by Mike Zecchino, Jeff Dax, and Mark Cobb
Many instruments can be used to measure surface roughness and texture—from handheld gages to ultra-precise interferometers and 3D optical profilers. But not all instruments are intended for all applications: a measurement may produce a number, but whether that number is accurate and valid depends on some basic factors. Knowing the strengths and limitations of your gage(s) can help avoid measurement errors and misinterpretations of process variables that can lead to expensive mistakes on the shop floor.
