Pliers are an instrument that convert a power grip - the curling of the fingers into the palm of the hand - into a precision grip, directing the power of the hand's grip in a precise fashion on to the object(s) to be gripped. The handles are long relative to the shorter nose of the pliers. The two arms thus act as first class levers with a mechanical advantage, increasing the force applied by the hand's grip and concentrating it on the work piece.
The materials used to make pliers consist mainly of steel alloys with additives such as Vanadium and/or Chromium, to improve alloy strength and prevent corrosion. Often pliers have insulated grips to ensure better handling and prevent electrical conductivity
Locking pliers
• Combination pliers or lineman's pliers
• Flat-nose pliers, also known as "duckbill," after their resemblance to a duck's bill. With long, narrow, flat jaws, they are stronger than long-nose (needle-nose) pliers, but less able to reach into really confined spaces
• Round-nose pliers, sometimes called snub-nosed pliers
• Long-nose or needle-nose pliers, which have long, narrow jaws for gripping in confined spaces
• Groove-joint or tongue-and-groove pliers (occasionally called water-pump pliers although technically water-pump pliers are a slip-joint plier in the general configuration of groove-joint pliers; or referred to by the name of a well-known manufacturer, Channellock) - with adjustable jaw sizes, which are designed to grip various sizes of round, hexagon, flat, or similarly shaped objects
• Locking pliers, also called "vice grips" or "mole grips"
• Nail-pulling pliers - an adaptation of the end nipper used for cutting wire; the jaws may be asymmetric, allowing the nail to be pulled out with a rocking motion on the surface in which it is imbedded.
• Glass-breaking / Grozz Pliers (Breaker-grozier pliers).
Cutting pliers (used to sever or pinch off)
• Combination pliers or lineman's pliers
• Diagonal pliers (wire cutters, side-cutting pliers or side cutters) not really pliers as only used for cutting
• Pinching pliers (end-nippers)
• Wire-stripping pliers - cuts and removes insulation on electrical wire while leaving the wire intact
• Needle-nose pliers - designed for gripping, but typically incorporate a cutter for 'one-tool' convenience.
Crimping pliers
• For crimping electrical terminals and connectors (solderless connections)
• For crimping metal rings or tags on livestock
• For crimping metal security seals on cargo carriers
• For crimping an impression on a document - as in a notary's seal
• For crimping laboratory vials
• For crimping bottles with sprayer tops, such as perfume bottles
Rotational pliers
• Developed by NASA engineers to enable an astronaut to turn a nut in zero gravity. The clamping motion of the hand is converted to rotational motion to drive a socket wrench
Screwdriver
A screw has a head with a contour such that an appropriate screwdriver tip can be engaged in it in such a way that the application of sufficient torque to the screwdriver will cause the screw to rotate
Screws
Stanley Yankee No 130A, spiral or ratchet screwdriver
Screwdrivers come in a large variety of sizes to match those of screws, from tiny jeweler's screwdrivers up.
If a screwdriver that is not the right size and type for the screw is used, it is likely that the screw will be damaged in the process of tightening it. This is less important for PoziDriv and SupaDriv, which are designed specifically to be more tolerant of size mismatch. When tightening a screw with force, it is important to press the head hard into the screw, again to avoid damaging the screw.
Screwdriver variations
Jeweler's screwdriver set
Many screwdriver designs have a handle with detachable head (the part of the screwdriver which engages with the screw), called bits as with drill bits, allowing a set of one handle and several heads to be used for a variety of screw sizes and types. This kind of design has allowed the development of electrically powered screwdrivers, which, as the name suggests, use an electric motor to rotate the bit. In such cases the terminology for power drills is used, e.g. "shank" or "collet". Some drills can also be fitted with screwdriver heads.
