The Vernier Caliper

Reading the caliper and parts of the caliper

Parts of the Caliper

The Vernier Caliper

• The vernier caliper has two main parts which has the scales that the measurements are read from.

• The main beam:this is the non moving part of the unit and contains the main scales, and sub scales • This then is called the main scale, as the main numbers are read here first.

The main scale

• The main scale runs the entire length of the vernier caliper • The scale is similar to the micrometer • There are usually two scales on the main beam. The imperial,and metric scales • The imperial scale runs from 0-6 inches or may be longer the scale is divided into 1 inch segments • The main beam allows for three numbers to be read(1) the whole number full inches( 2) major divisions e.g. 0.400 and ( 3) minor divisions e.g. 0.025 or .050 these are all read on the main beam scale

The main Beam

• The imperial scale has 1 inch divisions which is divided into 1/10 th or 0.100 inches – This scale is also subdivided into four other segments(¼) or 0.025 inches • This main beam scale is then accurate to 0.025 inches.

• On the metric scale the segments are arranged into segments of 1cm or 10 mm

The main beam (metric)

• The main beam segments 1cm is broken down by dividing 1 by 10 =1mm or 0.1 cm • This scale will run up to 150 mm or 15cm or longer • The measurements read here are called the base measurements and is accurate to 1mm, 0.1 cm .They are as follows,1mm or 0.1 cm unlike the imperial scale accuracy is at 1 decimal place.

The vernier Scale

• The vernier scale is the moving scale that slides back and forth along the beam • This moving or sliding scale is a subdivision of the smallest scale on the main beam scale which is either 0.025 inches or 0.1 cm or 1mm.

• This scale contains the focal point (0) which is where the readings are taken from.

• This scale now is broken down into segments by dividing 0.025 inches by 25 • 0.025/25=0.001inches

• The metric scale of 1mm or 0.1cm is broken down by 10 and is usually accurate to 0.02mm or 0.05mm

• 1mm/10=.1mm or 0.01cm

The vernier scale

• This scale on the scale on the metric vernier is accurate to 0.02mm or 0.05 based on the number of segments • The total length of the vernier scale represents 1mm on the on the main beam scale • On the imperial vernier the scale is broken down to read accurate to 0.001 inches and therefore the total length of the vernier represents 1 segment of the main beam scale this may be a 0-25 or 0-50 scale.

Reading the vernier caliper

• The base measurement is read on the main beam left to right of the( 0) on the main beam scale read the main scale.Use the vernier Zero (0) AS THE FOCUS • Look at the graduations on the vernier scale to see which lines up exactly with one on the main scale then read the number on the vernier scale not the main scale • Add these two readings together then check the reading • The total is the measurement of the vernier caliper