1.
Straight edge
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Straight edge is a subculture of hardcore punk whose adherents refrain from using alcohol, tobacco and other recreational drugs, in reaction to the excesses of punk subculture. For some, this extends to refraining from engaging in sex, following a vegetarian or vegan diet. The term straight edge was adopted from the 1981 song Straight Edge by the punk band Minor Threat. Straight edge emerged amid the early-1980s hardcore punk scene, since then, a wide variety of beliefs and ideas have been associated with some members of the movement, including vegetarianism and animal rights. Ross Haenfler writes that as of the late 1990s, approximately three out of four straight edge participants were vegetarian or vegan, disagreements often arise as to the primary reasons for living straight edge. Straight edge politics are primarily left-wing and revolutionary but there have been conservative offshoots, in 1999, William Tsitsos wrote that straight edge had gone through three eras since its founding in the early 1980s. Bent edge began as a counter-movement to straight edge by members of the Washington, D. C. hardcore scene who were frustrated by the rigidity and intolerance in the scene. During the youth crew era, which started in the mid-1980s, by the early 1990s, militant straight edge was a well-known part of the wider punk scene. In the early to mid-1990s, straight edge spread from the United States to Northern Europe, Eastern Europe, the Middle East, by the beginning of the 2000s, militant straight edge punks had largely left the broader straight edge culture and movement. While some straight edge groups are treated as a gang by law enforcement officials, Straight edge has often been approached with skepticism and hostility, despite the ideologically less dogmatic and more multifaceted character of contemporary straight edge. In the 1970s, the subculture was associated with the use of intoxicative inhalants. In 1999, William Tsitsos wrote that straight edge had gone through three eras since its founding in the early 1980s, later analysts have identified another era that has taken place since Tsitsoss writing. Straight edge grew out of punk in the late 1970s and early 1980s. Straight edge individuals of this era often associated with the original punk ideals such as individualism, disdain for work and school. Straight edge sentiments can be found in songs by the early 1980s band Minor Threat and this anti-inebriation movement had been developing in punk prior to Minor Threat, but their song Straight Edge was influential in giving the scene a name, and something of a figurehead. Minor Threat frontman Ian MacKaye is often credited with birthing the Straight edge name and movement, Straight edge sentiments can also be found in the song Keep it Clean by English punk band The Vibrators, and the 1970s Modern Lovers song Im Straight. As one of the few prominent 1970s hard rock icons to explicitly eschew alcohol and drug use, Straight edge started on the East Coast of the United States in Washington D. C. and quickly spread throughout the United States and Canada. By the 1980s, bands on the West Coast, such as Americas Hardcore, Stalag 13, Justice League, in the early stages of this subcultures history, concerts often consisted of both punk bands and straight edge bands
2.
Scale ruler
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An architects scale is a specialized ruler designed to facilitate the drafting and measuring of architectural drawings, such as floor plans and orthographic projections. Because the scale of such drawings are often smaller than life-size, for accuracy and longevity, the material used should be dimensionally stable and durable. Scales were traditionally made of wood, but today they are made of rigid plastic or aluminium. Architects scales may be flat, with 4 scales, or have a symmetric 3-lobed cross-section, in the United States, and prior to metrification in Britain, Canada and Australia, architects scales are/were marked as a ratio of x inches-to-the-foot. It is not to be confused with a true unitless ratio -- a 1,5 architectural scale would be a 1,60 unitless scale, therefore, a drawing will indicate both its scale and the unit of measurement being used. In Britain, and elsewhere, the units used on architectural drawings are the units millimetres and metres. In Britain, for rulers, the paired scales often found on architects scales are, For triangular rulers
3.
Ruler
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A ruler, sometimes called a rule or line gauge, is an instrument used in geometry, technical drawing, printing, engineering and building to measure distances or to rule straight lines. The ruler is a straightedge which may also contain calibrated lines to measure distances, rulers have long been made from different materials and in a wide range of sizes. Plastics have also used since they were invented, they can be molded with length markings instead of being scribed. Metal is used for more durable rulers for use in the workshop,12 inches or 30 cm in length is useful for a ruler to be kept on a desk to help in drawing. Shorter rulers are convenient for keeping in a pocket, longer rulers, e. g.18 inches are necessary in some cases. Rigid wooden or plastic yardsticks,1 yard long, and meter sticks,1 meter long, are also used, classically, long measuring rods were used for larger projects, now superseded by tape measure or laser rangefinders. Desk rulers are used for three purposes, to measure, to aid in drawing straight lines and as a straight guide for cutting and scoring with a blade. Practical rulers have distance markings along their edges, a line gauge is a type of ruler used in the printing industry. These may be made from a variety of materials, typically metal or clear plastic, units of measurement on a basic line gauge usually include inches, agate, picas, and points. More detailed line gauges may contain sample widths of lines, samples of common type in several point sizes, measuring instruments similar in function to rulers are made portable by folding or retracting into a coil when not in use. When extended for use, they are straight, like a ruler, the illustrations on this page show a 2-meter carpenters rule, which folds down to a length of 24 cm to easily fit in a pocket, and a 5-meter-long tape, which retracts into a small housing. A flexible length measuring instrument which is not necessarily straight in use is the tailors fabric tape measure and it is used to measure around a solid body, e. g. a persons waist measurement, as well as linear measurement, e. g. inside leg. It is rolled up when not in use, taking up little space, a contraction rule is made having larger divisions than standard measures to allow for shrinkage of a metal casting. They may also be known as a shrinkage or shrink rule, a ruler software program can be used to measure pixels on a computer screen or mobile phone. These programs are known as screen rulers. In geometry, a ruler without any marks on it may be used only for drawing lines between points. A straightedge is used to help draw accurate graphs and tables. A ruler and compass construction refers to using an unmarked ruler
4.
Laser line level
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A laser line level is a tool combining a spirit level and/or plumb bob with a laser to display an accurately horizontal or vertical illuminated line on a surface the laser line level is laid against. Laser line levels are used wherever accurate verticals and horizontals are required, typically in the construction, some models are inexpensive enough for do-it-yourself applications. The laser beam is fanned to produce a thin plane beam accurately horizontal or vertical, a more advanced device may be accurate to within 0.3 mm/m, while lower-end models may be closer to 1.5 mm/m. The illuminated line is necessarily absolutely straight, so that the level can be used as a straightedge, for example, to see if a shelf is warped. Dumpy level Theodolite List of laser articles Laser Machine Control Checking a level for accuracy
5.
Winding stick
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In woodworking and carpentry, a pair of winding sticks is a tool that aids in viewing twist or wind in pieces of lumber by amplifying the defect. Winding sticks can be as simple as any two straight sticks or they can be elegant, decorated, dimensionally stable wood like mahogany, a pair of framing squares may also be suitable. Traditionally they are 16 inches to 30 inches long 1.75 inches tall, the longer the winding sticks, the more they will amplify the wind. One winding stick is placed on one end of the piece and the second winding stick is placed on the other end, the woodworker then stands back a short distance and sights across the top of the two sticks. If the surface on which the sticks are sitting is flat, adjustments to the surface of the board are then made. This process is repeated all across the piece until the piece is satisfactorily true, longitudinally the piece is checked with a straightedge
6.
Compass-and-straightedge construction
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The idealized ruler, known as a straightedge, is assumed to be infinite in length, and has no markings on it and only one edge. The compass is assumed to collapse when lifted from the page, more formally, the only permissible constructions are those granted by Euclids first three postulates. It turns out to be the case that every point constructible using straightedge, the ancient Greek mathematicians first conceived compass-and-straightedge constructions, and a number of ancient problems in plane geometry impose this restriction. The ancient Greeks developed many constructions, but in cases were unable to do so. Gauss showed that some polygons are constructible but that most are not, some of the most famous straightedge-and-compass problems were proven impossible by Pierre Wantzel in 1837, using the mathematical theory of fields. In spite of existing proofs of impossibility, some persist in trying to solve these problems, in terms of algebra, a length is constructible if and only if it represents a constructible number, and an angle is constructible if and only if its cosine is a constructible number. A number is constructible if and only if it can be using the four basic arithmetic operations. Circles can only be starting from two given points, the centre and a point on the circle. The compass may or may not collapse when its not drawing a circle, the straightedge is infinitely long, but it has no markings on it and has only one straight edge, unlike ordinary rulers. It can only be used to draw a segment between two points or to extend an existing segment. The modern compass generally does not collapse and several modern constructions use this feature and it would appear that the modern compass is a more powerful instrument than the ancient collapsing compass. However, by Proposition 2 of Book 1 of Euclids Elements, although the proposition is correct, its proofs have a long and checkered history. Eyeballing it and getting close does not count as a solution and that is, it must have a finite number of steps, and not be the limit of ever closer approximations. One of the purposes of Greek mathematics was to find exact constructions for various lengths, for example. The Greeks could not find constructions for these three problems, among others, Squaring the circle, Drawing a square the same area as a given circle, doubling the cube, Drawing a cube with twice the volume of a given cube. Trisecting the angle, Dividing a given angle into three smaller angles all of the same size, for 2000 years people tried to find constructions within the limits set above, and failed. All three have now been proven under mathematical rules to be generally impossible, the ancient Greek mathematicians first attempted compass-and-straightedge constructions, and they discovered how to construct sums, differences, products, ratios, and square roots of given lengths. They could also construct half of an angle, a square whose area is twice that of another square, a square having the same area as a given polygon
7.
