Machinists use their knowledge and a variety of tools to accomplish the task of making a part according to a technical drawing. First of all, a machinist will use measuring tools to determine how much will be cut from a metal piece to make the part. Measuring tools may include calipers, rules or more precise tools such as micrometers. Machinery tools that are used by machinists cut, grind, polish or drill metal or other materials to achieve the final shape of the part. Additionally, machinists use auxiliary tools such as hand tools, tool holders and work holders such as vises or chucks. Machinists must follow proper safety procedures to prevent work accidents due to inattention or haste. They wear safety goggles at all times during operation of machinery equipment.
When a small number of parts is needed, machinists are usually able to make them by manually operating machinery tools to cut, drill or grind metal according to specifications. However, when large-scale production of parts is involved, machinists operate primarily through Computer Numerically Controlled (CNC) machine tools. This is a type of computer guided equipment that cuts and shapes the metal according to precise parameters that are introduced in its settings. It allows the production of a large number of parts, especially in industrial settings, and reduces the probability of human error. Still, this process is feasible and cost-effective only on a large scale, since it requires a lot of work in making the appropriate settings to computer-guided equipment. When unique, custom parts are needed, especially in remote locations such as on a military base, on an island, aboard an aircraft carrier or other naval facilities, machinists will use their skills and experience to produce a part by operating machinery tools by hand.
The work of a machinist may be inspected by an engineer, by a specialist from the quality department, or by a more experienced machinery specialist. Before work on a part is started, the equipment must undergo an adjustment of settings according to specific parameters. This is done by a tool setter or by the machinist, to ensure that production is started with a properly configured piece of equipment to avoid errors and delays.