M5, Disc styli, ceramic disc, tungsten carbide shaft
Disc styli are used, among other things, to measure rotationally symmetrical workpieces with undercuts or recesses and bores. However, a strong filtering of the surface roughness usually occurs. With the design of the sphercial disk stylus, a higher accuracy is achieved compared to disk styli.
Tungsten carbide is the most common shaft material, it combines a very good stiffness with an acceptable thermal expansion. Only the weight can have a negative effect when using large styli. The straight shaft is the simplest stylus design and the one with the longest usable length. The full shaft length can be used as measuring length. Tungsten carbide shafts represent a good combination in terms of weight, rigidity and thermal expansion.
Ceramic is a very light material and is therefore mainly used for styli spheres with large diameters. Ceramic discs have a very low porosity and a high-precision. They are particularly suitable for scanning rough surfaces such as cast iron