Multimedia Woodturning Glossary

Welcome to the Woodturning Videos Plus Multimedia Woodturning Glossary. This glossary will be updated on a regular basis, so be sure to bookmark this page for future reference. Listings in this woodturning glossary will feature commonly used regional and country specific terms, as well as slang terms for various tools, techniques, finishes, machinery, abrasives and miscellaneous terms used in woodturning.

Where possible, this glossary will feature not only written definitions for each word, but also pictures, video clips, drawings, audio clips and other supplemental information to enhance the users understanding of each term. Photos, videos and drawings will be added in stages to existing text entries in the glossary, once they can be edited and uploaded.

When complete, this glossary will contain over 4,500 words and phrases and will be the most comprehensive woodturning glossary reference available on the Internet for woodturners.

The alphabetical links listed below will advance you to the specific letter indicated. As the glossary continues to grow, alphabet groups will be broken out into individual pages (for example A, B and C on one page, D, E and F on another etc.) to keep page load times fast. If you have any suggestions for entries in this glossary, please email me. Thanks!

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Woodturning Glossary - Quick Jump Alphabet Selector

Woodturning Glossary A through C

A

Abrasive - Abrasives can be simply defined as materials that are used to shape, smooth, sculpt, or finish an object by rubbing, resulting in wear to the surface. When the abrasive is applied to a backing such as paper, cloth, or film, it is commonly referred to as sandpaper, finishing paper, or sanding cloth.

Various sheet, roll and disk abrasives

Abrasive Grade – Specifies the grit size of an abrasive product. There is an inverse relationship to the size of the abrasive grains and the grade number, thus the higher the grade number, the smaller the grain size.

Abrasive Grading - Abrasives contain various particle sizes, including the stated grain size and others that fail to meet the specification. Grading is the process used to make the abrasive particles more uniform in size. Most abrasive grains larger than 220-grit are mechanically sifted through screens. Grits finer than 240-grit typically utilize fractional sedimentation in water to size the grains. Other procedures employed include air blown sifting and elutriation in water.

Abrasive Classification Systems - Two primary standards exist for classifying the grit size of abrasives. In the U.S., the CAMI (Coated Abrasives Manufacturing Institute) standard is used; Europe uses the FEPA (Federation of European Producers of Abrasives) standard. Japan uses the JIS (Japanese Industrial Standard), which is equivalent to the FEPA standard. FEPA graded abrasives can be easily distinguished by the letter "P" in front of the grit number, such as P240. There are sizing differences between the CAMI and FEPA standards, so the two standards are not universal.

Accelerator - A substance used to speed the curing of adhesives (Super Glue for example), impregnants, sealants, or encapsulation compounds. Also known as a Catalyst, or Kicker.

Various CA Accelerators

Acetone - Acetone (Also known as: 2-Propanone or Dimethyl Ketone) is a powerful, fast acting Ketone solvent for epoxies, polyester, vinyl, lacquer, contact cement, plastics and adhesives. Acetone is a clear, colourless liquid with a sharp penetrating, non-residual odour at ambient temperatures. It is miscible in all proportions with water. Acetone is an excellent solvent for gums, waxes, resins, fats, oils, dyes and cellulosics. Most of the manufactured acetone is obtained as a co-product of phenol from the Cumene process. The balance is manufactured by dehydrogenating Isopropyl Alcohol.

Acetone

Adherend - The substrate after bonding is known as the adherend. Adhesion - The state in which two surfaces are held together by chemical or mechanical interfacial forces, or by a combination of the two. Airbrush - A small, pencil shaped air tool that sprays atomized inks, dyes and thin paints. Airbrushes work by passing compressed air through a venturi, this creates suction that allows the fluid to be pulled up from an attached reservoir. Some airbrushes use gravity fed reservoirs for supplying paints. In woodturning, airbrushes are frequently used to apply dyes and other colouring products to turned forms and are one of the best ways to blend multiple colours on a project.

Airbrushes are popular tools for colouring woodturnings

Air-Drying – A method of drying green timber such as turning squares, blanks, or roughouts whereby the wood is allowed to dry, or season exposed to natural atmospheric conditions in the open air. The endgrain and high figured areas are typically coated with a cold wax emulsion (endgrain sealer) to reduce any checking. In areas with very low humidity, the entire blank, or roughout is frequently coated with a cold wax emulsion. Air drying green wood preserves subtle colours and delicate highlights in the timber that are usually destroyed by kiln drying.

Applying wax emulsion to a bowl blank to prepare it for open air drying

Alternative Material - Any turning material not made of wood. This includes man-made plastics, composites, antler, horn, bone, Ivory, crushed stone and soft metals like brass, aluminum, copper and pewter that are popular for turning, or for use as inlay materials. Turning alternative materials may require special tools, abrasives, or finishing protocols.

Deer Antler is a popular alternative material to use for writing pens

Alumina Zirconia – A synthetic abrasive that features a self-sharpening crystalline structure with blocky shaped grains. Alumina Zirconia is manufactured from Aluminum Oxide and Zirconium Oxide and is quenched when molten, producing a crystalline structure that fractures well in use, revealing new cutting edges.

Alumina Zirconia abrasive wheels

Anaerobic Adhesives – Contain an acrylic, or methacrylic monomer and cure due to the absence of oxygen. Excellent for use on grub screws in boring bars to prevent loosening from shock or vibration, or to seal pipe fittings and machine fasteners. Special versions available for plastic fasteners. Standard versions not recommended for permeable surfaces like plastics and rubber. Special primers are required with passive metals, large bond gaps, or inert surfaces.