A number of screwdrivers used to remove faulty electronics from a laptop computer
Many modern electrical appliances, if they use screws at all, use screws with heads of non-standard shape in an attempt to prevent users of the device from easily disassembling them. TORX is one such pattern that has become very widespread, with suitable screwdrivers widely available in electronics stores. Other patterns of security screws are less common, though sets of security heads are, again, readily available.
While screwdrivers are designed for the above functions, they are commonly also used as improvised substitutes for pry bars, levers, and hole punches, as well as other tools.
Files
Swiss Halfround Files
Swiss Threesquare Files
Ball-peen hammer
A 380 mm (15 in) ball-peen hammer.
The original function of the hammer was to "peen" riveted or welded material so that it will exhibit the same elastic behavior as the surrounding material. Specifically, striking the metal imparts a stress at the point of impact which results in strain-hardening of that area. Strain hardening raises the elastic limit of a material into the plastic range without affecting its ultimate strength. A strain-hardened material will not deform under the same low stresses as a non-hardened material. Most metals can be "worked" by such methods until they lose all of their ductile characteristics and become strong but brittle.
The ball-peen hammer is also used to expand and shape the free end of copper roves, light rivets and similar, "setting" the rivet in place to complete the joint. Peening is also the method by which steel drums are formed and tuned.
A ball-peen hammer is also known as an engineer's hammer or a machinist's hammer and may be graded by the weight of the head. It is the mechanic's hammer of choice when making gaskets or driving drift pins.
Hacksaw
Standard hacksaws
A panel hacksaw
Small hand-held hacksaws consist of a metal arch with a handle, that fits around a narrow, rigid blade. The blade has many small saw teeth along one side. The blade can either be attached such that the teeth face away from the handle, resulting in sawing action by pushing, or be attached such that the teeth face toward the handle, resulting in sawing action by pulling. On the push stroke, the arch will bend a little, releasing the tension on the blade. The blade is normally quite brittle, so care needs to be taken to prevent brittle fracture of the blade.
A panel hacksaw eliminates the frame, so that the saw can cut into panels of sheet metal without the length of cut being restricted by the frame. Junior hacksaws are the small variant, while larger mechanical hacksaws are used to cut working pieces from bulk metal.
Large, power hacksaws are sometimes used to replace a band saw in machine shops
Metalworking chisels
Bull Point & Cold Chisel
The name cold chisel comes from its use by blacksmiths to cut metal while it was cold as compared to other tools they used to cut hot metal. This tool is also commonly referred to by the misnomer 'coal chisel'. Because cold chisels are used to form metal, they have a less-acute angle to the sharp portion of the blade than a woodworking chisel. This gives the cutting edge greater strength at the expense of sharpness.
Cold chisels come in a variety of sizes, from fine engraving tools that are tapped with very light hammers, to massive tools that are driven with sledgehammers. Cold chisles are forged to shape and hardened and tempered (to a brown colour) at the cutting edge.
The head of the chisel is chamfered to slow down the formation of the mushroom shape caused by hammering and is left soft to withstand hammer blows.
The are four common types of cold chisel. These are the flat chisel, the most widely known type, which is used to cut bars and rods to reduce surfaces and to cut sheet metal which is too thick or difficult to cut with snips. The cross cut chisel is used for cutting grooves and slots. The blade narrows behind the cutting edge to provide clearance. The round nose chisel is used for cutting semi-circular grooves for oil ways in bearings. The diamond point chisel is used for cleaning out corners or difficult places and pulling over centre punch marks wrongly placed for drilling. Although the vast majority of cold chisels are made of steel, a few are manufactured from beryllium copper, for use in special situations where non-sparking tools are required.
Hardy chisel
A hardy chisel is a type of hot chisel with a square shank, which is held in place with the cutting edge facing upwards by placing it in an anvil's Hardy hole. The hot workpiece cut is then placed over the hardy, and struck with a hammer. The hammer drives the chisel into the hot metal, allowing it to be snapped off with a pair of tongs.
Stone chisels
bolster chisel
