Fitter (occupation)

A machinist is a person who uses machine tools to make or modify parts, primarily metal parts. This process of machining is accomplished by using machine tools to cut away excess material much as a woodcarver cuts away excess wood to produce his work. In addition to metal, the parts may be made of many other kinds of materials, such as plastic or wood products. The goal of these cutting operations is to produce a part that conforms to a set of specifications, or tolerances, usually in the form of engineering drawings commonly known as blueprints.

Within the title machinist are other specialty titles that refer to specific skills that may be more highly developed to meet the needs of a particular job position. Some examples of these specialty titles are fitter, turning hand, mill hand, and grinder. Also, there are titles that are related but actually are a further development of machinist skills such as tool and die maker, tool maker, trim die maker, die sinker, patternmaker and mold maker. These latter titles are also more commonly found in specialized areas of industry.

A fitter and turner refers to a person who manufactures mechanical parts (turner) and assembles (fitter) those parts together to manufacture a mechanical device.

A machinist is usually called upon when a part needs to be produced from a material by cutting. Such a part may be unique or may be needed in the thousands. This could include a machinery part for a production line or anything that can be made from metal or plastic. Producing a part will often require several steps and more than one machine tool. Each machine tool plays a specific role in cutting away excess material. When large numbers of parts are needed, production planning is required to plan the most logical workflow through a series of machines. Computer numerical controlled (CNC) machines are a special computer-driven tool that can machine a large variety of shapes, and whose use in the workflow depends on the part to be machined.

CNC machines are becoming the standard due to their speed, precision, flexibility, and reduced downtime while changing jobs. Production runs consisting of large numbers of parts are more cost effective (in a local and narrow sense) and commonly referred to as production work in the trade. Conversely, small production runs are sometimes referred to as prototype or jobbing work.

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Wikipedia