Euclidean geometry
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Euclidean geometry is a mathematical system attributed to the Alexandrian Greek mathematician Euclid, which he described in his textbook on geometry, the Elements. Euclids method consists in assuming a set of intuitively appealing axioms. Although many of Euclids results had been stated by earlier mathematicians, Euclid was the first to show how these propositions could fit into a comprehensive deductive and logical system. The Elements begins with plane geometry, still taught in school as the first axiomatic system. It goes on to the geometry of three dimensions. Much of the Elements states results of what are now called algebra and number theory, for more than two thousand years, the adjective Euclidean was unnecessary because no other sort of geometry had been conceived. Euclids axioms seemed so obvious that any theorem proved from them was deemed true in an absolute, often metaphysical. Today, however, many other self-consistent non-Euclidean geometries are known, Euclidean geometry is an example of synthetic geometry, in that it proceeds logically from axioms to propositions without the use of coordinates. This is in contrast to analytic geometry, which uses coordinates, the Elements is mainly a systematization of earlier knowledge of geometry. Its improvement over earlier treatments was recognized, with the result that there was little interest in preserving the earlier ones. There are 13 total books in the Elements, Books I–IV, Books V and VII–X deal with number theory, with numbers treated geometrically via their representation as line segments with various lengths. Notions such as numbers and rational and irrational numbers are introduced. The infinitude of prime numbers is proved, a typical result is the 1,3 ratio between the volume of a cone and a cylinder with the same height and base. Euclidean geometry is a system, in which all theorems are derived from a small number of axioms. To produce a straight line continuously in a straight line. To describe a circle with any centre and distance and that all right angles are equal to one another. Although Euclids statement of the only explicitly asserts the existence of the constructions. The Elements also include the five common notions, Things that are equal to the same thing are also equal to one another
8.
Compass (drawing tool)
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A pair of compasses, also known simply as a compass, is a technical drawing instrument that can be used for inscribing circles or arcs. As dividers, they can also be used as tools to measure distances, Compasses can be used for mathematics, drafting, navigation and other purposes. Compasses are usually made of metal or plastic, and consist of two connected by a hinge which can be adjusted to allow the changing of the radius of the circle drawn. Typically one part has a spike at its end, and the part a pencil. Prior to computerization, compasses and other tools for manual drafting were often packaged as a bow set with interchangeable parts, today these facilities are more often provided by computer-aided design programs, so the physical tools serve mainly a didactic purpose in teaching geometry, technical drawing, etc. Compasses are usually made of metal or plastic, and consist of two connected by a hinge which can be adjusted to allow the changing of the radius of the circle drawn. Typically one part has a spike at its end, and the part a pencil. The handle is usually half a inch long. Users can grip it between their pointer finger and thumb, there are two types of legs in a pair of compasses, the straight or the steady leg and the adjustable one. Each has a purpose, the steady leg serves as the basis or support for the needle point. The screw on your hinge holds the two legs in its position, the hinge can be adjusted depending on desired stiffness, the tighter the screw the better the compass’ performance. The needle point is located on the leg, and serves as the center point of circles that are drawn. The pencil lead draws the circle on a paper or material. This holds the lead or pen in place. Circles can be made by fastening one leg of the compasses into the paper with the spike, putting the pencil on the paper, the radius of the circle can be adjusted by changing the angle of the hinge. Distances can be measured on a map using compasses with two spikes, also called a dividing compass, to use a pair of compasses, place the points on a ruler and open it to the measurement of ½ of the measurement of the circle that is desired. For instance, if one desires to draw a 3 inch circle, next, place the point on the spot that you wish the center of your circle to be, and then rotate the section that has the pencil lead around the point, using the handle. Compasses-and-straightedge constructions are used to illustrate principles of plane geometry, although a real pair of compasses is used to draft visible illustrations, the ideal compass used in proofs is an abstract creator of perfect circles
9.
Chalk line
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A chalk line or chalk box is a tool for marking long, straight lines on relatively flat surfaces, much farther than is practical by hand or with a straightedge. A chalk line draws straight lines by the action of a nylon or similar string that has been previously coated with a loose dye. The string is then laid across the surface to be marked and pulled tight, next, the string is then plucked or snapped sharply, causing the string to strike the surface, which then transfers its chalk to the surface along that straight line where it struck. Chalk lines are used to mark relatively flat surfaces. However, as long as the line is taut and the two ends of the line are in nearly the same plane, the chalk line will mark all points that the string touches on or near that plane once snapped. The objects to be marked do not need to be continuous along the line, Chalk lines can also be used across irregular surfaces and surfaces with holes in them, for example on an unfinished stud wall. The primary problems associated with maintenance of a chalk line are string breakage due to excessive tension on the line. Chalk lines and plumb-bobs are often sold as a single tool, Chalk lines have been in use since ancient Egypt, and used continuously by builders in various cultures since. Continuing development of simple but effective tool focuses on the coloration for the chalk or marking compound, as well as the outer case. In East Asia, an ink line is used in preference to a chalk line and this is a silken cord, stored on a combined reel and inkpot called a sumitsubo in Japanese. Alongside the line reel is a cavity filled with ink-soaked cotton fibres and these sumitsubo are highly decorated and much-prized by their owners. As with many tools, theyre often made by their users while apprentices. On the completion of a building, such as a temple. As part of event, a set of symbolic carpenters tools are freshly made. A sumitsubo is a tool included with them. Measuring tape Chalk line – One person operation Chalk line – Two-person operation Hand-made chalk-line
10.
Metalworking
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Metalworking is the process of working with metals to create individual parts, assemblies, or large-scale structures. The term covers a range of work from large ships and bridges to precise engine parts. It therefore includes a wide range of skills, processes. Metalworking is a science, art, hobby, industry and trade and its historical roots span cultures, civilizations, and millennia. Metalworking has evolved from the discovery of smelting various ores, producing malleable and ductile metal useful for tools, modern metalworking processes, though diverse and specialized, can be categorized as forming, cutting, or joining processes. Todays machine shop includes a number of machine tools capable of creating a precise, the oldest archaeological evidence of copper mining and working was the discovery of a copper pendant in northern Iraq from 8,700 BCE. The earliest substantiated and dated evidence of metalworking in the Americas was the processing of copper in Wisconsin, Copper was hammered until brittle then heated so it could be worked some more. This technology is dated to about 4000-5000 BCE, the oldest gold artifacts in the world come from the Bulgarian Varna Necropolis and date from 4450 BCE. Not all metal required fire to obtain it or work it, isaac Asimov speculated that gold was the first metal. His reasoning is that by its chemistry it is found in nature as nuggets of pure gold, in other words, gold, as rare as it is, is sometimes found in nature as the metal that it is. There are a few metals that sometimes occur natively. Almost all other metals are found in ores, a mineral-bearing rock, another feature of gold is that it is workable as it is found, meaning that no technology beyond a stone hammer and anvil to work the metal is needed. This is a result of properties of malleability and ductility. The earliest tools were stone, bone, wood, and sinew, at some unknown point the connection between heat and the liberation of metals from rock became clear, rocks rich in copper, tin, and lead came into demand. These ores were mined wherever they were recognized, remnants of such ancient mines have been found all over Southwestern Asia. Metalworking was being carried out by the South Asian inhabitants of Mehrgarh between 7000–3300 BCE, the end of the beginning of metalworking occurs sometime around 6000 BCE when copper smelting became common in Southwestern Asia. Ancient civilisations knew of seven metals. Here they are arranged in order of their potential, Iron +0.44 V
11.
Bandsaw
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A bandsaw is a saw with a long sharp blade consisting of a continuous band of toothed metal stretched between two or more wheels to cut material. They are used principally in woodworking, metalworking, and lumbering, advantages include uniform cutting action as a result of an evenly distributed tooth load, and the ability to cut irregular or curved shapes like a jigsaw. The minimum radius of a curve is determined by the width of the band, most bandsaws have two wheels rotating in the same plane, one of which is powered, although some may have three or four to distribute the load. The blade itself can come in a variety of size and tooth pitch which enables the machine to be versatile and able to cut a wide variety of materials including wood, metal. Almost all bandsaws today are powered by an electric motor, line shaft versions were once common but are now antiques. Constant flexing of the blade over the wheels caused either the material or the joint welding it into a loop to fail, nearly 40 years passed before Frenchwoman Anne Paulin Crepin devised a welding technique overcoming this hurdle. She applied for a patent in 1846, and soon sold the right to employ it to manufacturer A. Perin & Company of Paris. Combining this method with new alloys and advanced tempering techniques allowed Perin to create the first modern band saw blade. The first American band saw patent was granted to Benjamin Barker of Ellsworth, Maine, the first factory produced and commercially available band saw in the U. S. was by a design of Paul Prybil. Power hacksaws were once common in the industries, but bandsaws. Many workshops in residential garages or basements and in light industry contain small or medium-sized bandsaws that can cut wood, metal, often a general-purpose blade is left in place, although blades optimized for wood or metal can be switched out when volume of use warrants. Most residential and commercial bandsaws are of the vertical type mounted on a bench or a cabinet stand, Portable power tool versions, including cordless models, are also common in recent decades, allowing building contractors to bring them along on the truck to the jobsite. Saws for cutting meat are typically of all steel construction with easy to clean features. The blades either have fine teeth with heat treated tips, or have plain or scalloped knife edges, bandsaws dedicated to industrial metal-cutting use, such as for structural steel in fabrication shops and for bar stock in machine shops, are available in vertical and horizontal designs. Typical band speeds range from 40 feet per minute to 5,000 feet per minute, although specialized bandsaws are built for friction cutting of hard metals, metal-cutting bandsaws are usually equipped with brushes or brushwheels to prevent chips from becoming stuck in between the blades teeth. Systems which cool the blade with cutting fluid are also common equipment on metal-cutting bandsaws, the coolant washes away swarf and keeps the blade cool and lubricated. Horizontal bandsaws hold the workpiece stationary while the blade swings down through the cut and this configuration is used to cut long materials such as pipe or bar stock to length. Thus it is an important part of the facilities in most machine shops, the horizontal design is not useful for cutting curves or complicated shapes
12.