Angle Finder - (1) A jig with pre-cut angle notches that is used to determine the bevel angle on gouges and other woodturning tools. (2) Any one of several jigs used to determine the angle of cutting tools and other items. These jigs include simple adjustable arm models, through electronic models that accurately determine angles of saw blades, cutting tables and other equipment used in woodturning studios.

Various angle finder tools

Angle Jigs - Any jig that is used to quickly find the bevel angle on woodturning tools, for example the Tormek Angle Jig.

The Tormek and Woodcut angle jigs

ANSI - American National Standards Institute - Organization maintaining standards used by many different industries.

Anti-Kickback Chain - A specially designed type of chainsaw chain that reduces the chances of kickback when the nose of the bar is pinched in the cut, or when the nose tip encounters solid wood.

Antistatic Coating - A special coating applied to some abrasives to reduce static electricity buildup on the surface of the abrasive. Antistatic coatings help to reduce loading and heat build-up on the surface of the abrasive and increase the efficiency of dust removal by collection equipment.

Anti-Vibration Handle - Chainsaw handles that are designed with isolating/shock absorbing mountings that help to reduce the vibration felt through the handle when cutting. Anti-vibration handles help to reduce the chances of hand fatigue and allow the operator to work for extended periods of time with greater comfort.

Aqueous - Products that are based on, or related to compositions that contain water.

Arbor – (1) A shaft used to mount sanding mandrels, small grinding wheels, cones, sanding stars, flap wheels and similar items for use in power tools. (2) A Morse taper fitting that is used for mounting various fixings like drive spurs, buffing wheels, revolving ball bearing centres, Jacob's chucks and other tools in the lathe headstock, or tailstock.

This 6" buffing wheel is mounted on a #2 Morse Taper arbor extension

Arbortech Mini-Grinder – High speed rotary carving tool developed in Australia that fits standard 4" and 4.5" right angle grinders. The cutting blades feature tungsten steel teeth, or a stamped steel cutting wheel depending on the options purchased. Highly regarded as one of the best carving and shaping tools for embellishing/carving woodturnings.

Arbortech Mini-Grinders feature 2" cutting wheels

Arbortech Power Chisel – High speed reciprocating carving tool developed in Australia that fits standard 4" and 4.5" right angle grinders. The carving blades are made from high carbon steel and are easily sharpened. Highly regarded as the most powerful reciprocating carving tool available for carving woodturnings.

Arbortech's Power Chisel

Atomize - The reduction of a liquid to an ultra-fine spray using high pressure air, or with only high pressure as if found in airless sprayers.

B

Band Sander - A small handheld belt sander that is used to sand in very restricted areas. Proxxon's mini-belt sander uses a 13/32" wide abrasive belt that is 13" long and features a variable speed motor (985 - 2,300 FPM). Band sanders are popular tools to use when doing deeply carved, sculpted or pierced surfaces on woodturnings. Band sanders are also known as Mini-Belt Sanders.

Proxxon mini-band sander

Barrel – A part of the tailstock assembly. Also known as the Tailstock Ram. The barrel is a cylindrical metal rod that features a Morse taper fitting on one end and a rotating hand wheel on the other. When the hand wheel is turned on the tailstock, the barrel is pushed out pressing the tailstock accessory (ball-bearing center) against the work piece.

Bead - A convex shaped, round design element on a project that stands proud of the surface. Beads can be turned in many different ways including full round (a free floating bead that is not attached to the project surface, also called a captive ring), round, half round ( only ½ of the bead surface is rounded) and quarter round ( only ¼ of the bead surface is rounded).

Beeswax - Beeswax is a glandular secretion from young worker honeybees and is used to build their honeycomb structures. The wax is harvested by removing the honey through centrifuging and melting the remaining comb. The melted wax is then filtered and cast into moulds. Contaminants such as pollen, gums and resins add various colours to the wax, which can range from yellow to brown. Beeswax is a medium hard wax with a penetration of 20 dmm at 25 degrees Centigrade and 76 dmm at 43.3 degrees Centigrade (ASTM D1321). It is slightly tacky and has a melting point of approximately 64 degrees Centigrade. Used by itself, it produces a pleasant satin finish. It is frequently used as a base ingredient in many traditional wax finishes.

Solid beeswax bars

Bedway – The long part of the lathe that connects the headstock and the tailstock sections together. The lathe bedway can be flat steel, or cast iron (most common types), or rounded steel bars. In recent years, some manufacturers have introduced lathes with bedways made from stainless steel to eliminate rust concerns when working with green wood.

Bedan - A woodturning chisel with a wedge shaped cross section. It is used in spindle turning to create design elements. Some bedan chisels do not have wedge shapes, depending on the place of manufacture. Very popular in European countries and especially in France.

Between Centers – (1) Turning between centers describes work that is mounted between the headstock and the tailstock. Turning between centers typically involves a spindle, or bowl blank mounted between a drive spur in the headstock and revolving ball bearing center in the tailstock. (2) Industry specification that relates to the maximum distance the lathe offers between the headstock and the tailstock.

Letter opener handle being turned between centers

Bevel – The sharpened/ground surface on a woodturning tool. This is typically referred to as the "bevel edge" and includes the overall design and shape of the bevel, as well as the angle of the bevel in relation to the shaft of the tool.

1/4" micro spindle gouge with a 35 degree front bevel

Bevel Rubbing Tools - Turning tools that are used with their bevel in contact with the surface of the wood during cutting. Primary examples of these would include bowl and spindle gouges, as well as the skew chisel.

