Vernier calipers are essential precision measuring instruments widely used in engineering, manufacturing, and scientific applications. They consist of a main scale and a vernier scale that work together to provide highly accurate measurements of both internal and external dimensions.
Vernier calipers consist of several key components. The main scale is fixed and contains the primary measurement markings. The vernier scale slides along the main scale and provides the fine measurement capability. External jaws measure outside dimensions, internal jaws measure inside dimensions, and the depth probe measures depth and height.
To read vernier calipers accurately, follow these steps. First, read the main scale value just before the zero mark of the vernier scale. In this example, it's 2.3 centimeters. Next, find which vernier scale line aligns perfectly with any main scale line. Here, the 7th vernier line aligns, giving 0.07 centimeters. Finally, add both readings: 2.3 plus 0.07 equals 2.37 centimeters.
To measure external dimensions, first open the jaws wider than the object. Place the object between the external jaws, then gently close the jaws until they just touch the object surface. Avoid applying excessive pressure as this can damage both the instrument and the object. Once the jaws are properly positioned, read the measurement from the scales and carefully remove the object.