Cold saw
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This is contrast to an abrasive saw, which abrades the metal and generates a great deal of heat absorbed by the material being cut and saw blade. As metals expand when heated, abrasive cutting causes both the material being cut and blade to expand, resulting in increased effort to produce a cut and this produces more heat through friction, resulting in increased blade wear and greater energy consumption. Cold saws use either a high speed steel or tungsten carbide-tipped. They are equipped with a motor and a gear reduction unit to reduce the saw blades rotational speed while maintaining constant torque. This allows the HSS saw blade to feed at a constant rate with a high chip load per tooth. Cold saws are capable of machining most ferrous and non-ferrous alloys, additional advantages include minimal burr production, fewer sparks, less discoloration and no dust. Saws designed to employ a flood coolant system to keep saw blade teeth cooled and lubricated may reduce sparks, cold saw blades are circular metal cutting saw blades categorized into two types, solid HSS or tungsten carbide-tipped. Both types of blades are resharpenable and may be used many times before being discarded. Cold saw blades are used to cut metal using a relatively slow speed, usually less than 5000 surface feet per minute. These blades are driven by a high motor and high-torque gear reduction unit or an AC vector drive. During the cutting process, the metal is released in an action by the teeth as the blade turns. They are called cold saw blades because they transfer all the energy and this enables the blade and the work material to remain cold. The first type of cold saw blade, solid HSS, may be made from either M2 tool steel or M35 tool steel, solid HSS saw blades are heat treated and hardened to 64/65 HRC for ferrous cutting applications and 58/60 HRC for non-ferrous cutting applications. This high hardness gives the cutting edges of the teeth a high resistance to heat, however, this increased hardness also makes the blades brittle and not very resistant to shock. In order to produce a high quality HSS cold saw blade, you must start with very flat, the blades must be press quenched after hardening to prevent them from being warped. HSS saw blades are typically hollow ground for clearance during the cutting process, the term HSS doesnt necessarily mean what it implies. These blades are usually never run at speeds higher than 350 SFM. Solid HSS cold saw blades may be used for cutting many different shapes and types of metal including, tubes, extrusions, structural sections, billets, bars, ingots, castings, forgings etc
13.
Laser cutting
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Laser cutting works by directing the output of a high-power laser most commonly through optics. The laser optics and CNC are used to direct the material or the laser beam generated, a typical commercial laser for cutting materials would involve a motion control system to follow a CNC or G-code of the pattern to be cut onto the material. The focused laser beam is directed at the material, which then melts, burns, vaporizes away, or is blown away by a jet of gas. Industrial laser cutters are used to cut flat-sheet material as well as structural, in 1965, the first production laser cutting machine was used to drill holes in diamond dies. This machine was made by the Western Electric Engineering Research Center, in 1967, the British pioneered laser-assisted oxygen jet cutting for metals. In the early 1970s, this technology was put into production to cut titanium for aerospace applications. At the same time CO2 lasers were adapted to cut non-metals, such as textiles, because, at the time, generation of the laser beam involves stimulating a lasing material by electrical discharges or lamps within a closed container. As the lasing material is stimulated, the beam is reflected internally by means of a partial mirror, mirrors or fiber optics are typically used to direct the coherent light to a lens, which focuses the light at the work zone. The narrowest part of the beam is generally less than 0.0125 inches. Depending upon material thickness, kerf widths as small as 0.004 inches are possible, in order to be able to start cutting from somewhere other than the edge, a pierce is done before every cut. Piercing usually involves a high-power pulsed laser beam which slowly makes a hole in the material, taking around 5–15 seconds for 0. 5-inch-thick stainless steel, for example. The parallel rays of coherent light from the laser source often fall in the range between 0. 06–0.08 inches in diameter. This beam is focused and intensified by a lens or a mirror to a very small spot of about 0.001 inches to create a very intense laser beam. In order to achieve the smoothest possible finish during contour cutting, for sheet metal cutting, the focal length is usually 1. 5–3 inches. Advantages of laser cutting over mechanical cutting include easier workholding and reduced contamination of workpiece, precision may be better, since the laser beam does not wear during the process. There is also a chance of warping the material that is being cut. Some materials are very difficult or impossible to cut by more traditional means. There are three types of lasers used in laser cutting
14.
Miter saw
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A miter saw is a saw used to make accurate crosscuts and miters in a workpiece. A power miter saw, also known as a saw, is a power tool used to make a quick. Common uses include framing operations and the cutting of molding and trim, most miter saws are relatively small and portable, with common blade sizes ranging from eight to twelve inches. The miter saw makes cuts by pulling a spinning saw blade down onto a workpiece in a short. The workpiece is held against a fence, which provides a precise cutting angle between the plane of the blade and the plane of the longest workpiece edge. In standard position, this angle is fixed at 90°, a primary distinguishing feature of the miter saw is the miter index that allows the angle of the blade to be changed relative to the fence. While most miter saws enable precise one-degree incremental changes to the miter index, there are several types of power miter saws, Miter saws are dedicated cross cut saws, long rip cuts are not possible. A laser guide provides a visual indication of where the cut will be positioned on the workpiece in the current configuration. Some models provide a reference line for one side of the kerf. A blade guard is a cover for the teeth of the cutting blade, most modern miter saws have self-retracting blade guards, which automatically retract when the saw is lowered onto a workpiece and re-cover the blade when the saw is raised. It is very dangerous to use the saw if these guards are removed or damaged, a dust bag connects directly to the saw, and helps to collect sawdust away from the workpiece during cutting. Optionally, many manufacturers sell adapters to connect an industrial vacuum cleaner in lieu of a bag to capture more of the dust, dust removal with these saws is notoriously poor. A safety clamp helps to lock a workpiece into position prior to making a cut and this is an especially important feature when cutting smaller workpieces. The miter table is typically less than 24 in diameter, typically, the work will need to be supported on the far end to stabilize the piece while cutting. Miter saws are inherently low hazard as the workpiece is held stationary against a fence while the saw head moves, making kick back almost impossible, also the saw head is usually drawn back, then lowered and fed forward through the material so that binding is unlikely. Sliding compound miter saws are relatively portable, easy to set up, because they cut from above it is not necessary to adjust blade depth for different thicknesses of work piece and, like any bench machine, repeat cuts are very easy. Most saws have an adjustable scale plate for table swiveling with positive stops at commonly used angles, also, there are usually adjustable stops at 90 and 45 degrees for head tilting allowing easy and very accurate adjustment of the saw. Table swiveling in both directions is universal but most saws allow head tilting only in one direction, although some saws allow head tilting in both directions
15.
Plasma cutting
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Plasma cutting is a process that cuts through electrically conductive materials by means of an accelerated jet of hot plasma. Typical materials cut with a plasma torch include steel, Stainless steel, aluminum, brass and copper, Plasma cutting is often used in fabrication shops, automotive repair and restoration, industrial construction, and salvage and scrapping operations. Due to the speed and precision cuts combined with low cost. This is accomplished by a gas which is blown through a focused nozzle at high speed toward the work piece. An electrical arc is formed within the gas, between an electrode near or integrated into the gas nozzle and the work piece itself. The electrical arc ionizes some of the gas, thereby creating a conductive channel of plasma. As electricity from the cutter torch travels down this plasma it delivers sufficient heat to melt through the work piece. At the same time, much of the high velocity plasma and compressed gas blow the hot molten metal away, Plasma cutting is an effective means of cutting thin and thick materials alike. Hand-held torches can cut up to 38 mm thick steel plate. Since plasma cutters produce a hot and very localized cone to cut with. Plasma cutting grew out of plasma welding in the 1960s, and emerged as a productive way to cut sheet metal. It had the advantages over traditional metal against metal cutting of producing no metal chips, giving accurate cuts, early plasma cutters were large, somewhat slow and expensive and, therefore, tended to be dedicated to repeating cutting patterns in a mass production mode. These CNC plasma cutting machines were, however, generally limited to cutting patterns and parts in flat sheets of steel, proper eye protection and face shields are needed to prevent eye damage called arc eye as well as damage from debris. It is recommended to use green lens shade #5, OSHA recommends a shade 8 for arc current less than 300, but notes that These values apply where the actual arc is clearly seen. Experience has shown that lighter filters may be used when the arc is hidden by the workpiece, lincoln Electric, a manufacturer of plasma cutting equipment, says, Typically a darkness shade of #7 to #9 is acceptable. Plasma cutters use a number of methods to start the arc, in some units, the arc is created by putting the torch in contact with the work piece. Some cutters use a voltage, high frequency circuit to start the arc. This method has a number of disadvantages, including risk of electrocution, difficulty of repair, spark gap maintenance, Plasma cutters working near sensitive electronics, such as CNC hardware or computers, start the pilot arc by other means
16.
Water jet cutter
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Waterjet cutting is often used during fabrication of machine parts. It is the method when the materials being cut are sensitive to the high temperatures generated by other methods. Waterjet cutting is used in industries, including mining and aerospace, for cutting, shaping. These early applications were at a low pressure and restricted to soft materials like paper, Waterjet technology evolved in the post-war era as researchers around the world searched for new methods of efficient cutting systems. In 1958, Billie Schwacha of North American Aviation developed a system using ultra-high-pressure liquid to cut hard materials and this system used a 100,000 psi pump to deliver a hypersonic liquid jet that could cut high strength alloys such as PH15-7-MO stainless steel. Used as a honeycomb laminate on the Mach 3 North American XB-70 Valkyrie, while not effective for the XB-70 project, the concept was valid and further research continued to evolve waterjet cutting. In 1962, Philip Rice of Union Carbide explored using a pulsing waterjet at up to 50,000 psi to cut metals, stone, research by S. J. Leach and G. L.002 inches that operated at pressures up to 70,000 psi. High-pressure vessels and pumps became affordable and reliable with the advent of steam power, by the mid-1800s, steam locomotives were common and the first efficient steam-driven fire engine was operational. By the turn of the century, high-pressure reliability improved, with research leading to a sixfold increase in boiler pressure. Most high-pressure pumps at this time, though, operated around 500–800 psi, high-pressure systems were further shaped by the aviation, automotive, and oil industries. Aircraft manufacturers such as Boeing developed seals for hydraulically boosted control systems in the 1940s, higher pressures in hydraulic systems in the oil industry also led to the development of advanced seals and packing to prevent leaks. These advances in technology, plus the rise of plastics in the post-war years. The invention of Marlex by Robert Banks and John Paul Hogan of the Phillips Petroleum company required a catalyst to be injected into the polyethylene, mcCartney Manufacturing Company in Baxter Springs, Kansas, began manufacturing these high-pressure pumps in 1960 for the polyethylene industry. Flow Industries then combined the high-pressure pump research with their waterjet nozzle research, while cutting with water is possible for soft materials, the addition of an abrasive turned the waterjet into a modern machining tool for all materials. This began in 1935 when the idea of adding an abrasive to the stream was developed by Elmo Smith for the liquid abrasive blasting. The March 1984 issue of the Mechanical Engineering magazine showed more details and materials cut with AWJ such as titanium, aluminum, glass, dr. Mohamed Hashish, was awarded a patent on forming AWJ in 1987. Current work on AWJ nozzles is on micro abrasive waterjet so cutting with jets smaller than 0.015 inches in diameter can be commercialized. By January,1985, that system was being run 24 hours a day producing titanium parts for the B-1B largely at Rockwells North American Aviation facility in Newark, as waterjet cutting moved into traditional manufacturing shops, controlling the cutter reliably and accurately was essential
17.