Birdseye - Numerous small rounded or oval shaped areas on the surface of sawn wood that are similar in appearance to a bird's eyes. Commonly found in some Hard Maples, and in occasionally with other species.

Blank – The rough piece of wood after it has been cut and processed for turning on the lathe. Faceplate blanks for bowls and platters may be rounds, or square. Spindle blanks are typically long square sections.

Bleaching Agent - Any product that makes the colour of an object permanently lighter in colour. Two-part wood bleaches are a typical example.

Blended Oils - Blended oil/varnishes are blends of various oils and varnishes. The ratio of oil to varnish, as well as the specific oil or varnish used, determines the physical characteristics of the final finish. Oils extend the curing time and soften the luster and hardness of the final finish. Varnishes increase the body of the finish and provide increased hardness, luster, water resistance and scratch protection.

Board Foot - A unit of measure for lumber products. One board foot is equal to one square board measuring 1" thick that is 12" by 12" in size (144 cubic inches). To calculate the board foot measurement for random sized boards, multiply the thickness x the width x the length (all in inches) and divide by 144. Board Foot measurements are commonly expressed as "BF", for example: 45 BF of Hard Maple.

Bodied Oils - Nonconjugated and conjugated drying oils like linseed and tung that have been polymerized by heating in an inert atmosphere. These polymerized oils are then referred to as “Bodied Oils.” To achieve the higher viscosities of bodied oils, nonconjugated oils are heated up to 320° Centigrade and conjugated oils are heated up to 240° Centigrade. This increase in viscosity, or “body,” is caused from thermal decomposition of naturally occurring hydroperoxides. This decomposition yields free radicals that contribute to a limited amount of cross-linking.

Bodger - An early pole lathe turner. Bodgers used lathes that were powered by human energy mechanisms such as foot treadles, the spring tension of a tree sapling, a twisted cord, or a treadmill.

Boiled Linseed Oil - Boiled linseed oil is linseed oil that has been altered through the addition of chemical drying accelerators, i.e. solvents and siccatives/driers. This treatment allows the manufacturer to reduce the V.O.C (volatile organic compounds) content, while maintaining the viscosity. Boiled linseed oil is frequently mixed with 10-15% Stand Oil.

Boiling Wood Protocol - A method to speed the drying of green wood by boiling it in water for a specific period of time. Developed by professional woodturner Steve Russell of Eurowood Werks Studio, this protocol also reduces drying degrade significantly in boiled pieces versus typical open air drying. Today, this protocol is used around the world by many woodturners and some commercial timber exporters to reduce checking and speed the drying of green wood roughouts, blanks and turning squares.

Loading several bowls into a boiling pot

Bonding - The process of assembling materials with adhesives or glues at ambient temperatures, or elevated temperatures.

Bond Line - The area or space between two substrates that contains the adhesive.

Bone Grubber - A very old slang term for an English woodturner who specialized in turning hardwood and ivory.

Boundary Layer – The area between the adhesive and the substrate.

Bow - Warping in a board where the timber deviates from flatness lengthwise, but not across the faces.

Bowl Buff - A round cloth, or mushroom shaped buffing wheel made for buffing cured finishes on the inside of bowls, goblets and other projects with interior curves. Bowl buffs are also known as Mushroom Buffs, or Ball Buffs. Bowl buffs are typically used with a buffing compound like Tripoli, or White Diamond and may be used on the lathe with a Morse taper adapter, or on a dedicated buffing machine.

Using a bowl buff on the inside of a Curly Koa bowl

Bowl Saver - See Centre Saver.

Boxes - Turned decorative, or functional forms that are cylindrical in shape. Boxes are usually turned and hollowed from endgrain blanks and feature a suction fit lid, or a loose fitting lid depending on the turners preference.

Break-In - A procedure to break in new bandsaw blades that involves using lighter feed pressure than normal for the first one to two dozen cutting operations. New blades that are broken in this way typically experience greater overall band life.

Brinell Hardness Test - Similar to Rockwell hardness testing (see Rockwell Hardness Test), a Brinell test measures the area of impression (not the depth) created when a hard 10mm diameter (0.3937 in) ball is pressed into the metal under a 3,000 kilogram (6,600 lb) load.

Brittleness - The tendency of a material to break or fracture with very little to no deformation, twisting or bending. With metals, brittleness typically increases as hardness increases.

Brown Aluminum Oxide - (2090 Knoop Scale) Brown Aluminum Oxide (BAO) is a medium density fused Aluminum Oxide that contains a medium amount of Titania. BAO may also contain varying amounts of Silicon, Titanium Oxide, or a higher amount of Titania.

Bucking Spikes - Sharp saw tooth shaped spikes on the front body of a chainsaw that are located where the bar is attached. Bucking spikes are pressed into the side of the log or timber section during cutting and help to keep the cut straight. They also help to reduce the chances that the bar will elevate unexpectedly during the cut. Smaller saws may only have one bucking spike on the saw, larger saws usually have one set on each side of the chain.

Bullnose - A term that describes a full rounded end (semi-hemispherical) on a scraper. Some turners refer to bullnose edges as full-round. Also known as a Domed Scraper.

Burr/Burl - A lumpy, warty looking growth on a tree that may have tiny twigs sprouting from the burl dome. In the U.K., this growth is referred to as a "Burr," in the U.S. is known as a "Burl." The figure in burrs is one of the most beautiful in the tree and is highly sought after by woodturners. Burr figure can range from tightly packed eyes, to swirling grain with eyes in an almost molten like appearance.

