MIcrometer Measurements: Notes
Another valuable measuring tool is the micrometer, which can be used for measurements such as bearing journal diameter, cylinder head thickness, valve shim thickness and brake rotor thickness etc. Micrometers also come in configurations for inside measurements as well.
The micrometer scale comes in both fractional and metric varieties. We will cover only the metric micrometer scale in this course.
First you must familiarize yourself with the construction of the micrometer in order to understand how measurements are made.