Vernier caliper masters are used to calibrate and set calipers. The master is superior to gage block calibration because it does not require block stacks, making it much faster to inspect the linear range of the tool. It also indicates wear on the caliper jaws because both the ID and OD jaws are inspected without additional setup.
Calipers, like all precision measuring equipment, require calibration on a regular, established inspection cycle. The vernier caliper master provides multiple checks of the caliper, which is necessary due to the typical rack-and-gear or glass scale design. For both inside and outside jaw measurements, each step is hand lapped on both sides. Steps are in 1/2" increments on English models and 12.70mm increments on Metric models, and the master is black-oxided to prevent rust.
Models
6.00" / 150mm Model — manufactured tolerance ±.0002" or .005mm
12.00" / 300mm Model — manufactured tolerance ±.0005" or .013mm
24.00" / 600mm Model — manufactured tolerance ±.001" or .025mm
A long form certificate and a storage case are available for every model.