C

CA – Cyanoacrylate Ester Adhesive. Commonly referred to as Alkyl 2-Cyanoacrylates, Super Glue, or CA. Monofunctional 2-cyanoacrylates were first discovered in 1942 during World War II, but were not patented until 1949. 2-cyanoacrylate ester monomer bases are all thin, crystal-clear liquids with viscosities ranging from 1 - 3 mPa’s (=cP). Because the base monomers are very thin, stabilizers, thickeners and other property-modifying additives (soluble polymers and plasticizers) are used to alter the viscosity, physical characteristics, performance and elastification of the formulations.

Thin Cyanoacrylate "Super Glues"

Calipers - Calipers are one of the most ubiquitous tools in a woodturner's studio. Useful for both faceplate and spindle turning, you need a good set of calipers to measure tenons, check the size of recesses, measure lids for boxes, mark major transitions for spindles and a hundred other tasks. Outside calipers have two arms that curve outward and back toward their points. Inside calipers have two arms that have outwardly curved arms at the end of the tool.

Inside and outside woodturning calipers

CAMI - Coated Abrasives Manufacturing Institute - Organization of coated abrasive manufacturers.

Candelilla Wax - Candelilla Wax is a natural vegetable wax found on the outer coating of the Candelilla shrubs Euphorbia Cerifera, Euphorbia Antisyphilitica and Pedilanthus Pavonis. These shrubs grow primarily in the Coahuila and Chihuahuan deserts along the United States - Mexico border. The wax is extracted in the field by heating the plants in water and adding sulphuric acid. The floating wax is then skimmed and filtered.

The colour of the wax ranges from yellow to tan and is slightly tacky. It is softer than Carnauba wax, with a penetration of 3 dmm at 25 degrees Centigrade and a melting point of 70 degrees Centigrade. It is sometimes used as a substitute for Carnauba wax, due to its high gloss and similar hardness characteristics.

Carnauba Wax - Carnauba Wax is obtained from the outer waxy coating of palm fronds from the Copernicia cerifera, the Brazilian Carnauba Palm. The fronds are collected twice a year in September and December. The wax is extracted by separating the wax from the frond with mechanical beaters. Carnauba wax is the hardest natural vegetable wax, with a penetration of only 2 dmm at 25 degrees Centigrade and only 3 dmm at 43.3 degrees Centigrade. It is brittle and non-tacky with a melting point of approximately 84 degrees Centigrade. This wax produces a very high gloss and is frequently used to increase the melting point, gloss level, durability and lubricity of other waxes.

Carnauba wax bars

Cast Iron – An alloy of Iron containing approximately 1.8% to 4.5% carbon. Cast Iron is used on some lathes to form the bedways and headstocks. It is less dense than steel, however its thick castings add weight to the lathe and help to reduce vibration.

Castor Oil - Castor oil is obtained by cold pressing and hexane solvent extraction of the beans from Ricinus communis. The Castor oil is then converted to a drying oil by heating with acid catalysts (sulphuric acid, phosphoric acid, or acidic salts) to form dehydrated castor oil, which contains conjugated octadecadienoic acid isomers. Castor oil ranks between linseed oil and tung oil for film drying and formation characteristics and is frequently used as a base for non-yellowing binders in flexible coatings, due to its lack of trienes.

Catalyst - Various chemical substances that are used to speed the curing of adhesives, sealants or impregnating compounds. Catalysts are sometimes called Accelerators or Kickers.

Centipoise - Centipoise (cP) is a measurement unit of viscosity. It is a mechanical measurement of the resistance of a liquid to flow, where gravity is not a factor. 100 Centipoise = 1 Poise. Examples of viscosity measurements in cP include: Water - 1 - 5 cP, Blood - 10 cP, SAE 10 Motor Oil - 50 - 100 cP, SAE 40 Motor Oil 250 - 500 cP, Honey - 2,000 - 3,000 cP, Chocolate Syrup - 10,000 - 25,000 cP, Ketchup - 50,000 - 70,000 cP, Peanut Butter - 150,000 - 250,000 cP. See Viscosity and Stoke.

Centre Finder - A plastic or metal jig that is used to accurately find the centre of square, round, hexagon, or octagon shaped turning squares prior to drilling.

Centre finder

Centre Saver - A specialized tool with curved knives that is used to remove the centres of bowls as a single block of wood. This saved core can then be remounted, so additional bowls can be turned and saved. Centre savers like the Kel McNaughton Centre Saver can easily save one bowl for every inch of thickness in the rough bowl blank. Thus, a four inch bowl blank can yield four bowls instead of one. Centre Savers are also known as Bowl Savers and Coring Tools.

Three bowls cored using the Kelton Centre Saver

Cerrium Oxide (CeO2) - (~ 8.0 Mohs Scale) A white to reddish brown colored natural abrasive that is used for polishing glass and quartz crystals. Cerrium Oxide may also contain other rare earth oxides like Rubidium Oxide and Tantalum Oxide.

Chatter Marks – A repetitive pattern of cuts, or marks that are left on a finished surface. If the chatter is intentionally created with chatter tools, it is known as Chatter Work, if it is unintentional, it is usually called Chatter Marks. Unintentional chatter marks can be created by using tools that are very thin in cross-section in an unsupported manner, too far off the end of the tool rest.

Check - A separation or fissure in the wood fibers caused by rapid moisture loss, or through tension stresses during drying. Checks are usually found on end grain faces, but may also be found in high figured areas, or in extreme cases, in side grain areas.

Chemical Bonding - The process for joining two or more pieces of wood via a direct chain of covalent bonds between adjacent surfaces.

