The direct measuring needle is suitable for detecting simple features that can directly contact the measured surface without obstruction. Tungsten carbide measuring rods have excellent rigidity, especially suitable for measuring needles with smaller ball and rod diameters. Ruby is recognized as the industry standard material for measuring needles and is currently one of the hardest materials available, suitable for most applications. Due to the presence of adhesive wear, it is not recommended to use a ruby probe when scanning aluminum workpieces.
