Machinist - Materials Commonly Encountered By Machinists

Materials Commonly Encountered By Machinists

A machinist is to metal as a woodcarver is to wood. The most common materials that machinists make parts from are steel, aluminum, brass, copper, and various alloys of these materials. Other less common materials such as vanadium, zinc, lead, or manganese are often used as alloying elements for the most common materials. Materials that machinists work with occasionally are plastics, rubber, glass, and wood products. Rarely, machinists also work with exotic and refractory metals. The term exotic metals is a general term describing out of the ordinary, rare or special purpose metals. A synonym might be space-age. A list of exotic metals might include, but is not limited to, titanium, beryllium, vanadium, chromium, molybdenum and tungsten, as well as special high-temperature metal alloys like Inconel or Hastelloy (sometimes called superalloys). Very often the meaning of the term suggests the need for specialized handling and/or tooling to machine them effectively.

While the foregoing were primarily the materials that a machinist would be cutting, the cutters that the machinist uses must be harder and tougher than the materials to be cut. The materials in the cutters a machinist uses are most commonly high speed steel, tungsten carbide, ceramics, Borazon, and diamond.

Machinists usually work to very small tolerances, usually within 0.010" or 0.25 mm (more commonly expressed as ±0.010"(Plus or minus ten-thousands of an inch) or ±0.13 mm), and sometimes at tolerances as low as 0.0001" ((plus or minus one tenth of an thousand of an inch)0.0025 mm) for specialty operations. A machinist deals with all facets of shaping, cutting and some aspects of forming metal, although forming is typically a separate trade. The operations most commonly performed by machinists are milling, drilling, turning, and grinding. There are other more specialized operations that a machinist will less frequently be called upon to perform such as honing, keyseating, lapping, and polishing, to name a few.