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Woodturning is a form of woodworking, that is used to create wooden objects (e.g. a bowl or a table leg) on a lathe using cutting tools. Woodturning differs from most other forms of woodworking, in that the wood is moving while a (relatively) 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 or turning between centers and faceplate turning. In spindle turning, the grain of the wood runs lengthwise, and the piece is typically spun on centers between the headstock of the lathe and the tailstock, with material removed from the side of the wood. In face plate turning, the grain of the wood runs perpendicular to the axis of rotation, and the piece is often attached to the lathe via a plate or a chuck. Most bowls, platters and vessels are face plate turned, while pens, table legs, and other slender pieces are typically spindle turned. Regardless of the method of attachment, the orientation of the grain determines the method in use, the type of tools to use, and the direction of cut.
History
The origin of woodworking dates to around 1300BC 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. 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 accurate 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.
Common woodturned items
- Furniture parts - spindles, table legs, stretchers, or other furniture parts
- Bowls - vessels with a large opening on top
- Platters and serving trays
- Pens, mechanical pencils, keyrings and other small items
- Hollow forms - similar to bowls, except usually taller and with a small opening, when compared to the hollow interior
- Pepper mills and candlesticks
- Chess pieces (some cutting is required after turning)
- Sculptural forms
- Pool cues and baseball bats
Woodturning 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. However, the powdered steels do not take an edge that is as sharp as HSS. Unlike other edged woodworking tools, woodturning tools require more frequent sharpening and the sharpening process requires either skill of the craftsman, or one of the many available sharpening jigs. To maintain a clean cut, the sharpness of the tools edge must be maintained. Often the tools are sharpened by using a sharpening jig, these jigs facilitate maintaining a specific bevel on the tool.
Types
- roughing gouge - a wide fluted gouge used to initially round a wooden spindle, and to roughly shape it. Generally not intended for cutting end grain, so not recommended when making bowl.
- spindle gouge or detail gouge - a shallow fluted gouge used to create details on spindles, including beads and coves
- bowl gouge - a deep fluted gouge used to turn the outside and inside of bowls and vessels. Often has a thicker shaft than roughing gouge so that it can cut through the end grain in bowls without breaking.
- skew chisel - a wide, steeply pointed chisel used to smooth flat spindles, cut beads, and add details
- parting tool - a pointed tool used to separate (part off) work from the lathe, and to create a straight edge separating large and small diameter sections - wide parting tools are used to create evenly sized spindle sections
- hollowing tool - many different types of tools used to cut out the deep sections of steep bowls and hollow vessels
- scraper - a tool that scrapes the wood fibers instead of cutting - these are used to smooth off wooden items cut with other tools, and to shape items that are not possible or difficult to shape with gouges
- bowl saver - a tool used to core out the inside part of a bowl, allowing the waste piece to be used to create a smaller bowl
- auger - a drill bit used to drill a hole partway or all the way through a wooden item. For cutting the hole for a lamp cord, or as the first step when hollowing out a bowl or vessel
- chatter tool - a flexible scraper used to add decorative chatter marks to turned items
- there are also several tool types for special purposes, as well as tools that are a combination design of the above tools, i.e. skew/chisel combinations, thread cutting tools, ring cutting tools, medium fluted gouges, etc
Other Techniques
- eccentric turning - turning a single piece multiple times, upon different axises 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
- therming - mounting a carrier between centers, and then mounting the small workpiece(s) to the carrier, so that the axis of the headstock/tail-stock does not pass through any of the workpieces, and each workpiece gets cut only on one face. As noted in Wood-turning Methods by Mike Darlow, the etymology of the term "therming" comes via a corruption of the name of the Greek god Hermes, who was often represented as a statue set atop a plinth with a construction characteristic of thermed work.
- segmented turning - a method of woodturning where the wood blank is constructed from many individual pieces of wood (segments) which are laminated together before being turned. Many interesting patterns can be generated through the process of lamination and shaping on the lathe.
Safety
When woodturning, it is important to wear certain personal protective equipment (PPE). Loose clothing should not be worn, all jewelry should be removed, and long hair should be tied back. Wood shavings generated during turning will also 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, some of which feature built-in respirators. Although all of these are adequate, for the highest level of protection, a visor that protects the entire head from dust and debris should be worn.
- Respiratory equipment is 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 built in respirator. Most stand alone respiratory equipment will interfere with dust shields and visors, so devices that incorporate both are available.
- Ear protection Compared to other power tools, a lathe is a relatively quiet machine. Ear protection should be used if noise is excessive, this may be due to motor (fan) noise from a shop dust collector, or the combination of wood and tool being used.
- Foot protection. Protective footwear is a must for any type of shop activity.
See also
External links
"Woodturning"