DIAGONAL PLIERS

Figure 1-53.-Wrench pliers. same as the pliers just described, but the jaw opening adjustment is effected differently. Groove-joint pliers have grooves on one jaw and lands on the other. The adjustment is effected by changing the position of the grooves and lands. The groove-joint pliers are less likely to slip from the adjustment setting when gripping an object. The groove-joint pliers will only be used where it is impossible to use a more adapted wrench or holding device. Many nuts and bolts and surrounding parts have been damaged by improper use of groove-joint pliers. WATER-PUMP PLIERS DIAGONAL PLIERS Water-pump pliers were originally designed for tightening or removing water-pump packing nuts. They were excellent for this job because they have a jaw adjustable to seven different positions. Water-pump pliers (fig. 1-54) are easily identified by their size, jaw teeth, and adjustable slip joint. The inner surface of the jaws consists of a series of coarse teeth formed by deep grooves, a surface adapted to grasping cylindrical objects. GROOVE-JOINT PLIERS Groove-joint pliers (fig. 1-55) are another version of water-pump pliers and are easily identified by the extra-long handles, which make them a very powerful gripping tool. They are shaped approximately the Figure 1-54.-Water-pump pliers. Figure 1-55.-Groove-joint pliers. Diagonal cutting pliers (fig. 1-51) are used for cutting small, light material, such as wire and cotter pins in areas that are inaccessible to the larger cutting tools. Also, since they are designed for cutting only, larger objects can be cut than with the slip-joint pliers. Because the cutting edges are diagonally offset approximately 15 degrees, diagonal pliers are adapted to cutting small objects flush with a surface. The inner jaw surface is a diagonal straight cutting edge. Diagonal pliers should never be used to hold objects, because they exert a greater shearing force than other types of pliers of a similar size. The sizes of the diagonal cutting pliers are designated by the overall length of the pliers. SIDE-CUTTING PLIERS Side-cutting pliers (sidecutters) are principally used for holding, bending, and cutting thin materials or small gauge wire. Sidecutters vary in size and are designated by their overall length. The jaws are hollowed out on one side just forward of the pivot point of the pliers. Opposite the hollowed out portion of the jaws are the cutting edges (fig. 1-51). When holding or bending light metal surfaces, the jaw tips are used to grasp the object. When holding wire, grasp it as near one end as possible because the jaws will mar the wire. To cut small-diameter wire, the side-cutting edge of the jaws near the pivot is used. Never use sidecutters to grasp large objects, tighten nuts, or bend heavy gauge metal, since such operations will spring the jaws. Sidecutters are often called electrician or lineman pliers. They are used extensively for stripping 1-32