be sawn off and filed. Occasionally they have been incorporated into the design of the final work, and not sawn off. A common example is the tang descending from the base or lowest portion of a sculpture, which is employed to secure the sculpture to its pedestal.
rust
A brown or reddish-brown oxide which forms on iron by corrosion, caused most commonly by exposure to water. A common source of brown pigments.
Download FREE coloring
book pages to color at
home or school.
View Pages »