saw

a tool with many cutting points, used for cutting metal, wood, and other materials. The term “saw” is also applied to machine tools and other devices in which a saw is the cutting element. The cutting part of a saw is usually a toothed blade, but there are saws in which the cutter is an abrasive diamond disk or a steel cable; such saws are used to cut materials such as stone and glass.

Saws are distinguished according to their working motion. Thus there are circular saws, which have a rotary motion; jigsaws, whose blades perform a reciprocating motion; and band saws, whose blades are flexible endless belts stretched on two rotating pulleys. Circular-saw blades may be one solid piece of carbon tool steel with teeth cut in, or they may have mounted teeth that are made of high-speed steel or of hard alloy. Jigsaws and band saws usually have teeth that are cut directly into the blade.

Man used small serrated flint tools as early as the Neolithic. Excavations at Troy reveal that saws were used during the Aeneolithic period. The earliest metal saws were made from copper, which was rapidly replaced by bronze. Bronze saws for cutting wood, stone, and bone are common among finds dating from the Bronze Age of various peoples. Steel saws, with edge thicknesses and tooth shapes varying according to intended use, were first used in ancient Rome. Steel saws were widely used in ancient Rus’ in many crafts. Cabinetmakers and wood turners used two kinds of hand saws: jigsaws and bow saws. A jigsaw-type steel saw measuring 39 cm long and having 76 set teeth was found in Novgorod in cultural levels dating from the 11 th century. Old-Russian bone cutters used an assortment of saws.