1.
Wood shaper
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The spindle may be raised and lowered relative to the shapers table, and rotates between 3,000 and 10,000 rpm, with stock running along a vertical fence. Wood shaper cutter heads typically have three blades, and turn at 1/2 to 1/8th the speed of smaller, much less expensive two-bladed bits used on a wood router. Adapters are sold allowing a shaper to drive router bits, a compromise on several levels, as are router tables, cost-saving adaptations of hand-held routers mounted to comparatively light-duty dedicated work tables. Shapers feature between 1.5 and 5 hp belt-driven motors, which run more quietly and smoothly than typically 20,000 to 25,000 rpm direct-drive routers. Speed adjustments are made by relocating the belts on a stepped pulley system. The most common form of wood shaper has a spindle, some have horizontal. Some European models variously combine sliding tablesaws, jointers, planers, Shapers can be adapted to perform specialized cuts employing accessories such as sliding tables, tenon tables, tilting arbor, tenoning hoods, and interchangeable spindles. The standard US spindle shaft is 1¼, with 3/4 on small shapers, most spindles are tall enough to accommodate more than one cutter head, allowing rapid tooling changes by raising or lowering desired heads into position. Additional spindles can be fitted with pre-spaced cutter heads when more are needed for a job than fit on one, the primary safety feature on a wood shaper is a guard mounted above the cutter protecting hands and garments from being drawn into its blades. Jigs, fixtures such as hold-downs, and accessories that include featherboards, also help prevent injury and generally result in better cuts. The starter, or fulcrum, pin is a rod which threads into the table a few inches away from the cutter allowing stock to be fed into it in a freehand cut. In addition to aiding productivity and setting a consistent rate of milling and they may be multi-speed, and employ rubber wheels to feed stock past the cutter head. Wood Shapers - Information and resources about wood shapers, particularly older models
2.
Boring (manufacturing)
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In machining, boring is the process of enlarging a hole that has already been drilled, by means of a single-point cutting tool, for example as in boring a gun barrel or an engine cylinder. Boring is used to greater accuracy of the diameter of a hole. Boring can be viewed as the counterpart to turning, which cuts external diameters. There are various types of boring, the boring bar may be supported on both ends, or it may be supported at one end. Backboring is the process of reaching through a hole and then boring on the back side of the workpiece. The first boring machine tool was invented by John Wilkinson in 1775, boring and turning have abrasive counterparts in internal and external cylindrical grinding. Each process is based on the requirements and parameter values of a particular application. The dimensions between the piece and the bit can be changed about two axes to cut both vertically and horizontally into the internal surface. The cutting tool is usually single point, made of M2 and M3 high-speed steel or P10, a tapered hole can also be made by swiveling the head. Boring machines come in a variety of sizes and styles. Boring operations on small workpieces can be carried out on a lathe while larger workpieces are machined on boring mills, workpieces are commonly 1 to 4 metres in diameter, but can be as large as 20 m. Power requirements can be as much as 200 horsepower, cooling of the bores is done through a hollow passageway through the boring bar where coolant can flow freely. Tungsten-alloy disks are sealed in the bar to counteract vibration and chatter during boring, the control systems can be computer-based, allowing for automation and increased consistency. Because boring is meant to decrease the product tolerances on pre-existing holes, first, large length-to-bore-diameters are not preferred due to cutting tool deflection. Next, through holes are preferred over blind holes, interrupted internal working surfaces—where the cutting tool and surface have discontinuous contact—are preferably avoided. The boring bar is the arm of the machine that holds the cutting tool. Because of the factors just mentioned, deep-hole drilling and deep-hole boring are inherently challenging areas of practice that demand special tooling, nevertheless, technologies have been developed that produce deep holes with impressive accuracy. In most cases involve multiple cutting points, diametrically opposed
3.
