Using the Rule - Continued
Move the steel machinist rule along the stock being measured until the opposite end of the rule is alined
with the mark made in (2) above B (fig. 4-19).
Insure that the edge of the rule is placed against the stock and make another mark, on the stock, at the
6 inch measurement.
Continue to move the steel machinist rule along the stock and mark each 6 inch measurement as
described in steps (3) and (4) above until the entire length of the stock has been measured.
Count the number of marks on the stock and multiply by the length of the rule used to make the
In this example a steel machinist rule is used to measure 18 inches of stock. There are three marks on
3 marks x 6 inches (length of rule) = 18 inches
If the length of the stock to be measured is not an equal multiple of the rule used, make the
measurement as described in steps (1) through (6) above and add to that the length of any remaining
portion of stock that is shorter than the rule.
In this example a 6-inch pocket rule is used to measure 23 inches of stock. There are three marks on
the stock with 5 inches remaining.
3 marks x 6 inches (length of rule) + 5 inches (portion of stock shorter than the rule ) = 23 inches.
Standards of Length.
Two systems, the English and Metric, are commonly used in the design of measuring tools for linear measurements. The
English system uses inches, feet, and yards, while the Metric system uses millimeters, centimeters, and meters. In
relation to each other 1 inch is equivalent to 25.3995 millimeters, or 1 millimeter is equivalent to 0.039370 inch. Refer to
tables 4-2 through 4-7 to facilitate conversion between systems.