Broaching (metalworking)
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Broaching is a machining process that uses a toothed tool, called a broach, to remove material. There are two types of broaching, linear and rotary. In linear broaching, which is the common process, the broach is run linearly against a surface of the workpiece to effect the cut. Linear broaches are used in a machine, which is also sometimes shortened to broach. In rotary broaching, the broach is rotated and pressed into the workpiece to cut an axis symmetric shape, a rotary broach is used in a lathe or screw machine. In both processes the cut is performed in one pass of the broach, which makes it very efficient, Broaching is used when precision machining is required, especially for odd shapes. Commonly machined surfaces include circular and non-circular holes, splines, keyways, typical workpieces include small to medium-sized castings, forgings, screw machine parts, and stampings. Even though broaches can be expensive, broaching is usually favored over other processes used for high-quantity production runs. Broaches are shaped similar to a saw, except the height of the teeth increases over the length of the tool, moreover, the broach contains three distinct sections, one for roughing, another for semi-finishing, and the final one for finishing. Broaching is a machining process because it has the feed built into the tool. The profile of the surface is always the inverse of the profile of the broach. The rise per tooth, also known as the step or feed per tooth, determines the amount of material removed, the broach can be moved relative to the workpiece or vice versa. Because all of the features are built into the broach no complex motion or skilled labor is required to use it. A broach is effectively a collection of single-point cutting tools arrayed in sequence, cutting one after the other, the process depends on the type of broaching being performed. Surface broaching is very simple as either the workpiece is moved against a stationary surface broach, the process begins by clamping the workpiece into a special holding fixture, called a workholder, which mounts in the broaching machine. The broaching machine elevator, which is the part of the machine moves the broach above the workholder. Once through, the broaching machines puller, essentially a hook, the elevator then releases the top of the pilot and the puller pulls the broach through the workpiece completely. The workpiece is then removed from the machine and the broach is raised back up to reengage with the elevator, the broach usually only moves linearly, but sometimes it is also rotated to create a spiral spline or gun-barrel rifling
18.
Burr (cutter)
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Burrs are small cutting tools used in die grinders, rotary tools, or dental drills. The name may be considered appropriate when their head is compared to a bur or their teeth are compared to a metal burr. Burrs are an analog to files that cut linearly. They are also in many ways comparable to endmills and to router bits, however, there is substantial overlap in the use and toolpath control of these various classes of cutters, and in the outcomes accomplished with them. For example, endmills can be used in routers, and burrs can be used like endmills in milling by CNC or manual machine tools, in fact, burrs are often used in CNC machining centers for removing burrs after a machining process. To maintain the surface speed and cutting conditions, burrs are rotated at high speed. The cutters shown in the image are made from tungsten carbide, hard metal or ceramic workpieces cannot flex beyond the cutting edges, so the tools remove material from them. This characteristic makes them suitable for dentistry, as the tool will grind the hard enamel of teeth, yet leaves soft mouth tissues unharmed if the tool should erroneously touch them
19.
Chisel
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The handle and blade of some types of chisel are made of metal or of wood with a sharp edge in it. Chiselling use involves forcing the blade into some material to cut it, the driving force may be applied by pushing by hand, or by using a mallet or hammer. In industrial use, a ram or falling weight drives a chisel into the material. A gouge, one type of chisel, serves - particularly in woodworking, woodturning, gouges most frequently produce concave surfaces. A gouge typically has a U-shaped cross-section, chisel comes from the Old French cisel, modern ciseau, Late Latin cisellum, a cutting tool, from caedere, to cut. Chisels have a variety of uses. Many types of chisel have been devised, each suited to its intended use. Different types of chisel may be constructed differently, in terms of blade width or length, as well as shape. They may have a wooden or plastic handle attached using a tang or socket, woodworking chisels range from small hand tools for tiny details, to large chisels used to remove big sections of wood, in roughing out the shape of a pattern or design. Typically, in woodcarving, one starts with a larger tool, one of the largest types of chisel is the slick, used in timber frame construction and wooden shipbuilding. There are many types of woodworking chisels used for specific purposes, such as, Butt chisel, short chisel with beveled sides and straight edge for creating joints. Carving chisels, used for designs and sculpting, cutting edges are many, such as gouge, skew, parting, straight, paring. Corner chisel, resembles a punch and has an L-shaped cutting edge, cleans out square holes, mortises and corners with 90 degree angles. Bevel edge chisel, can get into acute angles with its bevelled edges, 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 chisel, except it has a longer. Slick, a large chisel driven by pressure, never struck. Mortise chisel, thick, rigid blade with cutting edge and deep, slightly tapered sides to make mortises. Paring chisel, has a long blade ideal for cleaning grooves, skew chisel, has a 60 degree cutting angle and is used for trimming and finishing
20.
Counterbore
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A counterbore is a cylindrical flat-bottomed hole that enlarges another coaxial hole, or the tool used to create that feature. A counterbore hole is used when a fastener, such as a socket head cap screw, is required to sit flush with or below the level of a workpieces surface. Whereas a counterbore is an enlargement of a smaller coaxial hole. A spotface often takes the form of a very shallow counterbore, as mentioned above, the cutters that produce counterbores are often also called counterbores, sometimes, to avoid ambiguity, the term counterbore cutter is used instead. A counterbore hole is used when the head of a fastener. For a spotface, material is removed from a surface to make it flat and smooth, spotfacing is usually required on workpieces that are forged or cast. A tool referred to as a counterbore is typically used to cut the spotface, only enough material is removed to make the surface flat. A counterbore is also used to create a surface for a fastener head on a non-perpendicular surface. If this is not feasible then a self-aligning nut may be required, by comparison, a countersink makes a conical hole and is used to seat a flathead screw. Standards exist for the sizes of counterbores, especially for fastener head seating areas and these standards can vary between corporations and between standards organizations. This is in contrast to the ASME Y14. 5-2009 definition of a spotface, counterbores are made with standard dimensions for a certain size of screw or are produced in sizes that are not related to any particular screw size. Counterbores matched to specific screw sizes generally have integral pilots that fit the hole diameter associated with a particular screw size. Counterbores that are not related to a specific screw size are designed to accept a removable pilot, the pilot matters little when running the cutter in a milling setup where rigidity is assured and hole center location is already achieved via X-Y positioning. The uppermost counterbore tools shown in the image are the same device, the smaller top item is an insert, the middle shows another three-fluted counterbore insert, assembled in the holder. The shank of this holder is a Morse taper, although there are other machine tapers that are used in the industry, the lower counterbore is designed to fit into a drill chuck, and being smaller, is economical to make as one piece. Countersink Degarmo, E. Paul, Black, J T. Kohser, materials and Processes in Manufacturing, Wiley, ISBN 0-471-65653-4
21.
Countersink
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A countersink is a conical hole cut into a manufactured object, or the cutter used to cut such a hole. A common use is to allow the head of a bolt or screw. A countersink may also be used to remove the burr left from a drilling or tapping operation thereby improving the finish of the product, the basic geometry of a countersink inherently can be applied to the plunging applications described above and also to other milling applications. Therefore, countersinks overlap in form, function, and sometimes name with chamfering endmills, regardless of the name given to the cutter, the surface being generated may be a conical chamfer or a beveled corner for the intersection of two planes. A countersink may be used in tools, such as drills, drill presses, milling machines. A Dan Martin Style zero flute countersink is a tool with a cutting edge provided by a hole that goes through the side of the cone. The intersection of the hole and cone form the edge on the tool. The cone is not truly symmetrical as it is essential that the cone retreats away from the edge as the tool rotates providing clearance. If this does not occur the cutting edge will lack clearance and this clearance is referred to as cutting relief. The fluted countersink cutter is used to provide a heavy chamfer in the entrance to a drilled hole and this may be required to allow the correct seating for a countersunk-head screw or to provide the lead in for a second machining operation such as tapping. Countersink cutters are manufactured with six common angles, which are 60°, 82°, 90°, 100°, 110°, or 120°, with the two most common of those being 82° and 90°. Countersunk-head screws that follow the Unified Thread Standard very often have an 82° angle, throughout the aerospace industry, countersunk fasteners typically have an angle of 100°. A back countersink, also known as an inserted countersink, is a two piece countersink used on tough to reach areas. One component is a rod that is inserted into the hole in the workpieces, the other component is the cutter. This is comparable to types of back- machining, such as back-spotfacing, back-boring, back-counterboring, back-milling. The common theme is accomplishing machining operations on the far side of the workpiece from the spindle face and this reduces setup time and frustration in several ways. It can often be difficult to avoid chatter when cutting with countersink cutters, as usual in machining, the shorter and more rigid the setup, the better. Better-quality fluted countersink cutters sometimes have the flutes at an irregular pitching and this variation in pitching reduces the chance of the cutting edges setting up a harmonic action and leaving an undulated surface
22.
