How to Read Measuremements on an Outside Micrometer
- 1). Place the object to be measured in the micrometer and twist the handle until it can be held in place between the spindle and the anvil. The object should be snug but not overtightened.
- 2). Read the linear gauge along the shaft. This will be different depending on the accuracy and units being measured. Usually, this gauge will be abbreviated so that "2" is actually "0.2 inches" for English units and "2.4" would be "0.24 mm" for metric units.
- 3). Read the gauge on the barrel using the axial line on the linear gauge. The markings on the barrel will vary, depending on the accuracy of the linear gauge. A linear gauge that measures quarter-step increments will have a barrel gauge with 25 increments. Half-step linear gauges will have 50 increments on the barrel gauge. A reading of "17" on the barrel gauge would equal "0.017 inches" on an English unit micrometer.
- 4
Micrometer reading 0.276 inches
Combine the two readings. A reading of "2.75" on the on the linear gauge combined with a reading of "1" on the barrel gauge of an English unit outside micrometer would equal "0.276 inches."
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