Cyclo instruments offers outside diameter setting masters in the range of 5 mm to 330 mm as per i.S. 4349-1987. These masters are manufactured from alloy steel, these masters are sub zero treated at -80ºc after hardening to arrest dimensional growth in hardened steels. Form variation of the diameter is controlled within it0 grade of tolerance. Ground and lapped masters are having hardness of 60± 2 hrc are calibrated under standards room conditions with reference standards traceable to national standards of length through npl, new delhi. Each master is provided with individual calibration certificate with actual size of the master marked on it by electro etching. These setting masters find their applications in setting the dials of comparators such as comparator stands; dial snaps, air snaps and similar products. There are many advantages, we get by using outside diameter solid one piece masters instead of using slip gauge combinations. It goes away with the use of costly precision slip gauge box; reduces the 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 attachment.
