USE/CARE OF HANDTOOLS & MEASURING TOOLS - OD1621 - LESSON 3/TASK 1
It is held against the glass edge when measuring.
This rule is
normally 5 feet long, 5/16 inch thick, and 2 inches wide.
c. Using the Rule.
(1) Select Proper Scale. When using a rule to check a dimension, the
proper graduated scale should be used to control the reading of the
dimension (figure 168, view A, on the following page). If the work being
measured lines up between two graduations on the scale, as shown in views B
and C, in figure 168, and it is not possible to read this dimension to a
1/16 on a 1/16 inch scale, a 1/32 inch scale should be used. If it is still
impossible to read a dimension to a 1/32, a 1/64 inch scale should he used.
(a) Six inch Rule. It is good practice to carefully line up the
end of the rule with the surface from which the measurement is to be taken.
Figure 169 on page 221 shows the mechanic holding the part and the rule
firmly against an angle block. This allows the user to devote his entire
attention to reading the scale correctly.
Figure 170 on page 222
illustrates the use of a rule in checking the location of a gaging surface
from a surface plate.
The surface plate in this case serves as a common
base and locates the rule in relation to the surface on the part measured.