A lathe ( / l eɪ ð / ) is a machine tool that rotates a workpiece about an axis of rotation to perform various operations such as cutting , sanding , knurling , drilling , deformation , facing , threading and turning , with tools that are applied to the workpiece to create an object with symmetry about that axis.
112-499: Lathes are used in woodturning , metalworking , metal spinning , thermal spraying , reclamation, and glass-working. Lathes can be used to shape pottery , the best-known design being the Potter's wheel . Most suitably equipped metalworking lathes can also be used to produce most solids of revolution , plane surfaces and screw threads or helices . Ornamental lathes can produce three-dimensional solids of incredible complexity. The workpiece
224-512: A catch , where the tool bites suddenly and aggressively into the wood in an uncontrolled manner. These risky practices can exert extremely large forces upon the wood, the tool, the lathe, and the operator. The wood could fracture or tear free from the lathe. In lathe accidents, tools are often torn from the operator's hand and thrown in unexpected directions. Particular care is required for wooden shapes that are not circular, such as off-center work, and for bowls with wings or square rims. Portions of
336-412: A collet inserted into the spindle and secured either by a draw-bar, or by a collet closing cap on the spindle. Suitable collets may also be used to mount square or hexagonal workpieces. In precision toolmaking work such collets are usually of the draw-in variety, where, as the collet is tightened, the workpiece moves slightly back into the headstock, whereas for most repetition work the dead length variety
448-429: A pattern for foundries , often from wood, but also plastics. A patternmaker's lathe looks like a heavy wood lathe, often with a turret and either a leadscrew or a rack and pinion to manually position the turret . The turret is used to accurately cut straight lines. They often have a provision to turn very large parts on the other end of the headstock, using a free-standing toolrest. Another way of turning large parts
560-409: A turner , and the skills needed to use the tools were traditionally known as turnery . In pre-industrial England, these skills were sufficiently difficult to be known as "the mysteries of the turners' guild." The skills to use the tools by hand, without a fixed point of contact with the wood, distinguish woodturning and the wood lathe from the machinist's lathe, or metal-working lathe . Items made on
672-414: A "compound rest" that attach to the lathe bed and allows the tool to be clamped in place and moved by a screw or lever feed. Graver tools are generally supported by a T-rest, not fixed to a cross slide or compound rest. The work is usually held in a collet, but high-precision 3 and 6-jaw chucks are also commonly employed. Common spindle bore sizes are 6 mm, 8 mm and 10 mm. The term WW refers to
784-434: A "crash" occurs when the machine moves in such a way that is harmful to the machine, tools, or parts being machined, sometimes resulting in bending or breakage of cutting tools, accessory clamps, vises, and fixtures, or causing damage to the machine itself by bending guide rails, breaking drive screws, or causing structural components to crack or deform under strain. A mild crash may not damage the machine or tools but may damage
896-549: A CNC machine in the form of a sequential program of machine control instructions such as G-code and M-code, and then executed. The program can be written by a person or, far more often, generated by graphical computer-aided design (CAD) or computer-aided manufacturing (CAM) software. In the case of 3D printers, the part to be printed is "sliced" before the instructions (or the program) are generated. 3D printers also use G-Code. CNC offers greatly increased productivity over non-computerized machining for repetitive production, where
1008-420: A CNC workflow is still in setup. In modern CNC systems, the design of a mechanical part and its manufacturing program are highly automated. The part's mechanical dimensions are defined using CAD software and then translated into manufacturing directives by CAM software. The resulting directives are transformed (by " post processor " software) into the specific commands necessary for a particular machine to produce
1120-539: A bench or table, but offer such features as tool holders and a screw-cutting gear train are called hobby lathes, and larger versions, "bench lathes" - this term also commonly applied to a special type of high-precision lathe used by toolmakers for one-off jobs. Even larger lathes offering similar features for producing or modifying individual parts are called "engine lathes". Lathes of these types do not have additional integral features for repetitive production, but rather are used for individual part production or modification as
1232-405: A cantilevered tool-rest. At one end of the bed (almost always the left, as the operator faces the lathe) is a headstock. The headstock contains high-precision spinning bearings. Rotating within the bearings is a horizontal axle, with an axis parallel to the bed, called the spindle . Spindles are often hollow and have an interior Morse taper on the spindle nose (i.e., facing to the right / towards
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#17328699250971344-404: A clean cut because the wood passes at great speed. Sharpening is usually accomplished with the aid of mechanical devices such as powered sharpening wheels and abrasives. This sharpening process requires either skill of the craftsman, or one of the many available sharpening jigs, which facilitate maintaining a specific bevel on the tool. As with any mechanical sharpening method, overheating or blueing
1456-458: A collection in Philadelphia with over 1,000 objects from international artists as well as a research library and gallery. Other turners have chosen an artisan-based focus on traditional work, custom work, and the pleasure of studio practice. Complex forms made on a wood lathe develop from surprisingly few types of cuts: parting, planing, bead, cove, and hollowing. Parting separates the wood from
