Figure 3-17. Installing Protractor Head on Rule
Figure 3-18. Loosening Protractor Adjustment
3 Place the rule on the angle being
measured and pivot the protractor head against the
edge. Tighten adjustment screws. See figure 3-19.
4 Read the measured angle on the
(c) Square head. The square head can be
used to determine depth.
1 Slide the square head on the rule.
2 Set the flat surface of the square head
above the edge and adjust the rule until it hits the
bottom, as shown in figure 3-20.
3 Tighten the setscrew.
4 Remove the square and read the
depth indicated on the rule.
Figure 3-19. Checking Angle
Figure 3-20. Determining Depth with the Square