Chip Clearance - The amount of space in the cut channel produced by a bandsaw blade that allows room for the chip to clear and exit the cut.

Chuck - A work holding/fixing device used to mount a piece of wood firmly onto the end of a spindle. There are many different types of chucks including scroll chucks, screw chucks, collet chucks and pin chucks to name a few.

Closed Coat Abrasive - Closed coat abrasives have abrasive grains covering 100% of the backing surface. The increased density of abrasives on the surface makes these abrasives less flexible than open coated abrasives. Closed coat abrasives offer increased stock removal rates when compared to open coated abrasives.

Close Quarter Drill - A drill that features an angled head design that allows it to be used effectively in close/tight quarters. This type of drill is popular with many bowl turners, since it is ergonomically comfortable to use and offers ample clearance when sanding inside bowls, or deep platters. Also known as an Angled Head Drill.

Neko's close quarter drill

➢ "J" weight cloth – Very flexible and lightweight cloth that works well in contour/tight quarters work. "JF" weight offers extra flexibility. J weight cloths are a good choice for many woodturning needs.

➢ "X" weight cloth – Heavier than J weight, X weight cloths are the most common cloth weight backing and are used on abrasive belts where superior flexibility is not necessary. "XF" weight offers extra flexibility.

Cloth Rolling Embellishment - A specialised finishing technique that is created when a rolled up cloth (or plastic film sheet) is rolled over a wet finish, creating a randomized wrinkled appearance. Rolling is usually performed on glazes, but may be employed with other finishes as well. Also known as Rag Rolling, or Crinkle Rolling.

Coated Abrasive - An abrasive product consisting of three basic materials, the abrasive, a backing material and the adhesive bonding agent.

Coated Abrasive Manufacturing Process - Abrasive grains are held onto a backing material by an adhesive bonding material. The backing material used (paper, cloth, film etc.) acts as a foundation for the primary adhesive, known as the make coat to anchor the abrasive grains onto the backing.

Once the make coat has been applied to the backing, abrasive grains are deposited onto the surface of the make coat by an electrostatic field, or through a gravity fed process. In the electrostatic application process, abrasive grains are loaded onto a conveyor belt as the grains pass through an electrostatic field. This causes the abrasive grains to polarize and align with their elongated ends standing up.

The electrostatic charge causes the grains to jump up onto an overhead belt containing the backing loaded with adhesive. Once the make coat has cured, a second adhesive coating known as the size coat is applied. The size coat functions to securely bond the grains onto the backing material.

Once the size coat has cured, post processing of the abrasive begins. Post processing includes final curing, humidification and with most abrasives, flexing of the rolls. Some abrasives also feature a third coating, known as the top size, or super size. This is applied after the size coat has cured and carries lubricants such as Zinc Stearate, which reduces friction and loading of the surface when sanding.

Cobwebbing - The tendency of spray paint to produce hair-like strands, or strings of paint as it leaves the tip of the spray gun. These strands produce the visual effect of a cobweb, or spider's web. This defect can be produced by using too little air pressure, or by using a solvent that is too volatile.

Cohesive Forces - Forces that exist between molecules of the same material.

Cold Flow - Creep at ambient temperatures. See Creep.

Collet Chuck (Precision) - A very accurate woodturning chuck that is used for holding circular dowels, pen mandrels, tenons, or finials on a lathe without marking. Most collet chucks have a very small range of movement, typically 1/32" and are available with 5 collets ranging in size from 1/4" - 3/4."

The Beall Collet Chuck

Colour Rendition Index - A measurement of the way a light source renders colour. Expressed as CRI, the higher the CRI number, the closer the colour will resemble how it will actually appear when viewed in sunlight.

Colour Wheel - Colour wheels are visual aids that teach color relationships by organizing the colors into a circle, which makes it easier to visualize how they relate to each other. Most colour wheels include the primary colours red, yellow and blue, secondary colours green, orange and purple, and the tertiary colours yellow-orange, red-orange, red-purple, blue-purple, blue-green and yellow-green, as well as show analogous and complementary colours.

A basic colour wheel is great to have on hand when colouring woodturnings

Compressive Strength - The ability of a metal to withstand pressures that are acting on a given plane.

Compressor Receiver - The primary containment tank or reservoir used to store gas under pressure.

Concave - Curving Inwards.

Cone Center - The cone shaped end on a tailstock center that is used to support one end of the work piece. Cone centers are frequently used to support the neck end of vases and the cup end of goblets when rechucking to finish off the foot area.

Conjugated Oils - Conjugated oils include oils such as tung, oiticica, dehydrated castor oil and isomerised nonconjugated oils. Conjugated oils are polyunsaturated fatty acids whose double bonds are partly, or fully conjugated (i.e. alternate single and double bonds in the carbon chain are the fatty acids).

Conventional Spray Gun - An air atomizing spray gun that passes virtually all of the input pressure to the air cap. Conventional spray guns are not as efficient as an HVLP (High Volume, Low Pressure) spray gun.

Convex - Curving outwards.

Copy Turning - The process of duplicating a turned form with multiple replicas. Jigs or cut-out templates are frequently used to insure an exact match on the replicated turning.

Corundum - (~ 9.0 Mohs Scale) A naturally occurring Aluminum Oxide abrasive that is mined from the earth. Corundum has a softer crystalline structure than Silicon Carbide and synthetic Aluminum Oxide abrasives.

Crazing - Hairline cracks or fissures that appear in, or on the surface of polymer networks, or adhesives.

Creep - 1.) The seepage of wax from sealed tins, normally referred to as Wax Creep. 2.) A dimensional change that can occur over time with materials under load, following rapid or instantaneous deformations, especially after repeated cycling. See Cold Flow.

