Wind large springs with upward motion of arm. Adjust doors to open or close with the correct amount of effort or make simple adjustments to electric openers. Carry springs to tops of doors, using ladders or scaffolding, and attach springs to tracks to install spring systems. Repair or replace worn or broken door parts, using hand tools. Complete required paperwork, such as work orders, according to services performed or required. Fasten angle iron back-hangers to ceilings and tracks, using fasteners or welding equipment. Collect payment upon job completion. Install door frames, rails, steel rolling curtains, electronic-eye mechanisms, or electric door openers and closers, using power tools, hand tools, and electronic test equipment. Inspect job sites, assessing headroom, side room, or other conditions to determine appropriateness of door for a given location. Assemble and fasten tracks to structures or bucks, using impact wrenches or welding equipment. Set doors into place or stack hardware sections into openings after rail or track installation. Operate lifts, winches, or chain falls to move heavy curtain doors. Remove or disassemble defective automatic mechanical door closers, using hand tools. Fabricate replacements for worn or broken parts, using welders, lathes, drill presses, or shaping or milling machines. Prepare doors for hardware installation, such as drilling holes to install locks. Run low voltage wiring on ceiling surfaces, using insulated staples. Cut door stops or angle irons to fit openings. Study blueprints and schematic diagrams to determine appropriate methods of installing or repairing automated door openers. Install dock seals, bumpers, or shelters.