Lineman's pliers
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Lineman's pliers (US English), also called combination pliers and commonly referred to in the USA as Kleins after a brand name, are a type of pliers used by electricians and other tradesmen for gripping small objects, to cut and bend wire and cable. Lineman's pliers have a gripping joint at their snub nose, and cutting edge in their craw, and insulating handle grips that reduce (but do not eliminate) the risk of electric shock from contact with live wires (versions with properly tested and guaranteed insulation in two colors to make faults visible are also available). Some versions include either an additional gripping or crimping device at the crux of the handle side of the pliers' joint. Lineman's pliers typically are machined from forged steel and the two handles precisely joined with a heavy-duty rivet that maintains the pliers' accuracy even after repeated use under extreme force on heavy-gauge wire.
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[edit] Durability
Lineman's pliers owe their effectiveness to the rigid accuracy of their closing (cutting/gripping) action, and to the durable, forged steel from which they are machined. Although the cutting edge may effectively dull with prolonged use or misuse (for example, cutting large steel screws or wire, cutting live wires that electrically short and melt the tool's cutting edges), this tool is otherwise virtually indestructible because it does not depend on a knife-sharp edge, only a 'breaking' edge.
[edit] Typical uses
[edit] Cutting
Lineman's pliers are an essential item in the electrician's tool complement. They cut, bend, and may be used to strip wire insulation or cable jackets. As with most pliers and scissors or shears, lineman's pliers apply most force closest to the pivot-point of the two handles, so for larger materials, the closer one can get the wire or cable to the joint or 'craw' of the pliers, the easier and cleaner the cut will be.
[edit] Cutting metal-clad (MC) cable
A rotosplit is the ideal tool for this job, but lineman's pliers can be used to first 'crack' the spiral casing of the cable by bending it sharply, partially exposing the insulated wires, inside. This creates a place for the pliers to gain purchase, and, with the application of strong force with two hands, they will cut the cable. To strip the cable, saw through one wrap of the spiral metal casing using a metal-cutting saw blade (for example, on a hack saw or powered reciprocating saw) and then use two pliers to twist the casing sharply and break apart the sections on either side of the saw cut. If no saw or rotosplit is available, it is possible (though laborious) to use lineman's pliers to grasp the end of the cable and unwind 12 inches of stiffly-spiralled aluminum to expose the wire inside.
[edit] Gripping
The most common application of the lineman's pliers in gripping is to twist bare (stripped) wires together, to form a common electrical connection between the wires (wire nuts can be used to enhance this electrical connection and guard against corrosion of the contact-points between wires, as well as to insulate the bared wire ends and provide additional mechanical 'locking' of the junction). The gripping action of lineman's pliers is also used to pull fish-tape ends in a long (high-friction) wire run through conduit, to crimp soft metals, or to pull nails and other fasteners.
[edit] Lineman's pliers substitute for other tools
- Needle-nose pliers: Lineman's pliers are fundamentally the same tool as needle-nose pliers: both tools share a typically solid, machined forged steel construction, durable pivot, gripping nose and cutting craw. The main differences are that the slender nose of the needle-nose pliers enable it to form small diameter bends, and position or support items in awkward places. Needle-nose pliers typically have a lower handle/nose length ratio, reducing the force that can be exerted at the tip. Also, needle-nose pliers tend be available in smaller sizes (for electronics applications, they may be found as small as 1/10 scale of the full-size version).
- Screw-cutter: Lineman's pliers may be used to cut steel screws up to #10, and virtually any dry-wall screw. Although, unlike some multi-purpose wire-stripping pliers, lineman's pliers will not always maintain a clean thread-continuity after the cutting, drywall screws typically will still function in drywall or soft woods such as those used in light-frame construction; driving the screw in reverse with moderate pressure will 'drill' a starter-hole, allowing the remaining threads of a cut screw to engage and draw the screw in normally. A machine screw cut by linemans' pliers may function properly about 75% of the time.
- Crimper: Lineman's pliers sometimes include an integrated crimping device in the craw of the handle side of the pliers' joint. The nose-end grippers of lineman's pliers are designed come about 1/16" short of positive contact, when the pliers are fully closed. The pliers' gripping end may be used to squeeze soft metal flat, and function well as a crimper in some applications.
- Reamer: Lineman's pliers have a tapered nose suitable for reaming the rough edge of a 1" or larger conduit, or cleaning sharp metal from the inside of a standard metal knock-out in an electrical enclosure such as a junction box or breaker panel.