End mill
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An end mill is a type of milling cutter, a cutting tool used in industrial milling applications. It is distinguished from the bit in its application, geometry. While a drill bit can only cut in the axial direction, end mills are used in milling applications such as profile milling, tracer milling, face milling, and plunging. Each category may be divided by specific application and special geometry. It is becoming common for traditional solid end mills to be replaced by more cost-effective inserted cutting tools. End mills are sold in imperial and metric shank and cutting diameters. In the USA, metric is readily available, but it is used in some machine shops and not others, in Canada, due to the countrys proximity to the US. In Asia and Europe, metric diameters are standard, a variety of grooves, slots, and pockets in the work-piece may be produced from a variety of tool bits. Common tool bit types are, square end cutters, ball end cutters, t-slot cutters, square end cutters can mill square slots, pockets, and edges. Ball end cutters mill radiused slots or fillets, t-slot cutters mill exactly that, T-shaped slots. Shell end cutters are used for flat surfaces and for angle cuts. There are variations of these types as well. There are four angles of each cutting tool, end cutting edge angle, axial relief angle, radial relief angle. Depending on the material being milled, and what task should be performed, different tool types and geometry may be used. For instance, when milling a material like aluminium, it may be advantageous to use a tool with very deep, polished flutes, when machining a tough material such as stainless steel, however, shallow flutes and a squared-off cutting edge will optimize material removal and tool life. A wide variety of materials are used to produce the cutting tools, carbide inserts are the most common because they are good for high production milling. High speed steel is used when a special tool shape is needed. Ceramics inserts are typically used in high speed machining with high production, Diamond inserts are typically used on products that require tight tolerances, typically consisting of high surface qualities
23.
File (tool)
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A file is a tool used to remove fine amounts of material from a workpiece. It is common in woodworking, metalworking, and other similar trade, most are hand tools, made of a case hardened steel bar of rectangular, square, triangular, or round cross-section, with one or more surfaces cut with sharp, generally parallel teeth. A narrow, pointed tang is common at one end, to which a handle may be fitted, a rasp is a form of file with distinct, individually cut teeth used for coarsely removing large amounts of material. Files have also developed with abrasive surfaces, such as natural or synthetic diamond grains or silicon carbide, allowing removal of material that would dull or resist metal. Relatedly, lapping is also ancient, with wood and beach sand offering a natural pair of lap. The Disston authors state, To abrade, or file, ancient man used sand, grit, coral, bone, fish skin, the Bronze Age and the Iron Age had various kinds of files and rasps. Archaeologists have discovered rasps made from bronze in Egypt, dating back to the years 1200–1000 BC, archaeologists have also discovered rasps made of iron used by the Assyrians, dating back to the 7th Century BC. During the Middle Ages files were already advanced, thanks to the extensive talents of blacksmiths. By the 11th century, there already existed hardened files that would seem quite modern even to todays eyes. For example, in the 13th century, ornamental iron work at Paris was done skillfully with the aid of files, but the process was a secret known only to a master craftsman. The Disston authors state, It was not until the fourteenth century, however, that those who practiced art in ironwork began to use tools, besides heat. This statement could mislead in the sense that stoning and lapping have never been rare activities among humans, but by the late Middle Ages, however, the transition was extensive. The Disston authors mention Nuremberg, Sheffield, and Remscheid as leading centers of production for files as well as tools in general, the activity in Remscheid reflects the metalworking spirit of the Rhine-Ruhr region in general rather than representing a single village of geniuses in isolation. Most files of the period were smithed by hand in a sequence in which the iron was forged, then the teeth were cut with a chisel, among the drawings of Leonardo da Vinci is a sketch of a machine tool for the cutting of files. Prior to the industrialization of machining and the development of parts during the 19th century. Component parts were roughly shaped by forging, casting, and by primitive machining operations and these components were then individually hand-fit for assembly by careful and deliberate filing. The potential precision of fitting is much higher than generally assumed. Locks, clocks, and firearms were manufactured in this way for centuries before the Industrial Revolution, machining in the mid-19th century was heavily dependent on filing, because milling practice was slowly evolving out of its infancy
24.
Hand scraper
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A hand scraper is a single-edged tool used to scrape metal from a surface. This may be required where a surface needs to be trued, corrected for fit to a part, needs to retain oil. Surface plates were made by scraping. Three raw cast surface plates, a scraper and a quantity of bearing blue were all that was required in the way of tools. The scraper in the center of the image is a three corner scraper and is used to deburr holes or the internal surface of bush type bearings. Bushes are typically made from bronze or a white metal, the scraper pictured at the bottom is a curved scraper. It has a curve in its profile and is also suitable for bush bearings. One advantage of scraping is the ability to take the tool to the workpiece, the person that scrapes is called a hand. It is done by using a precision surface such as a surface plate or a straight edge as a standard. The standard is coated with a thin coating of a material such as Prussian blue. The work piece and standard are touched together by gravity alone and these high spots are scraped off and the process repeated until there is an even spread of high spots which total about 60% or more of the surface area. Coarse scraping gives a surface with 5-10 points per square inch while fine scraping yields 24-36 points per square inch. If desired the surface can then be “Frosted”, a surface prepared in this way is superior in overall accuracy to any prepared by machining or grinding operations, although lapping can equal or exceed it over small distances. Grinding and machining stresses the metal thermally and mechanically, scraping and lapping do not, with precision ground surfaces, any oil film applied to the surface will lack the means to adhere to the surface, especially between two mating parts of exceptional finish. The oil film will be swept away leaving nothing but bare metal, carefully scraping the surface will leave the original high quality surface intact, but provide many shallow depressions where the oil film can maintain its depth and surface tension. When scraping is used for this purpose it is more accurately called frosting, spotting or flaking as opposed to fully scraping an accurate surface, typically a scraped surface is scraped to highly accurate flatness and then frosting is applied over it for oil retention. It is claimed to stop the so-called stick-slip phenomenon where a member might move in a jerky fashion rather than moving smoothly, allowing vibration. Such frosting will definitely increase oil retention but will also drastically reduce bearing area, there is no possibility of achieving hydrodynamic bearing performance on normal sliding machine ways. The velocity is far too low, most of the time the ways will run under boundary lubrication conditions while at the highest speeds it might achieve mixed lubrication
25.
Milling cutter
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Milling cutters are cutting tools typically used in milling machines or machining centres to perform milling operations. They remove material by their movement within the machine or directly from the cutters shape, milling cutters come in several shapes and many sizes. There is also a choice of coatings, as well as rake angle, shape, Several standard shapes of milling cutter are used in industry today, which are explained in more detail below. Flutes / teeth, The flutes of the bit are the deep helical grooves running up the cutter. The tooth cuts the material, and chips of material are pulled up the flute by the rotation of the cutter. There is almost always one tooth per flute, but some cutters have two teeth per flute, often, the words flute and tooth are used interchangeably. Milling cutters may have one to many teeth, with 2,3 and 4 being most common. Typically, the teeth a cutter has, the more rapidly it can remove material. So, a 4-tooth cutter can remove material at twice the rate of a 2-tooth cutter, helix angle, The flutes of a milling cutter are almost always helical. If the flutes were straight, the tooth would impact the material at once, causing vibration and reducing accuracy. Setting the flutes at an angle allows the tooth to enter the material gradually, typically, finishing cutters have a higher rake angle to give a better finish. Center cutting, Some milling cutters can drill straight down through the material and this is because the teeth of some cutters do not go all the way to the centre of the end face. However, these cutters can cut downwards at an angle of 45 degrees or so, a roughing cutter may have serrated teeth for breaking the chips of material into smaller pieces. These teeth leave a surface behind. A finishing cutter may have a large number teeth for removing material carefully, however, the large number of flutes leaves little room for efficient swarf removal, so they are less appropriate for removing large amounts of material. Coatings, The right tool coatings can have an influence on the cutting process by increasing cutting speed and tool life. Polycrystalline diamond is a hard coating used on cutters which must withstand high abrasive wear. A PCD coated tool may last up to 100 times longer than an uncoated tool, however the coating cannot be used at temperatures above 600 degrees C, or on ferrous metals
26.
Reamer
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A reamer is a type of rotary cutting tool used in metalworking. Precision reamers are designed to enlarge the size of a previously formed hole by a small amount, there are also non-precision reamers which are used for more basic enlargement of holes or for removing burrs. The process of enlarging the hole is called reaming, there are many different types of reamer and they may be designed for use as a hand tool or in a machine tool, such as a milling machine or drill press. A typical reamer consists of a set of straight or helical cutting edges along the length of a cylindrical body. Each cutting edge is ground at a angle and with a slight undercut below the cutting edge. Reamers must combine both hardness in the edges, for long life, and toughness, so that the tool does not fail under the normal forces of use. They should only be used to small amounts of material. This ensures a long life for the reamer and a finish to the hole. The spiral may be clockwise or counter-clockwise depending on usage, for example, a tapered hand reamer with a clockwise spiral will tend to self feed as it is used, possibly leading to a wedging action and consequent breakage. A counter-clockwise spiral is therefore preferred even though the reamer is still turned in the clockwise direction, for hand tools, the shank end is usually a square drive, intended for use with the same type of wrench used to turn a tap for the cutting of screw threads. The geometry of a hole drilled in metal by a twist drill may not be accurate enough, the planned difference between the drill diameter and the reamer diameter is called an allowance. The allowance should be <0.2 mm for soft materials, larger allowances can damage the reamer. The drilled hole should not be enlarged by more than 5% of the drilled diameter, drilling followed by reaming generally produces hole geometry and finish that is as close to theoretical perfection as possible. An adjustable hand reamer can cover a range of sizes. They are generally referenced by a letter which equates to a size range, the disposable blades slide along a tapered groove. The act of tightening and loosening the restraining nuts at each end varies the size that may be cut, the absence of any spiral in the flutes restricts them to light usage as they have a tendency to chatter. They are also restricted to usage in unbroken holes, if a hole has an axial split along it, such as a split bush or a clamping hole, each straight tooth will in turn drop into the gap causing the other teeth to retract from their cutting position. This also gives rise to chatter marks and defeats the purpose of using the reamer to size a hole, a straight reamer is used to make only a minor enlargement to a hole
27.
