To measure small objects with an outside micrometer, open the jaws of the tool and slip the object between the spindle and the anvil. While holding the object against the anvil turn the thimble using your thumb and forefinger until the spindle contacts the object. Use only while continuing to slip the micrometer over the object until you feel a very slight resistance. Rock the micrometer from side to side while doing this to make sure the spindle can’t be closed any further. Lock the micrometer and take a measurement reading.
Some technicians use a digital micrometer, which is easier to read. These tools do not have the various scales; the measurement is displayed and read directly off the micrometer.