Crotch Figure - One of the most beautiful parts of a tree, crotch figure is found at the intersecting "V" where two limbs join. Crotch figure is sometimes referred to as Crotch Feather, since the figure appears much like a feather turned upside down. In larger limbs, the feather figure can be exquisite, with numerous delicate colours and an almost metallic chatoyance in the grain figure.

Crotch Wood - Wood that is located directly under the fork of a tree limb. When sawn parallel to the piths, a magnificent crotch feather figure is revealed. Crotch figure is among the most prized of all wood figure in the woodturning world.

Crowning A defect in wood with a convex appearance, where the centre of the board is higher than the edges of the wood.

Crushed Stone Inlay - Any area on a woodturning that has been filled and sanded smooth that contains crushed stones. Crushed stone inlays typically use Cyanoacrylates, or binary epoxies as the binding adhesive. Crushed stone is a popular embellishment for woodturning projects. In addition to being used to fill a void, crushed stones may also be used to create banded inlays, or to create specific scenes.

Olive wood hollow form inlaid with Turquoise crushed stone

Cup - A type of warp evidenced by a deviation from a flat surface across the width of the board.

Cupping - A defect in wood with a concave appearance where the edges of the board are higher than the centre.

Cup Centre - (1) The standard centre point used for most ball bearing live centres. Cup centres feature a sharpened ring around the outside of the centre point. This ring acts as a binding ring to prevent the centre point from creating a split in the end of the blank. (2) A hollow center point mounted in the tailstock that is used to centre a lamp auger for drilling a lamp vase.

Cure Time - The amount of time necessary for an adhesive to reach maximum strength. This will vary with the type of adhesive and the specific environment.

Curing Agent - A chemical substance that is used to speed the curing of adhesives and sealants. Also known as a Catalyst, Accelerator or Hardener.

Curved Tool Rest – A special tool rest that features a curved design for use with bowls and other deeply contoured projects. Curved tool rests allow the tool to be positioned closer to the surface of the wood for greater control. Curved tool rests can be made from cast iron, or steel and are available in various lengths and degrees of curve. Some curved tool rests feature a double curved "S" design for working on the interior as well as the exterior of bowl forms.

Cutting Waxes - A light wax that contains an ultra-fine abrasive compound. The wax acts as a carrier, allowing an efficient method to apply the compound onto the surface and assists in producing an even cut. Cutting waxes (also known as deluxing waxes) are less aggressive than cloth buffing wheels when used for cutting back cured film finishes.

Various cutting waxes

Cyanoacrylate Esters - Cyanoacrylate adhesives typically contain stabilizers, thickeners, soluble polymers and plasticizers to alter the viscosity, physical characteristics and performance of the formulas. Cyanoacrylate polymers spontaneously form via anionic reaction mechanisms, when their liquid precursors or monomers come into contact with a weak base, forming a high molecular weight thermoplastic material. CA's are used for bonding dense substrates in the electronics, watch making, engineering, plastics and rubber industries. In woodturning, CA's are used as a binder for crushed stone and other inlays, for filling voids, making quick glue blocks, securing parts in project kits and a thousand other uses.

Woodturning Glossary - Quick Jump Alphabet Selector

Woodturning Glossary D through F

D

Dead Centre – A non-revolving centre that is mounted in the tailstock's ram. Since dead centres do not rotate at all, they must be lubricated or friction and heat will cause the blank to smoke. Dead centres are rarely used since the advent of revolving ball bearing live centres.

Debonder - A chemical solution that typically contains Acetone, or gamma Butyrolactone that's used for softening, or removing cured CA from skin and other surfaces. De-bonders will damage most finishes and cannot be used to thin CA’s. Although de-bonders can also be used to separate CA bond-lines, it is a slow process because the de-bonder has to work its way through the entire bond-line.

Various CA Debonders

Denatured Alcohol - Denatured Alcohol is pure ethyl alcohol, combined with small amounts of methanol and other chemicals to make it highly poisonous. Contains Ethanol, Acetone, Methanol and Methyl Isobutyl Ketone, Ethyl Acetate, Gasoline or other denaturing agents. Denatured Alcohol is a clear, colourless liquid used as a thinner for shellac based primers to improve levelling, reduce application viscosity and improve penetration. Shellac thinned with denatured alcohol gives a smooth, high gloss film with improved working consistency. Denatured alcohol will also soften and remove dried shellac. It is not compatible with oils or latex paints, stains or varnishes. Denatured Alcohol is sometimes referred to as DNA by some woodturners when referencing its use in a wood drying protocol that uses Denatured Alcohol, although the acronym is technically incorrect.

Denatured Alcohol

Detail Sanding – Sanding small decorative elements, or areas on projects that are difficult to reach. Detail sanding can be performed manually with abrasive strips, or with powered detail sanders like a pen, or band sander.

Detail Sanders – Small scale powered sanders that are used for tight quarters sanding. Detail sanders are available in electric and pneumatic versions and include small rotary, random orbit and in-line sanders.

Diamond Abrasives – (10 Mohs Scale, 8000 Knoop Scale) The hardest known substance, diamond abrasives are made from carbon and are manufactured using natural diamonds, or man-made diamonds. Industrial diamonds occur as three main types – Bort (single crystal fragments not gem quality), Ballas (spherical masses of crystals) and Carbonado (an impure form of diamond).