Shear (sheet metal)
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There are many types of shears used to shear sheet metal. A bench shear, also known as a shear, is a bench mounted shear with a compound mechanism to increase the mechanical advantage. It is usually used for cutting rough shapes out of medium-sized pieces of sheet metal, for the small shear, it mostly designed for a wide field of applications. Light weight and easy efficient operation, yet very sturdy in construction, the cutting blades fitted are carefully and accurately ground to give easy, clean quick cuts, and free of burrs. These special features help the operators save a great deal of their energy, but some shearing machines can cut sheet bar and flat bar up to 10mm. It is electrically welded together to make it a sturdy stable unit capable to withstand highest stresses due to heavy duty usage, the footplates are reinforced with bracing angles so that they give firm stability to the shear. The machine used is called a shear, power shear. The machine may be powered, less commonly hand powered. It works by first clamping the material with a ram, a moving blade then comes down across a fixed blade to shear the material. For larger shears the moving blade may be set on an angle or rocked in order to shear the material progressively from one side to the other, setting the blade on an angle decreases the amount of force required, but increases the stroke. A5 degree shear angle decreases the force by about 20%, the amount of energy used is still the same. The moving blade may also be inclined 0.5 to 2. 5°, called the rake angle, however, raking the blade compromises the squareness of the edge. The machine consists of a table, work-holding device, upper and lower blades. The shear table is the part of the machinery that the workpiece rests on while being sheared, the work-holding device is used to hold the workpiece in place and keep it from moving or buckling while under stress. The upper and lower blades are the piece of machinery that actually do the cutting, the design of press tools is an engineering compromise. A sharp edge, strength, and durability are ideal, but a sharp edge is not very strong or durable, typical workpiece materials include aluminum, brass, bronze, and mild steel because of their outstanding shearability ratings. Stainless steel is not sheared as often due to its tendencies to work-harden, other geometric possibilities include the squaring shear, angle shear, bow-tie shear and bar shear. All of these have different uses and are all used regularly in certain manufacturing fields
28.
Tipped tool
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A tipped tool generally refers to any cutting tool where the cutting edge consists of a separate piece of material, either brazed, welded or clamped on to a separate body. Common materials for tips include cemented carbide, polycrystalline diamond, tools that are commonly tipped include, milling cutters, tool bits, and saw blades. The advantage of tipped tools is only a small insert of the material is needed to provide the cutting ability. The small size makes manufacturing of the easier than making a solid tool of the same material. This also reduces cost because the tool holder can be made of a less-expensive, in some situations a tipped tool is better than its solid counterpart because it combines the toughness of the tool holder with the hardness of the insert. In other situations this is less optimal, because the joint between the tool holder and the insert reduces rigidity. However, these tools may still be used because the overall cost savings is still greater, inserts are removable cutting tips, which means they are not brazed or welded to the tool body. They are usually indexable, meaning that they can be rotated or flipped without disturbing the overall geometry of the tool. This saves time in manufacturing by allowing fresh cutting edges to be presented periodically without the need for grinding, setup changes. A wiper insert is a used in a milling machine or a lathe. It is designed for cutting, to give a smooth surface on the surface being cut. It uses special geometry to give a finish on the workpiece at a higher-than-normal feedrate. Wiper inserts generally have an area in contact with the workpiece. This makes them unsuitable for fragile workpieces, inserts used for turning and milling are often numbered according to ISO standard 1832. This standard aims to make the naming, specifying and ordering of inserts a simple, consistent and this standard takes into account both metric and imperial systems of units, although certain elements differ for each unit system
29.
Tool bit
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A tool bit is a non-rotary cutting tool used in metal lathes, shapers, and planers. Such cutters are often referred to by the set-phrase name of single-point cutting tool. The cutting edge is ground to suit a particular machining operation, the ground tool bit is held rigidly by a tool holder while it is cutting. Back rake is to control the direction of the chip. It also helps counteract the pressure against the tool from the work by pulling the tool into the work. Side Rake along with back rake controls the flow and partly counteracts the resistance of the work to the movement of the cutter. Brass for example requires a back and side rake of 0 degrees while aluminum uses a rake of 35 degrees. Nose Radius makes the finish of the cut smoother as it can overlap the previous cut and eliminate the peaks, having a radius also strengthens the tip, a sharp point being quite fragile. All the other angles are for clearance in order that no part of the tool besides the actual cutting edge can touch the work, the front clearance angle is usually 8 degrees while the side clearance angle is 10-15 degrees and partly depends on the rate of feed expected. The Rake angles on the top of the tool need not be precise in order to cut but to cut efficiently there will be an angle for back. Originally, all tool bits were made of carbon tool steels with the appropriate hardening and tempering. Since the introductions of high-speed steel, sintered carbide, ceramic and diamond cutters, most tool bits today are made of HSS, cobalt steel, or carbide. Carbide, ceramics and diamond, having higher hardness than HSS, because these materials are more expensive and brittler than steel, typically the body of the cutting tool is made of steel, and a small cutting edge made of the harder material is attached. The cutting edge is either screwed or clamped on, or brazed on to a steel shank. Almost all high-performance cutting tools use indexable inserts, there are several reasons for this. First of all, at the very high cutting speeds and feeds supported by these materials, economics are also important, inserts are made symmetrically so that when the first cutting edge is dull they can be rotated, presenting a fresh cutting edge. Some inserts are made so that they can be flipped over. There are many types of inserts, some for roughing, some for finishing, others are made for specialized jobs like cutting threads or grooves
30.
Brake (sheet metal bending)
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A brake is a metalworking machine that allows the bending of sheet metal. A cornice brake only allows for simple bends and creases, while a box-and-pan brake also allows one to form box and it is also known as a bending machine or bending brake or in Britain as a sheet metal folder or just a folder. The brake consists of a surface onto which the material is placed. This clamping action may be manual, automatic or operated using a foot pedal, the front, gate-like, plate of the machine is hinged and may be lifted, forcing the material extended over a straight edge to bend to follow the plate. The bends can be to any angle up to a limit of about 120 degrees. If the area to be bent is narrow enough, a bend can be made by inserting the bend under the clamping bar. A cornice brake has a solid clamping bar, the width of the machine, thus, it can only make straight bends. After bending, a box or pan form is completed by screw, solder, weld, rivet. This is a brake, usually much smaller than cornice or box-and-pan brakes. Typically, a handle both clamps the workpiece and makes the bend, in a single motion, but the depth is usually much less than what a cornice or box-and-pan brake can handle. This is a complex tool that forms predetermined bends by clamping the workpiece between a matching punch and die
31.
Die (manufacturing)
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A die is a specialized tool used in manufacturing industries to cut or shape material mostly using a press. Like molds, dies are generally customized to the item they are used to create, products made with dies range from simple paper clips to complex pieces used in advanced technology. Forming dies are made by tool and die makers and put into production after mounting into a press. The die is a block that is used for forming materials like sheet metal. For the vacuum forming of sheet only a single form is used. Vacuum forming is considered a simple molding thermoforming process but uses the principles as die forming. The workpiece may pass through several stages using different tools or operations to obtain the final form, the main components for die tool sets are, Die block – This is the main part that all the other parts are attached to. Punch plate – This part holds and supports the different punches in place, blank punch – This part along with the blank die produces the blanked part. Pierce punch – This part along with the pierce die removes parts from the finished part. Stripper plate – This is used to hold the material down on the blank/pierce die, pilot – This will help to place the sheet accurately for the next stage of operation. Guide, back gauge, or finger stop – These parts are all used to make sure that the material being worked on always goes in the position, within the die. Setting block – This part is used to control the depth that the punch goes into the die, Blanking dies – See blanking punch Pierce die – See pierce punch. Shank – used to hold in the presses and it should be aligned and situated at the center of gravity of the plate. Processes, Blanking, A blanking die produces a piece of material by cutting the desired shape in one operation. The finished part is referred to as a blank, generally a blanking die may only cut the outside contour of a part, often used for parts with no internal features. Three benefits to die blanking are, Accuracy, a properly sharpened die, with the correct amount of clearance between the punch and die, will produce a part that holds close dimensional tolerances in relationship to the parts edges. Since the part is blanked in one operation, the edges of the part produces a uniform appearance as opposed to varying degrees of burnishing from multiple operations. Due to the compression of the blanking process, the end result is a flat part that may retain a specific level of flatness for additional manufacturing operations
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English wheel
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The English wheel, in Britain also known as a wheeling machine, is a metalworking tool that enables a craftsperson to form compound curves from flat sheets of metal such as aluminium or steel. The process of using an English wheel is known as wheeling and it is a forming machine that works by surface stretching and is related in action to panel beating processes. English wheel production is at its highest in low-volume sports car production and this cost is defrayed across a larger production run, but a stamping press is limited to only one model of panel per set of dies. The English wheel model shown is manually operated, but when used on thicker sheet metals such as for ship hulls the machine may be powered, the machine is shaped like a large, closed letter C. At the ends of the C, there are two wheels, the wheel on the top is called the rolling wheel, while the wheel on the bottom is called the anvil wheel. The anvil wheel usually has a smaller radius than the rolling wheel, although larger machines exist, the rolling wheel is usually 8 cm wide or less, and usually 25 cm in diameter, or less. The rolling wheel is flat in cross section, while the wheel is domed. The depth of the C-shaped frame is called the throat, the largest machines have throat sizes of 120 cm, while smaller machines have throat sizes of about 60 cm. The C stands vertically and is supported by a frame, the throat size usually determines the largest size of metal sheet that the operator can place in the machine and work easily. On some machines, the operator can turn the top wheel and it may move with a hydraulic jack on machines designed for steel plate, or a jackscrew on machines designed for sheet metals. As the material thins, the operator must adjust the pressure to compensate, frame designs are the most significant element of this simple device. For the most part wheels have changed little since the 19th century. The early English machines, such as Edwards, Kendrick, Brown, Boggs and these wheels, made during the 19th Century, had Babbitt metal plain bearings, making them difficult to push and pull the metal through when operated at high pressures. Later, when ball bearings came into use, the became more suitable for hard and thick material. Despite the advantages of cast iron, it has less than half the stiffness of steel, steel frames made of solid flame-cut plate, or frames built-up of cut-and-welded plates, are common designs. Tube-framed machines are reasonably-priced and are either as kit-built machines. The stiffest tubular frames have a fully triangulated external bracing truss and they are most effective on thinner or softer materials, such as 20 ga steel or.063 aluminum. Cast frame machines, like the one pictured, are still available, a properly equipped machine has an assortment of anvil wheels