Electrical discharge machining
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Material is removed from the workpiece by a series of rapidly recurring current discharges between two electrodes, separated by a dielectric liquid and subject to an electric voltage. One of the electrodes is called the tool-electrode, or simply the tool or electrode, while the other is called the workpiece-electrode, the process depends upon the tool and workpiece not making actual contact. This phenomenon is the same as the breakdown of a capacitor, as a result, material is removed from the electrodes. Adding new liquid dielectric in the volume is commonly referred to as flushing. Also, after a current flow, the difference of potential between the electrodes is restored to what it was before the breakdown, so that a new liquid dielectric breakdown can occur, the erosive effect of electrical discharges was first noted in 1770 by English physicist Joseph Priestley. Two Russian scientists, B. R. Butinzky and N. I, lazarenko, were tasked in 1943 to investigate ways of preventing the erosion of tungsten electrical contacts due to sparking. They failed in this task but found that the erosion was more precisely controlled if the electrodes were immersed in a dielectric fluid and this led them to invent an EDM machine used for working difficult-to-machine materials such as tungsten. The Lazarenkos machine is known as an R-C-type machine, after the circuit used to charge the electrodes. Simultaneously but independently, an American team, Harold Stark, Victor Harding, initially constructing their machines from feeble electric-etching tools, they were not very successful. But more powerful sparking units, combined with automatic spark repetition, Stark, Harding, and Beavers machines were able to produce 60 sparks per second. Later machines based on their design used vacuum tube circuits that were able to produce thousands of sparks per second, the wire-cut type of machine arose in the 1960s for the purpose of making tools from hardened steel. The tool electrode in wire EDM is simply a wire, to avoid the erosion of material from the wire causing it to break, the wire is wound between two spools so that the active part of the wire is constantly changing. The earliest numerical controlled machines were conversions of punched-tape vertical milling machines, the first commercially available NC machine built as a wire-cut EDM machine was manufactured in the USSR in 1967. Machines that could optically follow lines on a master drawing were developed by David H. Dulebohns group in the 1960s at Andrew Engineering Company for milling and grinding machines, master drawings were later produced by computer numerical controlled plotters for greater accuracy. A wire-cut EDM machine using the CNC drawing plotter and optical line follower techniques was produced in 1974, dulebohn later used the same plotter CNC program to directly control the EDM machine, and the first CNC EDM machine was produced in 1976. Electrical discharge machining is a machining method primarily used for hard metals or those that would be difficult to machine with traditional techniques. EDM typically works with materials that are conductive, although methods for machining insulating ceramics with EDM have also been proposed. EDM can cut intricate contours or cavities in pre-hardened steel without the need for treatment to soften and re-harden them
4.
Machine tool
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A machine tool is a machine for shaping or machining metal or other rigid materials, usually by cutting, boring, grinding, shearing, or other forms of deformation. Machine tools employ some sort of tool that does the cutting or shaping, all machine tools have some means of constraining the workpiece and provide a guided movement of the parts of the machine. Thus the relative movement between the workpiece and the tool is controlled or constrained by the machine to at least some extent. The precise definition of the machine tool varies among users. While all machine tools are machines that help people to make things, today machine tools are typically powered other than by human muscle, used to make manufactured parts in various ways that include cutting or certain other kinds of deformation. With their inherent precision, machine tools enabled the production of interchangeable parts. In this view of the definition, the term, arising at a time when all tools up till then had been hand tools and this lathe produced screw threads out of wood and employed a true compound slide rest. The mechanical toolpath guidance grew out of various concepts, First is the spindle concept itself. The machine slide, which has many forms, such as dovetail ways, box ways, Machine slides constrain tool or workpiece movement linearly. If a stop is added, the length of the line can also be accurately controlled, tracing, which involves following the contours of a model or template and transferring the resulting motion to the toolpath. Cam operation, which is related in principle to tracing but can be a step or two removed from the traced elements matching the reproduced elements final shape. For example, several cams, no one of which matches the desired output shape. Abstractly programmable toolpath guidance began with mechanical solutions, such as in musical box cams, later, electromechanical solutions and soon electronic solutions were added, leading to numerical control and computer numerical control. The value that machine tools added to these human talents is in the areas of rigidity, accuracy and precision, efficiency, as an example, it is physically possible to make interchangeable screws, bolts, and nuts entirely with freehand toolpaths. But it is practical to make them only with machine tools. In the 1930s, the U. S. National Bureau of Economic Research referenced the definition of a tool as any machine operating by other than hand power which employs a tool to work on metal. The narrowest colloquial sense of the reserves it only for machines that perform metal cutting—in other words. These processes are a type of deformation that produces swarf, thus presses are usually included in the economic definition of machine tools
5.
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
6.