1568-438: A common component of most hobby CNC tools. Instead, most hobby CNC tools simply rely on the assumed accuracy of stepper motors that rotate a specific number of degrees in response to magnetic field changes. It is often assumed the stepper is perfectly accurate and never missteps, so tool position monitoring simply involves counting the number of pulses sent to the stepper over time. An alternate means of stepper position monitoring
1680-401: A computer are CNC lathes . Lathes with the spindle mounted in a vertical configuration, instead of horizontal configuration, are called vertical lathes or vertical boring machines. They are used where very large diameters must be turned, and the workpiece (comparatively) is not very long. A lathe with a tool post that can rotate around a vertical axis, so as to present different tools towards
1792-552: A cup, collet, or scroll chuck to hold a tenon on the workpiece which will be removed in the finished product. The wood can also be screwed or glued to a faceplate—a strong disk that is threaded to mount on the headstock's spindle. The use of a chuck or faceplate allows the woodturner to forego tailstock support for the rotating wood. This type of secure holding system is essential for hollowing bowls or hollow forms. Turning tools are generally made from carbon steel , high-speed steel (HSS), and more recently tungsten carbide . Comparing
1904-464: A cycle will involve a crash. Although such simulation is not new, its accuracy and market penetration are changing considerably because of computing advancements. Within the numerical systems of CNC programming, the code generator can assume that the controlled mechanism is always perfectly accurate, or that precision tolerances are identical for all cutting or movement directions. While the common use of ball screws on most modern NC machines eliminates
2016-403: A hardened steel center, which is used to support long thin shafts while turning, or to hold drill bits for drilling axial holes in the work piece. Many other uses are possible. Metalworking lathes have a carriage (comprising a saddle and apron) topped with a cross-slide, which is a flat piece that sits crosswise on the bed and can be cranked at right angles to the bed. Sitting atop the cross slide
2128-707: A large box as a safety measure (with safety glass in the doors to permit the operator to monitor the machine's function), often with additional safety interlocks to ensure the operator is far enough from the working piece for safe operation. Most new CNC systems built today are 100% electronically controlled. CNC-like systems are used for any process that can be described as movements and operations. These include laser cutting , welding , friction stir welding , ultrasonic welding , flame and plasma cutting , bending , spinning, hole-punching, pinning, gluing, fabric cutting, sewing, tape and fiber placement, routing, picking and placing, and sawing. The first CNC machines were built in
2240-462: A lathe dates to the 3rd century BC in ancient Egypt . Pliny later describes the use of a lathe for turning soft stone in his Natural History (Book XXX, Chapter 44). Precision metal-cutting lathes were developed during the lead up to the Industrial Revolution and were critical to the manufacture of mechanical inventions of that period. Some of the earliest examples include a version with
2352-403: A lathe include screws , candlesticks , gun barrels , cue sticks , table legs, bowls , baseball bats , pens , musical instruments (especially woodwind instruments ), and crankshafts . The lathe is an ancient tool. The earliest evidence of a lathe dates back to Ancient Egypt around 1300 BC. There is also tenuous evidence for its existence at a Mycenaean Greek site, dating back as far as
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#17328699250972464-480: A mechanical cutting tool-supporting carriage and a set of gears by Russian engineer Andrey Nartov in 1718 and another with a slide-rest shown in a 1717 edition of the French Encyclopédie . The slide-rest was a particularly important development because it constrains the motion of the cutting tool to generate accurate cylindrical or conical surfaces, unlike earlier lathes that involved freehand manipulation of
2576-425: A piece of material ( metal , plastic , wood, ceramic, stone, or composite) into a specified shape by following coded programmed instructions and without a manual operator directly controlling the machining operation. A CNC machine is a motorized maneuverable tool and often a motorized maneuverable platform, which are both controlled by a computer, according to specific input instructions. Instructions are delivered to
2688-407: A running center is a cup center , which is a cone of metal surrounded by an annular ring of metal that decreases the chances of the workpiece splitting. A circular metal plate with even spaced holes around the periphery, mounted to the spindle, is called an "index plate". It can be used to rotate the spindle to a precise angle, then lock it in place, facilitating repeated auxiliary operations done to
2800-471: A separate flywheel powered a lathe via a drive belt. A master would cut the wood while an apprentice turned the crank on a huge wheel, often several feet in diameter. This was a continuous revolution lathe, which led to adaptation to external power sources such as water, steam, and electricity. This lathe evolved into the 'queen of machine tools' which made it possible to turn parts for other machinery. The Holtzapffels developed ornamental turning lathes from
2912-404: A series of step-down gears. Open-loop control works as long as the forces are kept small enough and speeds are not too great. On commercial metalworking machines, closed-loop controls are standard and required to provide the accuracy, speed, and repeatability demanded. As the controller hardware evolved, the mills themselves also evolved. One change has been to enclose the entire mechanism in
3024-399: A three-dimensional Cartesian coordinate system . This system is a typical plane often seen in mathematics when graphing. This system is required to map out the machine tool paths and any other kind of actions that need to happen in a specific coordinate. Absolute coordinates are what are generally used more commonly for machines and represent the (0,0,0) point on the plane. This point is set on
