M3 RENISHAW, Hollow hemisphere styli, ceramic

Hollow hemispherical styli consist of a stylus tip that has been cut off above the equator, in addition, the remaining part of the sphere is partially eroded. The reason for this is a weight reduction, especially for large-diameter spheres, which can save up to 70% of the weight. Hollow hemispheres are produced using a complex manufacturing process in order to achieve maximum weight savings.

Stainless steel shafts are used where special diameter or connections are required. Most of them are used for custom-made devices. They are easy to machine and thus more favorable for special fabrications. Compared to tungsten carbide, however, the bending behavior is considerably worse. Therefore, large diameters are preferred for stainless steel shafts

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