Hand Tools
Hand tools
Hand tools
A hand tool is a device for doing a particular job that does not use a motor, but is powered solely by the person using it.
Examples are almost endless, from general tools like the hammer to specific tools like callipers. Some hand tools are mounted to walls, such as pencil sharpeners.
Virtually every type of tool can be a hand tool, although many have also been adopted as power tools, which get their motive power from engines rather than from people. Some hand tools cannot be easily or safely converted to power tools, namely chisels
Examples:
Drill
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A child using an electric drill with a screwdriver bit mounted in the chuck. He is not wearing eye protection, which should always be used when operating power equipment.
A drill is a tool with a rotating drill bit used for drilling holes in various materials. Drills are commonly used in woodworking and metalworking.
The drill bit is gripped by a chuck at one end of the drill, and is pressed against the target material and rotated. The tip of the drill bit does the work of cutting into the target material, slicing off thin shavings (twist drills or auger bits) or grinding off small particles (oil drilling).
Introduction
The earliest drills were probably bow drills. The invention of the electrical drill is credited to Mr. Arthur James Arnot[1], in 1889, at Melbourne, Australia. Wilhelm Fein[2] invented the portable electric drill in 1895, at Stuttgart, Germany. In 1917, Black & Decker patented a trigger-like switch mounted on a pistol-grip handle.[3]
Types
There are many types of drills; some powered manually and others using electricity or compressed air as the motive power. Drills with a percussive action (such as hammer drills, jackhammers or pneumatic drills) are usually used in hard materials such as masonry or rock. As well, drilling rigs are used to bore holes in the earth to obtain water or oil. An oil well, water well, or holes for geothermal heating are created with large drill rigs up to a hundred feet high. Some types of hand-held drills are also used to drive screws.
Fig. Carpenter using a crank-powered brace to drill a hole.
Hand tools
A variety of hand-powered drills have been employed over the centuries. Here are a few, starting with approximately the oldest:
Breast drill, also known as “eggbeater” drill
Push drill, a tool using a spiral ratchet mechanism
Pin chuck, a small hand-held jewellers drill
Hammer Drill
The hammer drill is similar to a standard electric drill, with the exception that it is provided with a hammer action for drilling masonry. The hammer action may be engaged or disengaged as required.
Rotary hammer drill
The rotary hammer drill (also known as roto hammer drill or masonry drill) is an electric drill type dedicated to drilling holes in masonry. The rotary hammer drill is a percussion drill that uses a weight to create the impact force on the masonry bit. Generally, the drill chuck of the rotary hammer drill is designed to hold SDS drill bits. Some styles of this drill are intended for masonry drilling only and the hammer action cannot be disengaged. Other styles allow the drill to be used without the hammer action for normal drilling.
Cordless drills
A cordless drill is a type of electric drill which uses rechargeable batteries. These drills are available with similar features to an AC mains-powered drill. They are available in the hammer drill configuration and most also have a clutch setting which allows them to be used for driving screws.
For continuous use, a worker will have one or more spare battery packs charging while drilling, so that he or she can quickly swap them, instead of having to wait several hours during recharges.
Early cordless drills started with interchangeable 7.2V battery packs, and over the years the battery voltage has been increased to 18V, and higher, allowing these tools to produce as much torque as many mains-powered drills. The drawback of most current models is the use of nickel-cadmium (NiCd) batteries, which develop a “memory effect” or internal short circuits due to dendrite growth, severely limiting their useful life, and posing a hazardous materials disposal problem. Drill manufacturers are now introducing lithium ion batteries, most notably Makita Electric Works and Milwaukee Electric Tool Corporation. The main advantages are lack of memory effect and very short charging time. Instead of charging a tool
for an hour to get 20 minutes of use, 20 minutes of charge can run the tool for an hour. Lithium-ion batteries also have a constant discharge rate. The power output remains constant until the battery is depleted, something that nickel-cadmium batteries also lack, and which makes the tool much more versatile. Lithium-ion batteries also hold a charge for a significantly longer time than nickel-cadmium batteries, about 2 years if not used, vs. around 4 months for a nickel-cadmium battery.
Drill press
Drill press (also known as pedestal drill, pillar drill, or bench drill) is a fixed style of drill that may be mounted on a stand or bolted to the floor or workbench.
Consists of a base, column (or pillar), table, spindle (or quill), and drill head, usually driven by an induction motor. The head has a set of handles (usually 3) radiating from a central hub that, when turned, move the spindle and chuck vertically, parallel to the axis of the column.
The table can be adjusted vertically and is generally moved by a rack and pinion; however, some older models rely on the operator to lift and reclamp the table in position. The table may also be offset from the spindle’s axis and in some cases rotated to a position perpendicular to the column. The size of a drill press is typically measured in terms of swing. Swing is defined as twice the throat distance, which is the distance from the center of the spindle to the closest edge of the pillar. For example, a 16-inch drill press will have an 8-inch throat distance.
A drill press has a number of advantages over a hand-held drill:
less effort is required to apply the drill to the workpiece. The movement of the chuck and spindle is by a lever working on a rack and pinion, which gives the operator considerable mechanical advantage.
the table allows a vise or clamp to position and lock the work in place making the operation secure.
the angle of the spindle is fixed in relation to the table, allowing holes to be drilled accurately and repetitively.
Geared head drill
The geared head drill is identical to the drill press in most respects, however they are generally of sturdier construction and often have power feed installed on the quill mechanism, and safety interlocks to disengage the feed on overtravel. The most important difference is the drive mechanism between motor and quill is through a gear train (there are no vee belts to tension) this makes these drills suitable for the larger sizes of drill bits (16 mm or 5/8ths” upwards) which would normally stall in a drill press.