3136-457: A useful holding device for carving, burning, texturing, coloring, and finishing the form. The wood rotates between the headstock of the lathe which includes the drive mechanism and the tailstock support, which only rotates if its center is 'live' or supported by a rotating holding device. The headstock end may use points or spurs which are driven into the wood. This type of turning is described as 'between centers.' The headstock spindle may also use
3248-409: A wide range of sizes and shapes, depending upon their application. Some common styles are diamond, round, square and triangular. Woodturning Woodturning is the craft of using a wood lathe with hand-held tools to cut a shape that is symmetrical around the axis of rotation. Like the potter's wheel , the wood lathe is a mechanism that can generate a variety of forms. The operator is known as
3360-425: A working height. A lathe may be small and sit on a workbench or table, not requiring a stand. Almost all lathes have a bed, which is almost always a horizontal beam, although CNC lathes commonly have an inclined or vertical beam for a bed to ensure that swarf , or chips, falls free of the bed. Woodturning lathes specialized for turning large bowls often have no bed or tail stock, merely a free-standing headstock and
3472-441: Is 60°. Traditionally, a hard dead center is used together with suitable lubricant in the tailstock to support the workpiece. In modern practice the dead center is frequently replaced by a running center , as it turns freely with the workpiece—usually on ball bearings—reducing the frictional heat, especially important at high speeds. When clear facing a long length of material it must be supported at both ends. This can be achieved by
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3584-454: Is a danger to be avoided as it will ruin the steel's temper, rendering the steel too soft to maintain a sharp edge. When this happens, the blued area must then be ground away to expose fresh steel and the tool must then have the bevel reestablished and the edge re-honed. High-speed steel is not prone to blueing (overheating) whereas carbon steel blues easily, requiring frequent quenching in water or oil to avoid losing temper. When woodturning, it
3696-424: Is a sliding bed, which can slide away from the headstock and thus open up a gap in front of the headstock for large parts. In a metalworking lathe , metal is removed from the workpiece using a hardened cutting tool , which is usually fixed to a solid moveable mounting, either a tool-post or a turret, which is then moved against the workpiece using handwheels or computer-controlled motors. These cutting tools come in
3808-458: Is capable of excellent results in skilled hands. For example, reciprocating bow lathes are still used to turn beads for the Arabian lattice windows called Meshrebeeyeh that so charmed Holtzapffel in the 1880s. Continuous revolution of the workpiece can be human-powered with a treadle wheel, or achieved with water, steam, or electric power. The style of cutting does not have the pause required by
3920-428: Is driven either by foot power from a treadle and flywheel or by a belt or gear drive from a power source such as electric motor or overhead line shafts. In most modern lathes this power source is an integral electric motor, often either in the headstock, to the left of the headstock, or beneath the headstock, concealed in the stand. In addition to the spindle and its bearings, the headstock often contains parts to convert
4032-449: Is duplicating or copying lathe. Some types of them are known as Blanchard lathe, after Thomas Blanchard . This type of lathe was able to create shapes identical to a standard pattern and it revolutionized the process of gun stock making in the 1820s when it was invented. The Hermitage Museum , Russia displays the copying lathe for ornamental turning : making medals and guilloche patterns, designed by Andrey Nartov , 1721. Used to make
4144-416: Is important to wear certain personal protective equipment (PPE). When working with spinning objects, loose clothing should not be worn; all jewelry should be removed; and long hair should be tied back. Since loose rags may also transfer color to the piece, paper towels should be used to avoid snags and accidents. Wood shavings generated during turning will need to be periodically removed. A good way to check
4256-437: Is preferred, as this ensures that the position of the workpiece does not move as the collet is tightened. A soft workpiece (e.g., wood) may be pinched between centers by using a spur drive at the headstock, which bites into the wood and imparts torque to it. A soft dead center is used in the headstock spindle as the work rotates with the centre. Because the centre is soft it can be trued in place before use. The included angle
4368-462: Is the combination of AI , using a large number of sensors , with the goal of achieving flexible manufacturing . EDM can be broadly divided into "sinker" type processes, where the electrode is the positive shape of the resulting feature in the part, and the electric discharge erodes this feature into the part, resulting in the negative shape, and "wire" type processes. Sinker processes are rather slow as compared to conventional machining, averaging on
4480-431: Is usually another slide called a compound rest, which provides two additional axes of motion, rotary and linear. Atop that sits a toolpost, which holds a cutting tool , which removes material from the workpiece. There may or may not be a leadscrew , which moves the cross-slide along the bed. Woodturning and metal spinning lathes do not have cross-slides, but rather have banjos , which are flat pieces that sit crosswise on
4592-461: Is usually 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 dog clutch . Of course, lathes can also complete milling operations by installing special lathe milling fixtures. Examples of objects that can be produced on
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4704-418: Is usually not available, so crash or slip detection is not possible. Commercial CNC metalworking machines use closed-loop feedback controls for axis movement. In a closed-loop system, the controller monitors the actual position of each axis with an absolute or incremental encoder . Proper control programming will reduce the possibility of a crash, but it is still up to the operator and programmer to ensure that
