1. 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 44
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 45 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.
- Always measure stock at right angles.
Using 6-inch rule.
Using rule on surface plate.
2. Short rule and holder. Figure 46 shows how a short steel rule
with holder may be usefully applied to a measurement in a recess inaccessible to
the longer type rule.
3. Narrow rule. The narrow rule is used to advantage in measuring
the depth of a narrow slot (fig 47).
Using small rule and holder.
Using a narrow rule.