Machining
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Machining is any of various processes in which a piece of raw material is cut into a desired final shape and size by a controlled material-removal process. Exactly what the part of the definition implies can vary. Machining is a part of the manufacture of metal products, but it can also be used on materials such as wood, plastic, ceramic. A person who specializes in machining is called a machinist, a room, building, or company where machining is done is called a machine shop. Machining can be a business, a hobby, or both, much of modern-day machining is carried out by computer numerical control, in which computers are used to control the movement and operation of the mills, lathes, and other cutting machines. The precise meaning of the term machining has evolved over the past one, in the 18th century, the word machinist simply meant a person who built or repaired machines. This persons work was mostly by hand, using processes such as the carving of wood. At the time, millwrights and builders of new kinds of engines, such as James Watt or John Wilkinson, the noun machine tool and the verb to machine did not yet exist. Around the middle of the 19th century, the words were coined as the concepts that they described evolved into widespread existence. Therefore, during the Machine Age, machining referred to the machining processes, such as turning, boring, drilling, milling, broaching, sawing, shaping, planing, reaming. In current usage, the term machining without qualification usually implies the traditional machining processes, the three principal machining processes are classified as turning, drilling and milling. Other operations falling into miscellaneous categories include shaping, planing, boring, broaching and sawing, turning operations are operations that rotate the workpiece as the primary method of moving metal against the cutting tool. Lathes are the machine tool used in turning. Milling operations are operations in which the tool rotates to bring cutting edges to bear against the workpiece. Milling machines are the machine tool used in milling. Drilling operations are operations in which holes are produced or refined by bringing a rotating cutter with cutting edges at the lower extremity into contact with the workpiece, drilling operations are done primarily in drill presses but sometimes on lathes or mills. Burnishing is an example of a miscellaneous operation, burnishing produces no swarf but can be performed at a lathe, mill, or drill press. An unfinished workpiece requiring machining will need to have some material cut away to create a finished product, a finished product would be a workpiece that meets the specifications set out for that workpiece by engineering drawings or blueprints
7.
Lathe
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Lathes are used in woodturning, metalworking, metal spinning, thermal spraying, parts reclamation, and glass-working. Lathes can be used to shape pottery, the design being the potters wheel. Most suitably equipped metalworking lathes can also be used to produce most solids of revolution, plane surfaces, ornamental lathes can produce three-dimensional solids of incredible complexity. The workpiece is held in place by either one or two centers, at least one of which can typically be moved horizontally to accommodate varying workpiece lengths. Other work-holding methods include clamping the work about the axis of rotation using a chuck or collet, or to a faceplate, using clamps or dogs. Examples of objects that can be produced on a lathe include candlestick holders, gun barrels, cue sticks, table legs, bowls, baseball bats, musical instruments, crankshafts, and camshafts. The lathe is an ancient tool, dating at least to ancient Egypt and known to be used in Assyria, the lathe was very important to the Industrial Revolution. It is known as the mother of machine tools, as it was the first machine tool that lead to the invention of other machine tools, the origin of turning dates to around 1300 BCE when the Ancient Egyptians first developed a two-person lathe. One person would turn the work piece with a rope while the other used a sharp tool to cut shapes in the wood. Ancient Rome improved the Egyptian design with the addition of a turning bow, in the Middle Ages a pedal replaced hand-operated turning, allowing a single person to rotate the piece while working with both hands. The pedal was usually connected to a pole, often a straight-grained sapling, the system today is called the spring pole lathe. Spring pole lathes were in use into the early 20th century. An important early lathe in the UK was the boring machine that was installed in 1772 in the Royal Arsenal in Woolwich. It was horse-powered and allowed for the production of more accurate. One of the key characteristics of this machine was that the workpiece was turning as opposed to the tool, henry Maudslay who later developed many improvements to the lathe worked at the Royal Arsenal from 1783 being exposed to this machine in the Verbruggen workshop. During the Industrial Revolution, mechanized power generated by water wheels or steam engines was transmitted to the lathe via line shafting, allowing faster and easier work, metalworking lathes evolved into heavier machines with thicker, more rigid parts. Between the late 19th and mid-20th centuries, individual electric motors at each lathe replaced line shafting as the power source, today manually controlled and CNC lathes coexist in the manufacturing industries. A lathe may or may not have legs, which sit on the floor, a lathe may be small and sit on a workbench or table, not requiring a stand
8.