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Hydraulic press
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A hydraulic press is a device using a hydraulic cylinder to generate a compressive force. It uses the equivalent of a mechanical lever, and was also known as a Bramah press after the inventor, Joseph Bramah. He invented and was issued a patent on this press in 1795, as Bramah installed toilets, he studied the existing literature on the motion of fluids and put this knowledge into the development of the press. The hydraulic press depends on Pascals principle, the pressure throughout a system is constant. Only small-diameter tubing is needed if the pump is separated from the press cylinder, Pascals law, Pressure on a confined fluid is transmitted undiminished and acts with equal force on equal areas and at 90 degrees to the container wall. A fluid, such as oil, is displaced when either piston is pushed inward, since the fluid is incompressible, the volume that the small piston displaces is equal to the volume displaced by the large piston. This causes a difference in the length of displacement, which is proportional to the ratio of areas of the heads of the pistons, therefore, the small piston must be moved a large distance to get the large piston to move significantly. The distance the piston will move is the distance that the small piston is moved divided by the ratio of the areas of the heads of the pistons. This is how energy, in the form of work in case, is conserved. Work is force applied over a distance, and since the force is increased on the larger piston, bramahs basic idea is also exploited in hydroforming. Hydraulic presses are used for forging, clinching, moulding, blanking, punching, deep drawing. The room featured in Fermats Room has a similar to that of a hydraulic press. Boris Artzybasheff also created a drawing of a press, in which the press was created out of the shape of a robot. In 2015, the Hydraulic Press Channel, a YouTube channel solely dedicated to crushing objects with a press, was created. The channel is owned and operated by Lauri Vuohensilta from Tampere, Finland
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Machine press
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A forming press, commonly shortened to press, is a machine tool that changes the shape of a workpiece by the application of pressure. Good for general-purpose work in the mechanic shop, machine shop, garage or basement shops. Typically 1 to 30 tons of pressure, depending on size, classed with engine hoists and engine stands in many tool catalogs. A press brake is a type of machine press that bends sheet metal into shape. A good example of the type of work a press brake can do is the backplate of a computer case, other examples include brackets, frame pieces and electronic enclosures. Some press brakes have CNC controls and can form parts with accuracy to a fraction of a millimetre, bending forces can range up to 3,000 tons. A punch press is used to form holes, a screw press is also known as a fly press. A stamping press is a press used to shape or cut metal by deforming it with a die. It generally consists of a frame, a bolster plate. Capping presses form caps from rolls of foil at up to 660 per minute. A servomechanism press, also known as a press or a electro press, is a press driven by an AC servo motor. The torque produced is converted to a linear force via a ball screw, pressure and position are controlled through a load cell and an encoder. The main advantage of a press is its low energy consumption. When stamping, its really about maximizing energy as opposed to how the machine can deliver tonnage, up until recently, the way to increase tonnage between the die and workpiece on a mechanical press was through bigger machines with bigger motors. The press style used is in correlation to the end product. Press types are straightside, BG, geared, gap, OBI, hydraulic and mechanical presses are classified by the frame the moving elements are mounted on. The most common are the gap-frame, also known as C-frame, a straightside press has vertical columns on either side of the machine and eliminates angular deflection. A C-frame allows easy access to the die area on three sides and require less floor space, a type of gap-frame, the OBI pivots the frame for easier scrap or part discharge
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Punch press
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A punch press is a type of machine press used to cut holes in material. It can be small and manually operated and hold one simple die set, or be large, CNC operated, with a multi-station turret and hold a much larger. Punch presses are large machines with either a C type frame, C type presses have a bed plate which is used to lock the die bottom bolster. For locking the die, T bolts are used and so this plate contain T - slots into which t- bolts are slid in and these slots are placed diagonally and with a slot horizontal to the longer side of the plate, is the general practice. The top of the tool butted against a sliding ram with a clamping system which accommodates only a particular diameter of a threaded cylindrical member called the shank of the tool. The bottom portion of the tool is locked to the bottom bed plate, top and bottom portions of the tool are generally guided by suitable pillar and bush assemblies, which gives safety to the punching elements of the tool. Generally the tool is placed slightly above the bottom bed plate by providing two parallel blocks accurately ground to the same size and this is a necessary action since many tools, scrap is discharged through the bottom element of the tool, not necessarily in the centre of the tool. The scrap or the blank come out from the die at different places and these have to be taken out horizontally from between the parallels placed. Otherwise they get accumulated inside the tool itself and cause damage to the tool. In very heavy presses with higher tonnage, The sliding ram has also a plate with T slots for locking the top plate of the tool. In such cases the threaded cylinder called shank is not attached to the tool, the clamps are either mechanical or air operated varieties. Turret type punch press machines have a table or bed with brushes or rollers to allow the metal workpiece to traverse with low friction. Brushes are used where scratches on the workpiece must be minimized, in a production environment a 30-ton press is mostly the machine used today. The tonnage needed to cut and form the material is well known, according to the requirement the tonnage may even go up to 2000 to 2500 ton presses. A die set consists of a set of punches and dies which, the punches and dies are removable, with the punch being attached to the ram during the punching process. The ram moves up and down in a linear motion. The main bed of most machines is called the X Axis with the Y Axis being at right angles to that and allowed to traverse under CNC control. Dependent on the size of the machine, the beds, and the metal workpiece weight
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Screw press
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A screw press is a type of machine press in which the ram is driven up and down by a screw. The screw shaft can be driven by a handle or a wheel and it works by using a coarse screw to convert the rotation of the handle or drive-wheel into a small downward movement of greater force. The overhead handle usually incorporates balls as flyweights, the weights helps to maintain the momentum and thrust of the tool to make it easier to operate. The screw press was first invented and used by the Romans in the first century A. D and it was used primarily in wine and olive oil production. The screwpress was also used in Gutenbergs printing press in the mid-15th century, a press is a metalworking machine tool used to shape or cut metal by deforming it with a die. It is frequently used to punch holes in metal in one operation. If used as a punch, the tool consists of a punch. Both are usually machined and then hardened. The material is introduced between the punch and die, and the machine operated, the punch will cut through the material in one movement by shearing it. The punch and die may be of any desired shape, so odd shaped holes, if used as a forging tool the dies can be many different shapes varying from flat to various shapes that will mold the metal to the desired configuration. A fly press is a type of press in which the screw shaft is driven by a flywheel or a pair of fly weights at the ends of a bar. The wheel can either be cranked by hand or driven by a using a friction coupling. The wheel is weighted so its momentum will maintain the motion of the shaft
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Stamping press
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A stamping press is a metalworking machine tool used to shape or cut metal by deforming it with a die. In simple terms, a press is the modern day equivalent of a hammer. The only difference is that precision made male and female dies that dictate the shape of the part are between the hammer and anvil. A press has a plate, and a ram. The bolster plate is mounted on top of the bed and is a large block of metal upon which the bottom portion of a die is clamped. Large presses may be equipped die cushions integrated in the plate to apply blank holder or counter draw forces. This is necessary when a single acting press is used for deep drawing, the ram / slide is the moving or reciprocating member that the upper die is mounted to. Ram or Slide guidance is an element to assure long die life between die maintenance. Different types of slide guides are available,4 point V-Gibs or 6 point square gibs on smaller presses and 8 point full length slide guides on larger straight side frame presses, the vertical motion of the slide acts like a hammer to an anvil. When presses are used manually, where an operator is loading and unloading parts, extreme caution should be used, standard modes of operation with up to date safe press controls are OFF-INCH-SINGLE STROKE & CONTINUOUS modes which can be selected via a keyed mode selector switch. Special modes of operation include, MICRO INCH-SSD/SINGLE ON DEMAND & CSD/CONTINUOUS ON DEMAND. Micro Inch is normally used for die set up near the BDC / Bottom Dead Center, CSD Continuous on Demand is normally used when press are used in roll form lines or irregular stroking is required when punching holes in large panel with gag feed dies. The nature of drive system determines the force progression during the rams stroke, mechanical presses have a full tonnage rating point above BDC / Bottom Dead Center, normal full tonnage rating points are.187.25 &.5. Hence a mechanical press has a curve and should be operated within the press capacity limits. Link Motion mechanical is yet another option, this provides a slow down near BDC / bottom dead center for soft touch tooling. This link feature can improve die life and reduce reverse-snap thru tonnage for blanking operations, on the contrary, Hydraulic Presses do not have a tonnage curve and can produce full tonnage at any point in the stroke. The trade off is speed, a press is much faster when compared to hydraulic. On the other hand, Hydraulic Presses are much more practical for deep forming or drawing or parts or when dwell time at the bottom is desired
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Clamp (tool)
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A clamp is a fastening device used to hold or secure objects tightly together to prevent movement or separation through the application of inward pressure. There are many types of available for many different purposes. Some are temporary, as used to position components while fixing them together, in the field of animal husbandry, using a clamp to attach an animal to a stationary object is known as rounded clamping. A physical clamp of this type is used to refer to an obscure investment banking term. Anything that performs the action of clamping may be called a clamp and these clamps are used to position components temporarily for various tasks, Band clamp or web clamp Bar clamp, F-clamp or sliding clamp Bench clamp The bench forms the fixed jaw. Forked clamp stainless steel for ST ground glass joints with/without setscrew, sizes for, ST14,19,24,29 änd 45. Gluing and Clamping, A Woodworker’s Handbook
