Distance Measurements
Steel or fiberglass tapes are generally used for
making long measurements. Secure the hook end of the
tape. Hold the tape reel in the hand and allow it to
unwind while walking in the direction in which the
measurement is to be taken. Stretch the tape with
sufficient tension to overcome sagging. At the same
time make sure the tape is parallel to an edge or the
surface being measured. Read the graduation on the
tape by noting which line on the tape coincides with the
measurement being taken.
CARE OF RULES AND TAPES
Handle rules and tapes carefully and keep metal
ones lightly oiled to prevent rust. Never allow the edges
of measuring devices to become nicked by striking
them with hard objects. They should preferably be kept
in a wooden box when not in use.
To avoid kinking tapes, pull them straight out from
their casesdo not bend them backward. With the
windup type, always turn the crank clockwiseturning
it backward will kink or break the tape. With the
spring-wind type, guide the tape by hand. If it is
allowed to snap back, it may be kinked, twisted, or
otherwise damaged. Do not use the hook as a stop. Slow
down as you reach the end.
SIMPLE CALIPERS
Simple calipers are used in conjunction with a scale
or rule to determine the thickness or the diameter of a
surface, or the distance between surfaces. The calipers
you will most commonly use are shown in figure 2-9.
2-4
Figure 2-9.Simple calipersnoncalibrated.