How to use and read the dial calipers

How to use the dial calipers?
Step 1
Clean the measuring surfaces of the calipers and the surface of the object to be measured. Both surfaces should be free of obstructive debris to get the most accurate measurement possible.
Step 2
Close the calipers so both measuring jaws are flush together, and make sure the dial reads zero. If the dial does not read zero when the measuring jaws are together, your reading will be inaccurate.
Step 3
Open the jaws of the caliper and place them around the object you wish to measure.
Step 4
Close the jaws around the object, so that each jaw makes a right angle with body of the caliper and there is no space between the jaws and the object.
Step 5
Read the measurement on the ruler scale first. There will be a measurement on the caliper above the object, to the left of the dial that looks like a normal metal ruler.
Step 6
Add the measurement on the ruler scale, to the reading on the dial. The dial measures very small distances that would be more difficult to discern with the naked eye on the ruler scale. The ruler portion measures in larger units such as centimeters and millimeters, while the dial measures in fractions of a millimeter, so adding them up may just be a matter of adding decimal places onto the ruler scale measurement.