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