4816-643: The Mary Rose , or sites like the Oseberg burial ship (where the burial was capped by a clay mound), deep wells and other water-logged sites (such as buried pits or ditches). Examples of the latter include 7th century bowls from the island monastery of Iona off western Scotland. Much of this ware was turned from green wood on a spring pole lathe . Finely crafted drinking bowls, known as mazers , were produced in very limited quantities from dry wood, then decorated with silver-gilt central bosses and rims. As early as 1568,
4928-620: The part program . Positioning control is handled using either an open-loop or a closed-loop system. In an open-loop system, communication takes place in one direction only: from the controller to the motor. In a closed-loop system, feedback is provided to the controller so that it can correct for errors in position, velocity, and acceleration, which can arise due to variations in load or temperature. Open-loop systems are generally cheaper but less accurate. Stepper motors can be used in both types of systems, while servo motors can only be used in closed systems. The G & M code positions are all based on
5040-616: The 13th or 14th century BC. Clear evidence of turned artifacts have been found from the 6th century BC: fragments of a wooden bowl in an Etruscan tomb in Northern Italy as well as two flat wooden dishes with decorative turned rims from modern Turkey . During the Warring States period in China , c. 400 BC , the ancient Chinese used rotary lathes to sharpen tools and weapons on an industrial scale. The first known painting showing
5152-464: The 1940s and 1950s, based on existing tools that were modified with motors that moved the tool or part to follow points fed into the system on punched tape . These early servomechanisms were rapidly augmented with analog and digital computers, creating the modern CNC machine tools that have revolutionized machining processes. Now the CNC in the processing manufacturing field has been very extensive, not only
5264-501: The DIY variety, including numerous YouTube videos. The archaeological record of woodturning is limited to illustrations because wood is a fiber prone to rot. Egyptian monuments illustrate a strap used by a helper to rotate the lathe while another worker cut the wood. Early bow lathes and strap lathes were developed and used in Egypt and Rome. The Chinese, Persians, and Arabs had their variations of
5376-519: The U.S., preserved many of the traditional skills of the craft. Between 1975 and 1985, industrial arts teachers, hobbyists, artists, collectors, and tool suppliers developed the symposium format for the exchange of information about the craft. This community was a kind of prototype for the artisan-based maker culture active in the 21st century. The community organizes regional, national, and international symposiums publish journals, and hosts traveling experts at club events. Most publications and DVDs are of
5488-496: The WW (Webster Whitcomb) bed, a truncated triangular prism (found only on 8 and 10 mm watchmakers' lathes); and the continental D-style bar bed (used on both 6 mm and 8 mm lathes by firms such as Lorch and Star). Other bed designs have been used, such as a triangular prism on some Boley 6.5 mm lathes, and a V-edged bed on IME's 8 mm lathes. Smaller metalworking lathes that are larger than jewelers' lathes and can sit on
5600-799: The Webster/Whitcomb collet and lathe, invented by the American Watch Tool Company of Waltham, Massachusetts. Most lathes commonly referred to as watchmakers lathes are of this design. In 1909, the American Watch Tool company introduced the Magnus type collet (a 10-mm body size collet) using a lathe of the same basic design, the Webster/Whitcomb Magnus. (F.W.Derbyshire, Inc. retains the trade names Webster/Whitcomb and Magnus and still produces these collets.) Two bed patterns are common:
5712-457: The X-axis, and all future motions are now invalid, which may result in further collisions with clamps, vises, or the machine itself. This is common in open-loop stepper systems but is not possible in closed-loop systems unless mechanical slippage between the motor and drive mechanism has occurred. Instead, in a closed-loop system, the machine will continue to attempt to move against the load until either
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#17328699250975824-453: The alternative, faceplate dogs may be used to secure the work to the faceplate. A workpiece may be mounted on a mandrel , or circular work clamped in a three- or four-jaw chuck . For irregular shaped workpieces it is usual to use a four jaw (independent moving jaws) chuck. These holding devices mount directly to the lathe headstock spindle. In precision work, and in some classes of repetition work, cylindrical workpieces are usually held in
5936-448: The bed or ways, or to the rest. The swing determines the diametric size of the object which is capable of being turned in the lathe; anything larger would interfere with the bed. This limit is called the swing of the bed. The swing of the rest is the size which will rotate above the rest, which lies upon the bed.") from the notion that the work 'swings' from the centre upon which it is mounted. This makes more sense with odd-shaped work but as
6048-407: The bed) by which work-holding accessories may be mounted to the spindle. Spindles may also have arrangements for work-holding on the left-hand end of the spindle with other tooling arrangements for particular tasks. (i.e., facing away from the main bed) end, or may have a hand-wheel or other accessory mechanism on their outboard end. Spindles are powered and impart motion to the workpiece. The spindle
6160-409: The bed. The position of a banjo can be adjusted by hand; no gearing is involved. Ascending vertically from the banjo is a tool-post, at the top of which is a horizontal tool-rest. In woodturning, hand tools are braced against the tool-rest and levered into the workpiece. In metal spinning, the further pin ascends vertically from the tool-rest and serves as a fulcrum against which tools may be levered into
6272-536: The bow lathe. Early lathe workers would sometimes use their bare feet to hold cutting tools in place while using their hands to power the lathe. Bow lathes continue in use right up to the present day, and much of our information about them comes from watching turners use them. Between 500 and 1500 A.D., turned wooden vessels served as the everyday bowls and cups of most of the population of Europe. Our knowledge of these humble vessels comes from examples preserved in anaerobic environments . These include shipwrecks, such as
