CARE OF RULES AND TAPES

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 cases—do not bend them backward. With the windup type, always turn the crank clockwise—turning 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 calipers—noncalibrated.