Machinists labor to produce precision parts for a variety of applications. In the production of precision parts, the surface finish of the part plays an integral role in the functionality of the component. Machinists have different tools that they use to determine the surface finish of the parts that they produce.
Electronic gauges are used to measure the actual surface texture of a machined part. Two types of these gauges are used: velocity and displacement. The velocity, also known as an averaging type of gauge, uses a stylus that is drawn across a surface; the vertical moves of the stylus are amplified, recorded and sent to an averaging meter that provides a measurement of the roughness of the surface. Displacement, also known as a profiling type of gauge, is primarily used in laboratories for research and development work. This type of surface measuring tool requires a considerable amount of skill to use the tool and read the data produced.
Interference microscopes use optics to measure a surface finish. An interference microscope allows measurement of the surface without actually touching the surface. These types of surface measuring systems are used in research laboratories, production lines in micro-optics and precision machining industries as well as various other applications.
Comparator gauges allow machinists the ability to measure a surface finish through sight and touch. Comparator gauges come with precision reference specimens for the user to use in comparing surfaces. In checking surface measurements, the specimen is placed next to the work piece and examined visually or by touch as the user runs the tip of his fingernail across the workpiece and specimen. Some of these gauges come with a magnifying tool to help in discerning surface measurements.