3M's - 3" 250 micron diamond abrasive disk

Diamond Dresser - A diamond based dressing tool that is used to clean and true the face of dry grinding wheels. There are several styles available, but most feature a “T” shaped head that contains diamond chips embedded into the metal face. The dresser is used in conjunction with a flat tool rest and is swept back and forth across the face of the grinding stone (whilst running), to clean and true the face of the stone. In addition to the multi-chip style of dresser, single point diamond dressing tools are also available.

Multi-chip "T" style diamond dressing tool

Diamond Hone - Specially shaped metal plates that feature industrial grade diamonds of various sizes bonded to the surface. Diamond hones are frequently used to improve the edge quality of woodturning tools and may be sized for hand held, or bench mounted operation. Honing may be performed on the sharpened edge straight off the grinding wheel, or in between sharpening, as a way to prolong the edge life and reduce overall wear on the tool by limiting its use on the grinding wheel.

Hand held diamond hones

Diamond Parting Tool – A parting tool featuring a shaft that has been ground along its full length to provide clearance on the upper and lower half of the tool. When viewed from the cutting edge, the cross section of the tool resembles a diamond shape. This shape offers less metal on the side of the shaft to rub against the wood when making deep parting cuts on spindles.

Dig-In– An oopsie, gotcha, or a catch. Dig-ins are an unintended result usually caused by loss of tool control during a cut, causing the tool to cut deeply into the surface of the wood. Dig-ins can produce deep scars and gouges on the wood surface requiring extensive sanding, or re-turning.

Diluent - Ingredients that are added to adhesives to reduce the concentration of active bonding ingredients to alter the flow characteristics of the formulation, or to lessen the overall manufacturing costs.

Dividers – A spring loaded measuring tool with two straight arms and pointed ends that are also known as straight calipers. Dividers are frequently used for checking the spacing of design elements on woodturnings, marking the diameters of spigot bosses and checking layout measurements on pre-drawn plans.

Dovetail Jaws – A specific jaw design for woodturning chucks that features a dovetailed shape on the interior and exterior of the jaws. On scroll chucks that work in both expansion and contraction mode, dovetail jaws allow the chuck to grip interior dovetail recesses (expansion mode), or exterior dovetail spigots (Compression Mode).

Dovetail Recess - An internal recess turned with an angled undercut edge made to fit the dovetailed jaws on a scroll chuck used in expansion mode.

Dovetail Spigot/Boss - An externally turned spigot with a dovetail shape that is used as the mounting point for a scroll chuck when used in compression mode.

Dowel Chuck - A special type of Jacob's chuck used for turning small dowel mounted projects like bottle stoppers. Unlike a traditional Jacob's chuck jaws that only grip a dowel in three places around it's circumference, a dowel chuck grips around the entire circumference of the wooden dowel because the interior jaws have been drilled out to accept 3/8" or 10 mm dowels.

Driers - Driers are oil soluble metal salts of organic acids. When these driers are dissolved in aliphatic or aromatic hydrocarbons, they are known as siccatives. When driers are added to drying oils, they are known as Boiled Oils. Traditionally, driers contained combinations of oil-soluble metal salts like Cobalt and/or Manganese with Zirconium, Lead or Calcium salts of 2-ethylhexanoic acid, or naphtenic acids. Cobalt and Manganese salts act as surface driers and aid in the drying of the film on the surface, where oxygen concentrations are the highest.

Lead and Zirconium salts catalyze throughout the film and are known as through driers. To avoid the use of Lead, which is highly toxic, modern siccatives employ blends of Cobalt and Zirconium. This combination reduces surface drying speed, promoting even drying throughout the substrate. Calcium salts are sometimes used as well, mainly to reduce the amounts of other driers that may be needed. Various other compounds may also be present in some siccatives including Beryllium, Cadmium and Nickel.

Drill Chuck – A non-rotating Jacob's chuck fixing that holds twist drills, Forstner bits and spade bits for drilling holes in blanks on the lathe. Drill chucks may be mounted in the headstock or tailstock for drilling and feature a Morse taper arbor.

Drilling Jig - Any device that is used as a guide for locating/drilling holes in woodturnings. Drilling jigs allow for precise hole locations at different points on a woodturning. An example of a drilling jig is Kelton's Ornamental Jig, which can be used as a drilling jig, or with other tools to carve and sculpt the wood surface.

Drive Centre – Drive centres are a 2-prong or 4-prong Morse taper drive center with sharp blades that cut into the surface of the wood to drive it during turning. Drive centers must be used with a tailstock center support. Drive centers are used to mount and turn spindles and to roughout the back (bottom) of bowls, platters and hollow forms to prepare them for mounting in a scroll chuck.

Two prong and four prong drive spurs

Drying Oils - Drying oils, including linseed and tung, can be defined as liquid vegetable oils that when applied in thin layers to a non-absorbent substrate, will dry in the air to form a solid film. This drying is a result of polymerization by the action of atmospheric oxygen, i.e. autoxidation.

Drying Process -(Oil Finishes) - The drying of films typically progresses in three overlapping steps:

1.) Induction - Through a process known as autocatalysis, the oxygen uptake, which is slow at first, steadily increases. Factors such as temperature, light and heavy metals/inhibitors in the oil affect the overall uptake rate.

2.) Initiation - As the film continues to take up oxygen, its mass increases. The double bonds in the film begin to rearrange and polar groups such as hydroxyl and hydroperoxy develop in the film. This leads to the association of molecules, through forces such as hydrogen bonding.