Radial arm drill
A radial arm drill is a geared head drill that can be moved away from its column along an arm that is radiates from the column. These drills are used for larger work where a geared head drill would be limited by its reach, the arm can swivel around the column so that any point on the surface of the table can be reached without moving the work piece. The size of work that these drills can handle is considerable as the arm can swivel out of the tables area allowing an overhead crane to place the workpiece on the fixed table. Vices may be used with these machines but the work is generally bolted to the table or a fixture
Mill drill
Mill drills are a lighter alternative to a milling machine. They combine a drill press (belt driven) with the X/Y coordinate abilities of the milling machine’s table and a locking collet that ensures that the cutting tool will not fall from the spindle when lateral forces are experienced against the bit. Although they are light in construction, they have the advantages of being space-saving and versatile as well as being suitable for light machining that may otherwise not be affordable.
Chisel
A chisel is a tool with a characteristically shaped cutting edge (such that wood chisels have lent part of their name to a particular grind) of blade on its end, for carving and/or cutting a hard material such as wood, stone, or metal. The handle and blade of some types of chisel are made of metal or wood with a sharp edge in it.
In use, the chisel is forced into the material to cut the material. The driving force may be manually applied or applied using a mallet or hammer. In industrial use, a hydraulic ram or falling weight (‘trip hammer‘) drives the chisel into the material to be cut.
A gouge, one type of chisel, is used, particularly in woodworking, woodturning and sculpture, to carve small pieces from the material. Gouges are most often used in creating concave surfaces. A gouge typically has a ‘U’-shaped cross- section.
Types
Chisels have a wide variety of uses. Many types of chisels have been devised, each specially suited to its intended use. Different types of chisels may be constructed quite differently, in terms of blade width or length, as well as shape and hardness of blade. They may have wooden handles attached or may be made entirely of one piece of metal.
Woodworking chisels
Woodworking chisels range from quite small hand tools for tiny details, to large chisels used to remove big sections of human anatomy, in ‘roughing out’ the shape of a pattern or design. Typically, in woodcarving, one starts with a larger tool, and gradually progresses to smaller tools to finish the detail. One of the largest types of chisel is the slick, used in timber frame construction and wooden shipbuilding. According to their function there are many names given to woodworking chisels, such as:
butt chisel: short chisel with beveled sides and straight edge for creating joints.
carving chisels: used for intricate designs and sculpting; cutting edges are many; such as gouge, skew, parting, straight, paring, and V-groove.
corner chisel: resembles a punch and has an L-shaped cutting edge. Cleans out square holes, mortises and corners with 90 degree angles.
flooring chisel: cuts and lifts flooring materials for removal and repair; ideal for tongue-and-groove flooring.
framing chisel: usually used with mallet; similar to a butt chisel, except it has a longer, slightly flexible blade.
framing slick: a large chisel driven by manual pressure, never struck.
mortise chisel: thick, rigid blade with straight cutting edge and square sides to make mortises and similar joints.
paring chisel: has a long blade which is ideal for cleaning grooves and accessing tight spaces.
skew chisel: has a 60 degree cutting angle and is used for trimming and finishing.
Lathe tools
A lathe tool can be a woodworking chisel designed to cut wood as it is spun on a lathe. These tools have longer handles for more leverage, needed to counteract the tendency of the tool to react to the downward force of the spinning wood being cut or carved. In addition, the angle and method of sharpening is different, a secondary bevel would not be ground on the tool.
Metalworking chisels
Chisels used in metal work can be divided into two main categories, hot chisels, and cold chisels. A hot chisel is used to cut metal that has been heated in a forge to soften the metal.
Cold chisel
A cold chisel is a tool made of tempered steel used for cutting ‘cold’ metals, meaning that they are not used in conjunction with heating torches, forges, etc. 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.
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
Stone chisels are used to carve or cut stone, bricks or concrete slabs. To cut, as opposed to carve, a brick bolster is used; this has a wide, flat blade that is tapped along the cut line to produce a groove, then hit hard in the centre to crack the stone. To increase the force, stone chisels are often hit with club hammers, a heavier type of hammer
A hammer is a tool meant to deliver blows to an object. The most common uses are for driving nails, fitting parts, and breaking up objects. Hammers are often designed for a specific purpose, and vary widely in their shape and structure. Usual features are a handle and a head, with most of the weight in the head. The basic design is hand-operated, but there are also many mechanically operated models for heavier uses.
The hammer is a basic tool of many professions, and can also be used as a weapon. Either way, it is perhaps the oldest human tool, perhaps even older than the earliest Homo species[citation needed].
By analogy, the name hammer has also been used for many mechanical parts and devices that are designed to deliver blows, e.g. in the caplock mechanism of firearms.
Basic design and variations
The essential part of a hammer is the head, a compact solid mass that is able to deliver the blows to the intended target without itself deforming
The opposite side of the head may have a second striking surface; or a claw or wedge to pull nails, or may be shaped like a ball as in the ball-peen hammer and the cow hammer. Some upholstery hammers have a magnetized appendage, to pick up tacks. In the hatchet the hammer head is secondary to the cutting edge of the tool.
Popular hand-powered variations include-
Milkmans hammers – Used for breaking the tops off milk bottles. Extremely popular in the 1970’s
carpenter’s hammers (used for nailing), such as the framing hammer and the claw hammer
construction hammers, including the sledgehammer
HAND TOOLS