6384-436: The capacity of the work that they may hold. Usually large work is held at both ends either using a chuck or other drive in the headstock and a centre in the tailstock. To maximise size, turning between centres allows the work to be as close to the headstock as possible and is used to determine the longest piece the lathe will turn: when the base of the tailstock is aligned with the end of the bed. The distance between centres gives
6496-431: The component and then are loaded into the CNC machine. Since any particular component might require the use of several different tools – drills , saws , touch probes etc. – modern machines often combine multiple tools into a single "cell". In other installations, several different machines are used with an external controller and human or robotic operators that move the component from machine to machine. In either case,
6608-556: The continuous revolution lathe combined with metal-working innovations like the automatic slide rest. These lathes worked from geared patterns to cut designs in hardwoods such as ebony . They were favored as a hobby by European princes, meriting a mention by Tolstoy in War and Peace (1869). Woodturners in London organized into a guild as early as 1310 on Wood Street. By 1347, the Turners Company
6720-414: The cutting edge, generating a thin shaving without chipping or tearing out sections of the wood. Woodturners prefer to use very clean cuts to minimize the time spent with abrasives. When it is necessary to sand the piece, they do so on the lathe, using abrasives held by a hand, in an inertial sander that revolves with the wood's rotation, or with power tools—drills or right-angle drills. The lathe also becomes
6832-423: The drive motor goes into an overload condition or a servo motor fails to get to the desired position. Collision detection and avoidance are possible, through the use of absolute position sensors (optical encoder strips or disks) to verify that motion occurred, or torque sensors or power-draw sensors on the drive system to detect abnormal strain when the machine should just be moving and not cutting, but these are not
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#17328699250976944-418: The drive system is weaker than the machine's structural integrity, then the drive system simply pushes against the obstruction, and the drive motors "slip in place". The machine tool may not detect the collision or the slipping, so for example the tool should now be at 210mm on the X-axis, but is, in fact, at 32mm where it hit the obstruction and kept slipping. All of the next tool motions will be off by −178mm on
7056-426: The grain runs lengthwise along the lathe bed, as if a log were mounted in the lathe. Grain is thus always perpendicular to the direction of rotation under the tool. In bowl turning, the grain runs at right angles to the axis, as if a plank were mounted across the chuck. When a bowl blank rotates, the angle that the grain makes with the cutting tool continually changes between the easy cuts to two places per rotation where
7168-430: The grain. These variable changes may add the illusion of an oval bowl, or draw attention to the features of the wood. Dry wood is necessary for turnings that require precision, as in the fit of a lid to a box, or in forms where pieces are glued together. The character of the wood creates other challenges for the woodturner. Turners of hardwoods and ivory select different tools than those used for cutting softwoods. Voids in
7280-517: The headstock (and the workpiece) are turret lathes . A lathe equipped with indexing plates, profile cutters, spiral or helical guides, etc., so as to enable ornamental turning is an ornamental lathe . Various combinations are possible: for example, a vertical lathe can have CNC capabilities as well (such as a CNC VTL ). Lathes can be combined with other machine tools, such as a drill press or vertical milling machine . These are usually referred to as combination lathes . Woodworking lathes are
7392-471: The headstock is the tailstock , sometimes referred to as the loose head, as it can be positioned at any convenient point on the bed by sliding it to the required area. The tail-stock contains a barrel, which does not rotate, but can slide in and out parallel to the axis of the bed and directly in line with the headstock spindle. The barrel is hollow and usually contains a taper to facilitate the gripping of various types of tooling. Its most common uses are to hold
7504-475: The headstock, or at right angles, but gently. When a workpiece is mounted with a certain axis of rotation, worked, then remounted with a new axis of rotation, this is referred to as "eccentric turning" or "multi-axis turning". The result is that various cross sections of the workpiece are rotationally symmetric, but the workpiece as a whole is not rotationally symmetric. This technique is used for camshafts, various types of chair legs. Lathes are usually 'sized' by
7616-427: The holding device or establishes depth cuts. Planning is done with a tool in which the bevel below the cutting edge supports wood fibers, just as in a typical wood planer. Beads are a convex shape relative to the cylinder, and coves are concave shape. Hollowing techniques are a combination of drilling and scooping out materials. The woodturner is at liberty to choose from a variety of tools for all of these techniques, and
7728-608: The increasingly sculptural explorations of woodturners. Unusually, woodturning never established a strong foothold in university departments of art and design. Instead, practitioners of the craft have become adept at learning from demonstrations, private classes, regional meetings, their own published journals, and internet technologies. Some artists began as woodturners, and moved into more sculptural work, experimenting with super object forms and other fine craft concepts. The Center for Art in Wood, founded in 1986 as The Wood Turning Center, houses
7840-600: The inventor of many subsequent improvements to the lathe worked as an apprentice in Verbruggen's workshop in Woolwich. 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
