The caliper is simple in design and convenient to use. However, over time, its hinge joint develops play, resulting in free movement. To eliminate the free movement, the hinge pin is slightly compressed or riveted. 

MEASURMENT PROCEDURE:

1.The legs of the caliper are spread apart so that they touch the surface of the object being measured, requiring some effort to move them across it.

2. Dimensions of the object are determined by comparison:

• the distance the legs of the device are spread is compared with a measuring scale
• the distance the legs are spread is measured