The contact-longline of the probes provides optimal three dimensional centring.The hard ratchet at the scale head creates a vibration that is transmitted to the probe/spindle system. This allows the device to be quickly and correctly centred.Because a constant measuring pressure is developed, the manual „sense“ for measurement is not needed. This provides a repetition accuracy of ± 1µm, regardless of who is measuring. (up to Ø 400)
Although the clutch coupling does permit constant measuring pressure, it does not support centring; it makes tilting in the hole. The scatter is approx. ± 3 – 5 µm. The ratchet permits a better centring, but has certain problems of ist own, since repeated ratcheting causes the cone to penetrate too far into the probe system, thus distorting the results and also causes the scatter.