7952-410: The last line of the program. The format for a G-code is the letter G followed by two to three digits; for example G01. G-codes differ slightly between a mill and lathe application, for example: [Code Miscellaneous Functions (M-Code)] . M-codes are miscellaneous machine commands that do not command axis motion. The format for an M-code is the letter M followed by two to three digits; for example: Having
8064-478: The last of the apprentice-trained woodturners. A few years later, Canadian Stephen Hogbin spent a year in Australia, pushing the limits of the craft through changes in scale and design. Industrial arts teachers used their institutional affiliation to create seminars, publish books, and foster research. The tool industry identified a new market for lathes and turning tools. A small group of serious collectors invested in
8176-502: The lathe include tool handles, candlesticks , egg cups , knobs, lamps , rolling pins , cylindrical boxes, Christmas ornaments , bodkins, knitting needles, needle cases, thimbles , pens , chessmen , spinning tops ; legs, spindles, and pegs for furniture; balusters and newel posts for architecture ; baseball bats, hollow forms such as woodwind musical instruments, urns , sculptures; bowls, platters, and chair seats. Industrial production has replaced many of these products from
8288-414: The lathe is most often used with cylindrical work, it is useful to know the maximum diameter of work the lathe will hold. This is simply the value of the swing (or centre height above the bed) multiplied by two. For some reason, in the U.S. swing is assumed to be diameter but this is incorrect. To be clear on size, it is better, therefore, to describe the dimension as 'centre height above the bed'. As parts of
8400-517: The lathe reduce capacity, measurements such as 'swing over cross slide' or other named parts can be found. The smallest lathes are "jewelers lathes" or "watchmaker lathes", which, though often small enough to be held in one hand are normally fastened to a bench. There are rare and even smaller mini lathes made for precision cutting. The workpieces machined on a jeweler's lathe are often metal, but other softer materials can also be machined. Jeweler's lathes can be used with hand-held "graver" tools or with
8512-546: The left side of the headstock, where are no rails and therefore more clearance. In this configuration, the piece can be shaped inside and out. A specific curved tool-rest may be used to support tools while shaping the inside. Further detail can be found on the woodturning page. Most woodworking lathes are designed to be operated at a speed of between 200 and 1,400 revolutions per minute, with slightly over 1,000 rpm considered optimal for most such work, and with larger workpieces requiring lower speeds. One type of specialized lathe
8624-425: The machine is operated safely. However, during the 2000s and 2010s, the software for machining simulation has been maturing rapidly, and it is no longer uncommon for the entire machine tool envelope (including all axes, spindles, chucks, turrets, tool holders, tailstocks, fixtures, clamps, and stock) to be modeled accurately with 3D solid models , which allows the simulation software to predict fairly accurately whether
8736-402: The machine must be manually controlled (e.g. using devices such as hand wheels or levers) or mechanically controlled by pre-fabricated pattern guides (see pantograph mill ). However, these advantages come at significant cost in terms of both capital expenditure and job setup time. For some prototyping and small batch jobs, a good machine operator can have parts finished to a high standard whilst
8848-455: The machining code provided and it is up to an operator to detect if a crash is either occurring or about to occur, and for the operator to manually abort the active process. Machines equipped with load sensors can stop axis or spindle movement in response to an overload condition, but this does not prevent a crash from occurring. It may only limit the damage resulting from the crash. Some crashes may not ever overload any axis or spindle drives. If
8960-545: The making of prototypes and shapes for casting molds used in foundries during the 19th and 20th centuries. They worked very slowly to achieve precision, using enormous pattern maker lathes and slow-cutting scraping tools. Woodturning has always had a strong hobbyist presence. In the 1970s, an explosion of interest in hobby woodturning in the English-speaking world sparked a revival in the craft. Dr. Dale Nish traveled to England to recruit teachers, tools, and techniques from
9072-406: The maximum length of work the lathe will officially hold. It is possible to get slightly longer items in if the tailstock overhangs the end of the bed but this is an ill-advised practice. Purchasing an extension or larger bed would be a wise alternative. The other dimension of the workpiece is how far off-centre it can be. This is known as the 'swing' ("The distance from the head center of a lathe to
9184-470: The mechanism, by tightly applying pressure against the reference and setting that as the zero references for all following CNC-encoded motions. This is similar to the manual machine tool method of clamping a micrometer onto a reference beam and adjusting the Vernier dial to zero using that object as the reference. In numerical control systems, the position of the tool is defined by a set of instructions called
9296-421: The metal shaping tools. The tool-rest is usually removed during sanding, as it may be unsafe to have the operators hands between it and the spinning wood. Many woodworking lathes can also be used for making bowls and plates. The bowl or plate needs only to be held at the bottom by one side of the lathe. It is usually attached to a metal face plate attached to the spindle. With many lathes, this operation happens on
9408-464: The motor speed into various spindle speeds . Various types of speed-changing mechanism achieve this, from a cone pulley or step pulley, to a cone pulley with back gear (which is essentially a low range, similar in net effect to the two-speed rear of a truck), to an entire gear train similar to that of a manual-shift automotive transmission . Some motors have electronic rheostat-type speed controls, which obviates cone pulleys or gears. The counterpoint to
