Vernier Caliper Functioning and Uses

Vernier Caliper

Introduction To Vernier Caliper

The origin of calipers can be traced back to the 9th A.D. Qin dynasty. The second addition to reducing the margin of error was that of a vernier which was done by a French mathematician Pierre Vernier in 1631.

The main use of Vernier calipers is to measure the internal and external dimensions or distance extremely accurately. Vernier calipers are preferred over other flat devices such as rulers as they have an extremely small reading error that of 0.05mm, which is around 0.0019 inches.

There are mainly two types of vernier calipers, one is manual and has two scales one empirical and one metric, and the other one is the digital vernier caliper which boasts an LCD screen that displays the reading. The manual vernier calipers are still much preferred by the people as they are much cheaper than the digital ones and are not dependent on power.

Preparations For Using Vernier Caliper

  • The different parts: Vernier caliper has two jaws. The small jaw is used to measure the internal diameter of items, and the big jaw is used to measure the external diameter of the items. Some of the Vernier Calipers also have a depth measurement device placed on their other end. The sliding scale or the scale that expands and contracts the jaws is known as the vernier scale, and the main scale is the fixed one.
  • Reading the Vernier caliper’s scales: The measurements are similar to a normal ruler. The caliper section of the device or the main scale has a format of inches and centimetres and may have a smaller divide in between them. The Vernier scale or the sliding scale signifies 1/10th of the smallest division in comparison to the main scale. For a simpler comprehension, the caliper scale is regular sized and the vernier scale in “zoomed in” for more accurate readings.
  • Test the smallest divisions your scale decipher: by counting the number of division in between two numeric’s in your Vernier scale, you will get an idea of what distance every small line signifies.
  • The object should be clean: As the measurements are done with the caliper are at a very minute level even a small amount of dirt or grease can mess up the whole procedure.
  • The locking screw should be loosened: The screw is there to keep the device stable when not in use. As all screws do, turning it clockwise will loosen it and anticlockwise will tighten it.
  • The jaws should be closed: To get the most precise measurement the jaws should be closed, and the reading should be zeroed out. The student if not careful about setting the caliper to zero at the beginning of the experiment will have to correct the data for zero error once the measurements are done.

Using the Vernier Caliper

Vernier Caliper

  • As discussed above the vernier caliper has two jaws. The bigger one tightened around the object whereas, the smaller one is inserted into the opening. The bigger jaws are used to measure the distance between two ends whereas the smaller jaws are used to measure the internal diameter. Both the pair of jaws work by sliding the small scale. The above-mentioned screw can be used to maintain the measurement of the scale.
  • When the sliding scale’s zero matches up with the main scale the student should note down the numeric, it’s on. The scale is read in the same way one would read a ruler and if the result comes out between two values use the lesser one.
  • To read the vernier scale and find out which mark on the scale matches up with its main scale counterpart. The line matching the main scale is not required as we have already taken the reading.
  • The main scale and Vernier scale readings should be added to get the final answer. To get the right answer add the two readings being extremely sure of the units.

Hope this article helps you in understanding how the Vernier Caliper works and how to use the device to its full potential.

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