In comparison measurement, the ruler is the standard that all other comparison measurement tools are gaged by. The measurements that are compared are taken with transfer measuring instruments. A caliper is one kind of transfer measurement tool. Calipers have two legs that make contact with the parts surfaces and they are compared to a ruler to obtain the measurement. Calipers can also be used to scribe radii.
Calipers can measure outside and inside diameters. A slide caliper has a built in ruler that allows measurements to be read directly and not transferred. The most common type of caliper that is used for comparison measurement is the spring type caliper. This type can measure both inside and outside dimensions. The measurement taken has to be compared to a standard such as a ruler. This information provided by: Ladell Humphries, Machine Tool Instructor,humphriesle@cctech.edu.
The caliper is a tool that encompasses various types. In this module, we'll be exploring two specific types; the dial caliper and the vernier caliper. By the end of this unit, you'll be able to identify, read, and calibrate these two types of calipers.