Cyclo instruments provides outside diameter setting masters in 5 mm to 330 mm range as per is 43-49-1987 standards for setting the dials of comparators such as comparator stands, dial snaps, air snaps and alike. These masters are made from alloy steel and sub zero treated at 80°c after hardening to arrest dimensional growth in hardened steels. Some of the salient features of this master setting discs/od masters include form variation of diameter controlled within ito tolerance grade; 60 ±2 hrc ground and lapped having hardness; calibrated under standard room conditions with reference standards traceable to national standards of length through npl new delhi; and are supplied with individual calibration certificate for actual size marked by electro etching. The master setting discs/od masters offer advantages like using outside diameter solid one piece masters instead of slip gauge combinations; use of costly precision slip gauge box; reduces incidences of committing errors in building a slip combination leading to heavy losses in the production line; and facilitates the measurement of outside diameters of splined shafts with the help of between centre attachments.
