Convert blueprints into shop drawings to be followed in the construction or assembly of sheet metal products. Determine project requirements, such as scope, assembly sequences, or required methods or materials, using blueprints, drawings, or written or verbal instructions. Lay out, measure, and mark dimensions and reference lines on material such as roofing panels, using calculators, scribes, dividers, squares, or rulers. Fasten seams or joints together with welds, bolts, cement, rivets, solder, caulks, metal drive clips, or bonds to assemble components into products or to repair sheet metal items. Trim, file, grind, deburr, buff, or smooth surfaces, seams, or joints of assembled parts, using hand tools or portable power tools. Fabricate ducts for high efficiency heating, ventilating, and air conditioning (HVAC) systems to maximize efficiency of systems. Select gauges or types of sheet metal or nonmetallic material, according to product specifications. Finish parts, using hacksaws or hand, rotary, or squaring shears. Shape metal material over anvils, blocks, or other forms, using hand tools. Fabricate or alter parts at construction sites, using shears, hammers, punches, or drills. Transport prefabricated parts to construction sites for assembly and installation. Install assemblies, such as flashing, pipes, tubes, heating and air conditioning ducts, furnace casings, rain gutters, or downspouts in supportive frameworks. Hire, train, or supervise new employees or apprentices. Maintain equipment, making repairs or modifications when necessary.