9520-404: The oldest variety, apart from pottery wheels. All other varieties are descended from these simple lathes. An adjustable horizontal metal rail, the tool-rest, between the material and the operator accommodates the positioning of shaping tools, which are usually hand-held. After shaping, it is common practice to press and slide sandpaper against the still-spinning object to smooth the surface made with
9632-481: The order of 100mm /min, as compared to 8x10 mm /min for conventional machining, but it can generate features that conventional machining cannot. Wire EDM operates by using a thin conductive wire, typically brass, as the electrode, and discharging as it runs past the part being machined. This is useful for complex profiles with inside 90 degree corners that would be challenging to machine with conventional methods. Many other tools have CNC variants, including: In CNC,
9744-412: The part being machined so that it must be scrapped. Many CNC tools have no inherent sense of the absolute position of the table or tools when turned on. They must be manually "homed" or "zeroed" to have any reference to work from, and these limits are just for figuring out the location of the part to work with it and are no hard motion limit on the mechanism. It is often possible to drive the machine outside
9856-485: The physical bounds of its drive mechanism, resulting in a collision with itself or damage to the drive mechanism. Many machines implement control parameters limiting axis motion past a certain limit in addition to physical limit switches . However, these parameters can often be changed by the operator. Many CNC tools also do not know anything about their working environment. Machines may have load sensing systems on spindle and axis drives, but some do not. They blindly follow
9968-404: The power source. Beginning in the 1950s, servomechanisms were applied to the control of lathes and other machine tools via numerical control, which often was coupled with computers to yield computerized numerical control (CNC) . Today manually controlled and CNC lathes coexist in the manufacturing industries. A lathe may or may not have legs, which sit on the floor and elevate the lathe bed to
10080-461: The precision of some operations involving axis movement reversals during cutting, such as the milling of a circle, where axis motion is sinusoidal. However, this can be compensated for if the amount of backlash is precisely known by linear encoders or manual measurement. The high backlash mechanism itself is not necessarily relied on to be repeatedly precise for the cutting process, but some other reference object or precision surface may be used to zero
10192-478: The primary role. Lathes of this size that are designed for mass manufacture, but not offering the versatile screw-cutting capabilities of the engine or bench lathe, are referred to as "second operation" lathes. Lathes with a very large spindle bore and a chuck on both ends of the spindle are called "oil field lathes". Fully automatic mechanical lathes, employing cams and gear trains for controlled movement, are called screw machines . Lathes that are controlled by
10304-399: The quality of the cuts improves with practice wielding the tool selected. Turners rely upon three points of contact making any type of cut: the tool presses down on the tool rest, and against the woodturner's body before contacting the surface of the wood, most often with a bevel edge riding the surface of the wood. The objective is to position the tool correctly so that the wood comes around to
10416-433: The reciprocating lathe's rotation. Even with continuous revolution, however, the turner controls the contact of tools and wood entirely by hand. The cutters are not fixed, nor advanced automatically, as with the metal-working lathe. The nature of wood defines woodturning techniques. The orientation of the wood grain, relative to the axis of the lathe, affects the tools and techniques used by the woodturner. In spindle turning,
10528-419: The safety before starting the lathe is ' SAFER' : Safe usage of a lathe also depends on the operator's choice of proper techniques for the lathe, tools, and wood. For example, using a high spindle speed with an unbalanced wooden blank may cause the lathe to vibrate dangerously. Spinning a large turning blank too quickly may cause it to explode. Inappropriate use of tools such as gouges and skew chisels can cause
10640-474: The series of steps needed to produce any part is highly automated and produces a part that meets every specification in the original CAD drawing, where each specification includes a tolerance. Motion is controlling multiple axes, normally at least two (X and Y), and a tool spindle that moves in the Z (depth). The position of the tool is driven by direct-drive stepper motors or servo motors to provide highly accurate movements, or in older designs, motors through
10752-528: The source of wood for turning furniture parts. In the 19th and early 20th century, woodturners in England worked in Turning Shops, usually within the master-apprentice system. In Germany and Russia, woodturning was concentrated in villages that had a specialty, such as turning toys. Bow lathes and pole lathes continued in use for decentralized, one-man production of architectural elements and bowls in many parts of
10864-427: The stock material to give a starting point or "home position" before starting the actual machining. G-codes are used to command specific movements of the machine, such as machine moves or drilling functions. The majority of G-code programs start with a percent (%) symbol on the first line, then followed by an "O" with a numerical name for the program (i.e. "O0001") on the second line, then another percent (%) symbol on
10976-499: The tactile and visual qualities of wood. Wood lathes work with either reciprocating or continuous revolution. The reciprocating lathe is powered by a bow or a spring, rotating the wood first in one direction, and then in the other. The turner cuts on just one side of the rotation, as with the pole lathe . The reciprocating lathe may be human-powered with a bow, as well as with spring mechanisms. The reciprocating lathe, while primitive technology requiring considerable dexterity to operate,
