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Woodturning

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Woodturning is the craft of using the 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 simple mechanism which can generate a variety of forms. The operator is known as 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 misterie' 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 machinists lathe, or metal-working lathe. Items made on 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 woo

Overview

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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, 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 the reciprocating lathe's rotation. Even with continuous revolution, however, the turner controls the contact of tool and wood entirely by han

History

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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 own variations of the bow lathe. Early lathe workers would sometimes use their bare feet to hold cutting tools in place while using their hand 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 bowls excavated from shipwrecks, such as the Mary Rose and the Oseberg burial ship, or dug out of deep wells, where they were preserved in a nonaerobic environment. Much of this ware was turned

Techniques

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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 the holding device, or establishes depth cuts. Planing 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 a 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 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 the cutti

Holding devices

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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 a cup, collet, or a 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.

Tools

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Turning tools are generally made from carbon steel, high speed steel (HSS), and more recently Tungsten carbide. Comparing 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 nitrite to improve wear characteristics. Woodturning tools must be sharpened more frequently than other edged woodworking tools to maintain 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 pro

Other techniques

Eccentric turning – turning a single piece multiple times, upon different axes each time. Oval or elliptical turning – turning a piece using an accessory mounted to the headstock that changes the center of rotation of the piece in time with the rotation, so that a cutting tool held in a fixed position on the tool-rest cuts an oval rather than a round path on the workpiece Sculptureturnery – turning on a lathe that will generate turned work that is not necessarily circular, can be any of the following cross –sections; elliptical, triangular, square, pentangle, hexagonal, heptangular. Multi-dimensional wood turning – requires that the work piece as it rotates will be able to move cyclically along the lathe bed and/or simultaneously move cyclically across the bed. Three dimensional woodturning – is where the shape produced by the lathe is not symmetrical about the axis of rotation. Therming – mounting a carrier between centers, and then mounting the small workpiece(s) to the carrier,

Safety

When woodturning, it is important to wear certain personal protective equipment (PPE). When working with spinning objects, loose clothing should not be worn; all jewellery 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. Eye protection is a necessity when woodturning. There are several PPE available for eye protection such as safety goggles, glasses, and visors. Although all of these are adequate, a visor that protects the entire head from dust and debris provides the highest level of protection. Respiratory equipment and dust collection systems are also important when woodturning or doing any type of woodworking that creates dust. This can range from a simple disposable dust mask to a full face helmet with a built in respirator. Most standalone respiratory equipment will interfere with du

Notable woodturners

Richard Raffan