A professional who repairs, services, and installs hydraulic door closers, using machines and handtools. Responsibilities include:

• Disassembles closers, using handtools and vise.
• Immerses parts in solution of caustic soda and water to clean parts.
• Removes encrusted dirt and rust, using electric rotary wire brush and grinding wheel.
• Replaces worn or broken parts.
• Fabricates parts, using lathes, drill presses, shaping and milling machines, and precision measuring instruments, such as micrometers, calipers, and scales.
• Welds cracked closer casings, using acetylene torch.
• Fills oil chamber and packs spindle with leather washers.
• Paints finished door closer.