Helix
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A helix is a type of smooth space curve, i. e. a curve in three-dimensional space. It has the property that the tangent line at any point makes a constant angle with a line called the axis. Examples of helices are coil springs and the handrails of spiral staircases, a filled-in helix – for example, a spiral ramp – is called a helicoid. Helices are important in biology, as the DNA molecule is formed as two intertwined helices, and many proteins have helical substructures, known as alpha helices, the word helix comes from the Greek word ἕλιξ, twisted, curved. Helices can be either right-handed or left-handed, handedness is a property of the helix, not of the perspective, a right-handed helix cannot be turned to look like a left-handed one unless it is viewed in a mirror, and vice versa. Most hardware screw threads are right-handed helices, the alpha helix in biology as well as the A and B forms of DNA are also right-handed helices. The Z form of DNA is left-handed, the pitch of a helix is the height of one complete helix turn, measured parallel to the axis of the helix. A double helix consists of two helices with the axis, differing by a translation along the axis. A conic helix may be defined as a spiral on a conic surface, an example is the Corkscrew roller coaster at Cedar Point amusement park. A circular helix, has constant band curvature and constant torsion, a curve is called a general helix or cylindrical helix if its tangent makes a constant angle with a fixed line in space. A curve is a general helix if and only if the ratio of curvature to torsion is constant, a curve is called a slant helix if its principal normal makes a constant angle with a fixed line in space. It can be constructed by applying a transformation to the frame of a general helix. Some curves found in nature consist of multiple helices of different handedness joined together by transitions known as tendril perversions, in mathematics, a helix is a curve in 3-dimensional space. The following parametrisation in Cartesian coordinates defines a particular helix, Probably the simplest equations for one is x = cos , y = sin , z = t. As the parameter t increases, the point traces a right-handed helix of pitch 2θ and radius 1 about the z-axis, in cylindrical coordinates, the same helix is parametrised by, r =1, θ = t, h = t. A circular helix of radius a and slope b/a is described by the following parametrisation, another way of mathematically constructing a helix is to plot the complex-valued function exi as a function of the real number x. The value of x and the real and imaginary parts of the function value give this plot three real dimensions, except for rotations, translations, and changes of scale, all right-handed helices are equivalent to the helix defined above. The equivalent left-handed helix can be constructed in a number of ways, in music, pitch space is often modeled with helices or double helices, most often extending out of a circle such as the circle of fifths, so as to represent octave equivalency
9.
North America
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North America is a continent entirely within the Northern Hemisphere and almost all within the Western Hemisphere. It can also be considered a subcontinent of the Americas. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the west and south by the Pacific Ocean, and to the southeast by South America and the Caribbean Sea. North America covers an area of about 24,709,000 square kilometers, about 16. 5% of the land area. North America is the third largest continent by area, following Asia and Africa, and the fourth by population after Asia, Africa, and Europe. In 2013, its population was estimated at nearly 565 million people in 23 independent states, or about 7. 5% of the worlds population, North America was reached by its first human populations during the last glacial period, via crossing the Bering land bridge. The so-called Paleo-Indian period is taken to have lasted until about 10,000 years ago, the Classic stage spans roughly the 6th to 13th centuries. The Pre-Columbian era ended with the migrations and the arrival of European settlers during the Age of Discovery. Present-day cultural and ethnic patterns reflect different kind of interactions between European colonists, indigenous peoples, African slaves and their descendants, European influences are strongest in the northern parts of the continent while indigenous and African influences are relatively stronger in the south. Because of the history of colonialism, most North Americans speak English, Spanish or French, the Americas are usually accepted as having been named after the Italian explorer Amerigo Vespucci by the German cartographers Martin Waldseemüller and Matthias Ringmann. Vespucci, who explored South America between 1497 and 1502, was the first European to suggest that the Americas were not the East Indies, but a different landmass previously unknown by Europeans. In 1507, Waldseemüller produced a map, in which he placed the word America on the continent of South America. He explained the rationale for the name in the accompanying book Cosmographiae Introductio, for Waldseemüller, no one should object to the naming of the land after its discoverer. He used the Latinized version of Vespuccis name, but in its feminine form America, following the examples of Europa, Asia and Africa. Later, other mapmakers extended the name America to the continent, In 1538. Some argue that the convention is to use the surname for naming discoveries except in the case of royalty, a minutely explored belief that has been advanced is that America was named for a Spanish sailor bearing the ancient Visigothic name of Amairick. Another is that the name is rooted in a Native American language, the term North America maintains various definitions in accordance with location and context. In Canadian English, North America may be used to refer to the United States, alternatively, usage sometimes includes Greenland and Mexico, as well as offshore islands