11088-695: The three types, high-speed steel tools maintain their edge longer, requiring less frequent sharpening than carbon steel, but not as long as tungsten carbide. Tungsten carbide tools typically consist of scraping tools with the disposable carbide insert attached to the tool. The harder the type of high-speed steel used, the longer the edge will maintain sharpness. Tungsten carbide inserts are generally thought of as disposable, but they can be sharpened with diamond abrasives . Modern cutting and scraping tools can also be coated with titanium nitride to improve wear characteristics. Woodturning tools must be sharpened more frequently than other edged woodworking tools to maintain
11200-426: The tool is cutting across the grain and even upwards across it. This varying grain angle limits some of the tools that may be used and require additional skill from the turner. Moisture content affects both the ease of cutting wood and the final shape of the work when it dries. Wetter wood cuts easily with a continuous ribbon of relatively dust-free shavings. However, the wet wood moves as it dries. shrinking less along
11312-672: The tool. By the 1770s, precision lathes became practical and well-known. A slide-rest is clearly shown in a 1772 edition of the Encyclopédie and during that same year a horse-powered cannon boring lathe was installed in the Royal Arsenal in Woolwich , England by Jan Verbruggen . Cannon bored by Verbruggen's lathe were stronger and more accurate than their predecessors and saw service in American Revolutionary War . Henry Maudslay ,
11424-456: The traditional milling and turning , other machines and equipment are also installed with the corresponding CNC, which makes the manufacturing industry in its support, greatly improving the quality and efficiency. Of course, the latest trend in CNC is to combine traditional subtractive manufacturing with additive manufacturing (3D printing) to create a new manufacturing method - hybrid additive subtractive manufacturing (HASM). Another trend
11536-655: The traditional turning shop. However, the wood lathe is still used for decentralized production of limited or custom turnings. A skilled turner can produce a wide variety of objects with five or six simple tools. The tools can be reshaped easily for the task at hand. In many parts of the world, the lathe has been a portable tool that goes to the source of the wood or adapts to temporary workspaces. 21st-century turners restore furniture, continue folk-art traditions, produce custom architectural work, and create fine crafts for galleries. Woodturning appeals to people who like to work with their hands, find pleasure in problem-solving, or enjoy
11648-428: The turning extend farther from the axis of rotation and are sometimes more difficult to see than the bulk of the wooden blank. Numerical control In machining , numerical control , also called computer numerical control ( CNC ), is the automated control of tools by means of a computer . It is used to operate tools such as drills , lathes , mills , grinders , routers and 3D printers . CNC transforms
11760-555: The use of a traveling or fixed steady . If a steady is not available, the end face being worked on may be supported by a dead (stationary) half center. A half center has a flat surface machined across a broad section of half of its diameter at the pointed end. A small section of the tip of the dead center is retained to ensure concentricity. Lubrication must be applied at this point of contact and tail stock pressure reduced. A lathe carrier or lathe dog may also be employed when turning between two centers. In woodturning, one variation of
11872-476: The vast majority of backlash, it still must be taken into account. CNC tools with a large amount of mechanical backlash can still be highly precise if the drive or cutting mechanism is only driven to apply cutting force from one direction, and all driving systems are pressed tightly together in that one cutting direction. However, a CNC device with high backlash and a dull cutting tool can lead to cutter chatter and possible workpiece gouging. The backlash also affects
11984-401: The wood require higher lathe speeds, fillers, or extra safety precautions. Although other woodworkers value tight, straight grain, woodturners often search out the unusual wood from roots, defects, or diseased portions of trees. The craft of woodturning is preserved and advanced by a community of practitioners. Until the 1970s, an apprentice system in the U.K., and Industrial Arts education in
12096-440: The workpiece, via tools, at a right angle to the axis of rotation, without fear that the workpiece may break loose. When a workpiece is fixed only to the spindle at the headstock end, the work is said to be "face work". When a workpiece is supported in this manner, less force may be applied to the workpiece, via tools, at a right angle to the axis of rotation, lest the workpiece rip free. Thus, most work must be done axially, towards
12208-431: The workpiece. Other accessories, including items such as taper turning attachments, knurling tools, vertical slides, fixed and traveling steadies, etc., increase the versatility of a lathe and the range of work it may perform. When a workpiece is fixed between the headstock and the tail-stock, it is said to be "between centers". When a workpiece is supported at both ends, it is more stable, and more force may be applied to
12320-403: The workpiece. Unless a workpiece has a taper machined onto it which perfectly matches the internal taper in the spindle, or has threads which perfectly match the external threads on the spindle (two conditions which rarely exist), an accessory must be used to mount a workpiece to the spindle. A workpiece may be bolted or screwed to a faceplate , a large, flat disk that mounts to the spindle. In
12432-447: The world. In the US, woodturning was part of the curriculum of industrial arts taught in public schools—often a prerequisite for classes in building furniture. The 'problems' from textbooks included both tool management skills, and assignments to turn objects such as gavels, darning eggs, boxes, trays, candlesticks, lamps, and legs for furniture. Woodturning skills were used by patternmakers in
12544-518: Was assigned responsibility for regulating weights and measures by the Mayor. By 1591, they built their own Hall. The Company governed the apprentice system and established pricing for goods. In 1604, they were incorporated as the Worshipful Company of Turners of London. Outside of London, the craft was decentralized and unregulated. Itinerant turners known as Bodgers set up temporary pole lathes near
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