Granite surface plates may seem no different than any other working surfaces, but they are actually precision instruments and should be treated accordingly. Despite granite’s toughness and durability, wear spots will form after continual use. These seemingly tiny variations on the surface can cause distortions in measurements and ultimately affect a product’s final quality.
There are two key properties which ensure surface plates provide accurate measurements, repeatability, and flatness. Repeatability represents the ability to reproduce an identical measurement, within an acceptable tolerance, anywhere on the plate. Flatness denotes the difference between the lowest and highest point on the surface plate. Regular surface plate inspections and calibrations are essential to ensure surface plates stay within an acceptable tolerance.