Make tools, fittings, and small metal pieces used in other products.
Tests fiberglass products, such as bonded cord, insulation mats, roving, and staple lengths to determine if products conform to specifications: Determines breaking strength of bonded cord by mounting sample on arms of testing machine and moving machine controls that apply force necessary to rupture sample. Weighs insulation mat, bonded cord, or roving on balance scales before and after drying and computes percentage of moisture, wax binder, and solids in sample, using slide rule. Observes machines in operation to detect worn equipment, irregular roving packages, or dull cutters. Examines products for defects, such as dirt, frayed ends, clumps in mats, discolorations, and variation in number of ends. Measures staple lengths to verify conformance to standards, using ruler. Tests speed of machine spindles, using tachometer. Records tests results on quality control records and notifies production supervisors, machine repairer, and workers when machine operation, material, or products vary from standards. May perform physical tests to determine yarn porosity, diameter, or denier.