The Vernier Caliper

The Caliper. The name itself is generic. But to define it, it is a device used to measure the distance between to symmetrically opposing sides. A caliper can be as simple as a compass with inward or outward-facing points. The tips of the caliper are adjusted to fit across the points to be measured, the caliper is then removed and the distance read by measuring between the tips with a measuring tool, such as a ruler.

They are used in many fields such as metalworking, mechanical engineering, gunsmithing, handloading, woodworking, woodturning and in medicine.

There are many types of Calipers but obviously in relation to this blog, we'll mention a particular type of caliper namely: The Vernier Caliper.

Vernier Calipers are usually found in machine shops or any other area which requires to measure its fabricated dimensions. Without this device, machine shops will be having a hard time for accurate measurement.

Vernier calipers can measure internal dimensions (using the uppermost jaws in the picture at right), external dimensions using the pictured lower jaws, and depending on the manufacturer, depth measurements by the use of a probe that is attached to the movable head and slides along the centre of the body. This probe is slender and can get into deep grooves that may prove difficult for other measuring tools.

The vernier scales may include both metric and inch measurements on the upper and lower part of the scale.

Vernier calipers commonly used in industry provide a precision to a hundredth of a millimetre (10 micrometres), or one thousandth of an inch.

A more precise instrument used for the same purpose is the micrometer.



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