Make tools, fittings, and small metal pieces used in other products.
Inspects and tests insulated wire and cable for conformance to specifications, using testing instruments, inspection manuals, and blueprints: Measures diameter, wall thickness, concentricity of insulation, and thickness of wire or cable, using microscope, pin gauges, and micrometer. Attaches weights to cable to test adhesion of insulation to cable. Connects sample to electrical outlet and tests effectiveness of insulation under varying voltages, using such instruments as ohmmeter, wheatstone bridge, and galvanometer. Tests wearability of insulation, using twisting device. Tests breaking strength of wire and cable, using tensile testing machine. Examines and feels surface of braided metal shield surrounding insulation to detect imperfections, and cuts off or interlaces protruding metal strands of shield. Cuts insulation with knife and compares composition of insulation with specifications. Stamps mark of approval or rejection on cable tested.