Woodturning

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A woodturning workshop at an alternative-lifestyles festival, New Zealand 1978.

Woodturning is a form of woodworking that is used to create wooden objects on a lathe (see: also antique wooden polelathe). Woodturning differs from most other forms of woodworking in that the wood is moving while a stationary tool is used to cut and shape it. Many intricate shapes and designs can be made by turning wood.

There are two distinct methods of turning wood: spindle turning and faceplate turning. In spindle turning, the wood is fixed between 2 points. The spur center digs in to the wood and is powered by a motor. The other, a hard center or a live center may be a point or set of points in the tail-stock. In face plate turning, the wood is secured with screws to a faceplate or in a chuck or jig. the tail stock and a center may also be used for added support on large pieces with a faceplate. Most bowls, platters and many vessels are face plate turned, while, Pens, furniture legs, spindles, and some vessels are spindle turned. The method used may differ depending on the shape of the blank and the technique of the turner, and both methods may be used on the same piece.

When wood is cut in such a way that the fibre being cut is not supported by the fibre below it, it tends to separate and tear. This "tear out" exhibits a rough, highly damaged looking surface texture and greatly reduces the value of any product exhibiting it. The direction of cut is different in spindle turning and faceplate turning because cutting in the wrong direction can cause tear out. Spindle turning cuts are made from high points toward the axis on the outside of the piece, and from the axis toward the outside when hollowing. When faceplate turning, the opposite applies.

Contents

History

A turned wood bowl with natural edges

The origin of woodturning dates to around 1300 BC when the Egyptians first developed a two-person lathe. One person would turn the wood with a rope while the other used a sharp tool to cut shapes in the wood. The Romans improved the Egyptian design with the addition of a turning bow. Early bow lathes were also developed and used in Germany, France and Britain. In the Middle Ages a pedal replaced hand-operated turning, freeing both the craftsman's hands to hold the woodturning tools. The pedal was usually connected to a pole, often a straight-grained sapling. The system today is called the "spring pole" lathe (see Polelathe). Spring pole lathes were in common use into the early 20th Century. A two-person lathe, called a "great lathe", allowed a piece to turn continuously (like today's power lathes). A master would cut the wood while an apprentice turned the crank.

The term "bodger" stems from pole lathe turners who used to make the chair legs and spindles. A bodger would typically purchase all the trees on a plot of land, set up camp on the plot, and then fell the trees and turn the wood. The spindles and legs that were produced were sold in bulk, for pence per dozen. The bodger's job was considered unfinished because he only made component parts. The term now describes a person who leaves a job unfinished, or does it badly.

During the industrial revolution the lathe was motorized, allowing turned items to be created in less time. The motor also produced a greater rotational speed for the wood, making it easier to quickly produce high quality work. Today most commercial woodturning is done by computer-operated machinery allowing for mass-production that can be created with precision and without the cost of employing craftsmen. Despite this, there is still a demand for hand-turned products. Woodturning is also a hobby enjoyed by many people.

Modern professional woodturners are typically either "production" turners producing large quantities of functional pieces, or artistic turners producing smaller numbers of pieces, often enhanced after turning by carving, piercing, coloring, applying pyrography, gilding, or a number of other techniques to produce objects for the art market.

Common woodturned items

Tools

Turning tools are generally made from three different types of steel, Carbon steel, High speed steel (HSS), and more recently Powdered Metal. Comparing the three types, high speed steel tools maintain their edge longer, requiring less frequent sharpening than carbon steel, but not as long as powdered metal tools. The harder the type of high speed steel used, the longer the edge will maintain sharpness. Powdered steel is even harder than HSS, but takes more effort to obtain an edge as sharp as HSS, just as HSS is harder to get as sharp as Carbon Steel. Unlike other edged woodworking tools, woodturning tools require more frequent sharpening, because the wood passes at a great speed. To maintain a clean cut, the sharpness of the tools edge must be maintained. The 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. High speed steel is not prone to blueing (overheating) whereas carbon steel blues easily, requiring frequent quenching to avoid losing temper (making the edge too soft.)

Types

Other techniques

Safety

When woodturning, it is important to wear certain personal protective equipment (PPE). Loose clothing should not be worn, all jewellery should be removed, and long hair should be tied back. Wood shavings generated during turning will also need to be periodically removed.

A good way to check the safety before starting the lathe is 'SAFER':

Safe usage of a lathe also depends on the operator knowing proper techniques and being aware of the limitations of both the machine and the workpiece. For example, using a high spindle speed with an unbalanced workpiece may cause the lathe to vibrate dangerously. Spinning a large workpiece too fast may cause it to explode. Inappropriate use of tools such as gouges and skew chisels can cause a catch, where the tool bites suddenly and aggressively into the wood in an uncontrolled manner. This exerts very large forces on the workpiece, the tool, the lathe and the operator, often causing the workpiece to break apart or tear free from the lathe or pulling the tool out of the operator's hands and throwing it through the air.

See also

External links

en:woodturning