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Combination square
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A combination square is a tool used for multiple purposes in woodworking, stonemasonry and metalworking. It is composed of a blade and one or more interchangeable heads that may be affixed to it. The most common head is the standard or square head which is used to lay out or check right, invented in 1883 by Laroy S. Starrett, the combination square continues to be a commonplace tool in home workshops, construction jobsites and metalworking. Measuring angles — A combination square can reliably measure 90° and 45° angles, the 45° angle is used commonly in creating miter joints. Determining flatness — When working with wood the first step is to designate a reference surface on a board which is known as the face side, the rest of the workpiece is measured from the face side Measuring the center of a circular bar or dowel. Perform this action at two locations and the lines will approximate the center of the bar. Protractor head allows angles to be set and measured between the base and ruler, a rudimentary level for approximating level surfaces is incorporated in the protractor and also the 45° holder. By moving and setting the head, it can be used as a gauge or to transfer dimensions. Marking the work surface, with the included Scribe Point stored in a hole in the Square Base. It is used to find the center of the round jobs, in woodworking, the starting raw material is neither flat nor square, however, the end product such as a table must be flat and have corners and legs which are square. In metalworking, it is useful for a variety of layout. When used correctly, a high degree of precision can be achieved. One use would be setting large items at the angle in machine vices
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Drift pin
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A drift pin is not used as a punch in the traditional sense of the term. A drift is constructed as a rod, with the hammer acting on the large end of the taper. The tapered end of a punch is placed into the semi-aligned bolt holes of two separate components, and then driven into the hole. As it is driven in, the forces the two components into alignment, allowing for easy insertion of the fastener. Unlike most punches, force should never be applied to the tip of drift pin, drift pins are especially useful for aligning fastener holes in structural steel members. Spud wrenches used for assembling trusses and steel beams have tapered handles to use as drift pins
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Hacksaw
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A hacksaw is a fine-toothed saw, originally and principally made for cutting metal. They can also cut various materials, such as plastic and wood, for example, plumbers and electricians often cut plastic pipe. There are hand saw versions and powered versions, most hacksaws are hand saws with a C-shaped frame that holds a blade under tension. Such hacksaws have a handle, usually a pistol grip, with pins for attaching a narrow disposable blade, the frames may also be adjustable to accommodate blades of different sizes. A screw or other mechanism is used to put the blade under tension. Panel hacksaws forgo the frame and instead have a metal body. These saws are no commonly available, but hacksaw blade holders enable standard hacksaw blades to be used similarly to a keyhole saw or pad saw. Power tools including nibblers, jigsaws, and angle grinders fitted with metal-cutting blades, on hacksaws, as with most frame saws, the blade can be mounted with the teeth facing toward or away from the handle, resulting in cutting action on either the push or pull stroke. In normal use, cutting vertically downwards with work held in a bench vice, some frame saws, including Fret Saws and Piercing Saws, have their blades set to be facing the handle because they are used to cut by being pulled down against a horizontal surface. While saws for cutting metal had been in use for years, significant improvements in longevity and efficiency were made in the 1880s by George N. Clemson. Inc of Middletown, New York, United States, Clemson conducted tests which involved changing the dimensions, shapes of teeth, styles of set, and variable heat treatments of blades. Clemson claimed enormous improvements to the ability of blades and built a major industrial operation manufacturing hacksaw blades sold under the trade name Star Hack Saw. In 1898, Clemson was granted US Patent 601947, which details various improvements in the hacksaw, blades are available in standardized lengths,10 or 12 inches for a standard hand hacksaw. Junior hacksaws are 6 inches long, powered hacksaws may use large blades in a range of sizes, or small machines may use the same hand blades. The pitch of the teeth can be anywhere from fourteen to thirty-two teeth per inch for a hand blade, the blade chosen is based on the thickness of the material being cut, with a minimum of three teeth in the material. As hacksaw teeth are so small, they are set in a wave set, hacksaw blades are normally quite brittle, so care needs to be taken to prevent brittle fracture of the blade. Early blades were of steel, now termed low alloy blades. They avoided breakage, but also wore out rapidly, except where cost is a particular concern, this type is now obsolete
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Hammer
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A hammer is a tool or device that delivers a blow to an object. Most hammers are hand tools used to drive nails, fit parts, forge metal, hammers vary in shape, size, and structure, depending on their purposes. Hammers are basic tools in many trades, the usual features are a head and a handle. Although most hammers are hand tools, powered versions exist, they are known as powered hammers, types of power hammer include steam hammers and trip hammers, often for heavier uses, such as forging. Some hammers have other names, such as sledgehammer, mallet, the term hammer also applies to devices that deliver blows, such as the hammer of a firearm or the hammer of a piano or the hammer ice scraper. The use of simple hammers dates to about 2,600,000 BCE when various shaped stones were used to strike wood, bone, or other stones to break them apart and shape them. Stones attached to sticks with strips of leather or animal sinew were being used as hammers with handles by about 30,000 BCE during the middle of the Paleolithic Stone Age. The hammers archeological record shows that it may be the oldest tool for which evidence exists of its early existence. A traditional hand-held hammer consists of a head and a handle, fastened together by means of a special wedge made for the purpose, or by glue. This two-piece design is used, to combine a dense metallic striking head with a non-metallic mechanical-shock-absorbing handle. If wood is used for the handle, it is often hickory or ash, rigid fiberglass resin may be used for the handle, this material does not absorb water or decay, but does not dissipate shock as well as wood. A loose hammer head is hazardous because it can fly off the handle when in use. Wooden handles can often be replaced when worn or damaged, specialized kits are available covering a range of sizes and designs. Some hammers are one-piece designs made primarily of a single material, a one-piece metallic hammer may optionally have its handle coated or wrapped in a resilient material such as rubber, for improved grip and reduced user fatigue. The hammer head may be surfaced with a variety of materials, including brass, bronze, wood, plastic, rubber, some hammers have interchangeable striking surfaces, which can be selected as needed or replaced when worn out. A large hammer-like tool is a maul, a wood- or rubber-headed hammer is a mallet, the essential part of a hammer is the head, a compact solid mass that is able to deliver a blow to the intended target without itself deforming. The impacting surface of the tool is usually flat or slightly rounded, some upholstery hammers have a magnetized face, to pick up tacks. In the hatchet, the hammer head may be secondary to the cutting edge of the tool
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Machinist square
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A machinist square or engineers square is the metalworkers equivalent of a try square. It consists of a steel blade inserted and either welded or pinned into a body at an angle of 90°. Usually a small notch is present at the corner of the square. This prevents small particles from accumulating at the juncture and affecting the squares reading, in use, the body is aligned against the one edge of the object and the blade is presented to the end or body of the object. If the end is being checked, then a light source behind the square will show any mismatch between the blade of the square and the end of the object. The purpose of action is to check for squareness or to mark out the body of the workpiece. Machinist squares can have an error of no greater than 0.0002 in/in. Squares must be checked for accuracy. The four disk method is one way to verify overall squareness, however, it cannot detect bent blades. There are several different International or National standards that Engineers Squares are manufactures to, also under these standards there are different grades of accuracy that a square can be made and sold to. It usually relates to a deviation of X amount of blade lean Vs height of measurement usually done at the top of the blade. This also assumes that the blade and body widths are both perfectly parallel making for a true reading along the length and inside and outside the square. Typically there are A or B grade squares made and sold, B grade being perfectly serviceable for most general use where accuracy is required in a workshop situation. The simplest method of checking a low grade square for accuracy is to draw a line across a board with a flat face, then flip the square over 180 degrees and check if the blade aligns with the line just drawn. Any error is multiplied by two and appears as a wedge or taper, the ultimate method of mechanically calibrating a try square or similar is with a cylindrical master square sitting on a granite or cast iron surface plate that is flat. By nature of their construction a cylindrical master square cannot help, a square to be tested can be presented to the master and feeler gauges used with a source of light behind the gap to get a reading of deviation. Other methods of calibration are available and this can involve modern technology by using a CMM for example, or a vertical machining center with a dial indicator in it
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Needlegun scaler
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A needlegun scaler, needle scaler or needle-gun is a tool used to remove rust, mill scale, and old paint from metal surfaces. The tool is used in applications as diverse as home repair, automotive repair. A needle gun has a set of very fine chisels known as needles, the tool forces these needles against a work surface at variable speeds up to around 5,000 times per minute. Different models offer choices of number of needles, operating speed, many models use compressed air, although electrical needle-guns do exist. In a pneumatic unit, compressed air forces a piston forwards and backwards and this movement causes the needles to move back and forth against the work surface. The needle gun has advantages over other scaling tools and its main advantage is that the needles automatically adjust themselves to contours, making the tool a good choice for cleaning irregular surfaces. A needle gun can clean an area to bare metal in seconds and it is recommended that before needlegunning, a surface should be prepared by removing oil, grease, dirt, chemicals and water-soluble contaminants. This can be done with solvents or with a combination of detergent, then, the needle gun is used to remove rust, loose scale, and paint, leaving bare metal. It is used most effectively by holding it at a 45° angle to the work surface and it is recommended that an area no larger than six to eight inches be cleared at once. Two to three passes over an area is generally sufficient to clean it, then the process is repeated until the desired area is completed. Prior to painting, it is desirable to feather any edges between metal and old paint and it is also important to check the surface for oil deposited during chipping, and if necessary, clean the area with solvents. Since bare metal surfaces will flash rust soon after exposure to the atmosphere, if flash rusting occurs prior to coating, further chipping, cleaning and sanding may be necessary. Abrasive blasting Corrosion Wire brush Miller, Jason, chapter 7, Submarine Forces Afloat Painting and Preservation Guidelines for Non-Nuclear Spaces and Components. Joint Fleet Maintenance Manual - Rev A Change 7, -- CHAP7 LINK NO LONGER WORKS Naval Education and Training Command. #13, The Repair and Thermal Upgrading of Historic Steel Windows, video of needle-gunning rust Battleship Texas Restoration Manual Safety while removing paint Schematic and parts list for Jet Chisel JT-20