3.) Cross-Linking - As the number of double bonds in the film begins to diminish, larger molecules form, and volatile and non-volatile carbonyl compounds are generated. The exact chemical reactions, as well as the structure of the film-forming polymers, are not completely understood. The initial autoxidation step in nonconjugated oils is dehydrogenation of the unsaturated fatty acid by molecular oxygen, which forms a radical. This starts a catalytic radical chain reaction that increases incrementally with time, leading to the formation of a hydroperoxide.

At low levels, the hydroperoxides produced during autoxidation decompose to form free alkoxy and hydroxyl radicals. Higher levels of hydroperoxides form free radicals through biomolecular disproportionation. The resultant free radicals react in various ways to accelerate the autoxidation process.

The drying of tung oil varies considerably from linseed oil. Tung oil typically absorbs approximately 12% oxygen (linseed oil absorbs approx. 16%) and quickly forms a skin on the surface. Since less oxygen is absorbed, the viscosity of the oil increases at a faster rate. Unlike the hydroperoxide formation during autoxidation in linseed oil, tung oil forms cyclic peroxides. The methyl eleostearate that is formed has a higher molecular mass than linoleic acid esters.

The direct attack on the double bonds by oxygen forms cyclic peroxides. The resultant reaction of the peroxides with allylic methylene groups, leads to the formation of radicals. This creates a radical chain reaction that forms polymers. The molecular mass created during tung oil polymerization is less than that achieved through linseed oil polymerization. To speed up the film formation and curing process, manufacturers add “driers” to the oils.

Ductility - The ability of a metal to be stretched permanently without rupture or fracture.

E

Elasticity (Metal) - The ability of a metal to return to its original shape when it has been stretched out of shape.

Emery – (~ 7.5 – 8.5 Mohs) A dark grey, blocky shaped impure form of Corundum, a natural Aluminum Oxide and mineralized Iron Oxide. The use of Emery abrasives has been largely replaced with newer high-performance synthetics.

EMC - Equilibrium Moisture Content, or EMC is defined as the point at which the moisture level inside the wood has reached equilibrium with the moisture level in its ambient storage environment. The EMC level will vary according to the moisture level in the surrounding air.

End Check - A split, crack or fissure in the end grain portion of a log, blank or turning square.

End Grain - The portion of a cut piece of wood that has been cut across the grain, instead of in-line with the grain. On a cut log section, the end grain is revealed by cutting directly through a log, creating a "round." The resulting figure looks like concentric circles on the end grain faces.

Endothermic - Chemical reactions that require heat to proceed. End Sealer - Cold wax emulsion products that are painted onto the endgrain of logs and blanks to reduce checking. Anchorseal, (a popular end sealer) is a paraffin based colloidal solution that contains paraffin, water and a surfactant and is milky-white in appearance. In the woodturning workshop, end sealers serve an important function by controlling the rapid loss of moisture through the end grain of logs, blanks, turning squares and roughed out bowls.

Applying Anchorseal end sealer to a green wood log

Epoxy (Polyepoxide) – Epoxy adhesive resins are usually based on the diglycidyl ether of bisphenol-A, or bisphenol-F. Two-part epoxy resins polymerize (cross-link) to form thermoset polymers, when covalent bonds between the resin and the hardener form, through the reaction of the epoxide ring with the ring opening species on the hardener. Different types of hardeners are used, depending on the specific epoxy. Epoxy adhesives are used to adhere wood, metals, glass, fiberglass, plastics, rubber and ceramics. In woodturning, epoxies are used for segmented constructions, bonding project blanks, as a binder for inlays, for waterproofing vessels and for gluing metal tubes into project blanks.

Exothermic - Chemical reactions that release heat.

Exotic Timber - Timbers that are imported, versus those that are grown in the country where you live. Many times, exotic timbers represent rare, or slow growth timbers from different parts of the world. Some are also common timbers from various parts of the world that are exported.

Extenders - Ingredients that are added to adhesives to reduce the cost of the primary adhesive components. Extenders may or may not have any adhesive properties.

External Mix Spray Gun - A spray gun that atomizes the finishing material and the air outside the cap. External mix spray guns are frequently used for spraying fast drying finishes like lacquer.

F

Faceplate - A circular shaped mounting/fixing plate that is secured to the headstock spindle for mounting blanks on the lathe for turning. Faceplates feature numerous holes that are drilled through the plate for attaching blanks to the faceplate with wood screws. Faceplates may be made from cast iron, steel, or aircraft grade aluminum and come in many different sizes ranging from 2" to more than 12" in diameter.

Oneway's 10" cast iron faceplate threaded 33 x 3.5mm

Faceplate Ring - A special type of removable faceplate with a large centre hole, that looks like a ring. Faceplate rings are designed to be used in conjunction with an expanding four jaw chuck. Once the ring has been screwed to a blank, it can be mounted on a chuck for turning. If necessary, it can be removed from the chuck and remounted at a later date. Since the chuck jaws are bearing against a metal surface, the axis of rotation is preserved when mounting and dismounting.

Faceplate Turning - A term that describes the turning of projects like bowls or platters where the grain is usually at right angles to the axis of the lathe. Faceplates are typically used without tailstock support for some or all of the turning process.


Fairing The Curve - An expression that relates to sweetening or perfecting the shape of a curve on a woodturning project. Also known as Sweetening The Curve.

FAQ - An abbreviation for "Frequently Asked Questions." FAQ's are used to provide answers to frequently asked questions on Internet websites, such as billing practices, shipping methods, registration information etc.

Feed Pressure - The amount of force required to push a project blank into a bandsaw blade to produce a cut.

Feed Rate - The cutting speed that a bandsaw blade achieves as it cuts through the project material. This speed is usually expressed in terms of the amount of inches per minute completed during the cut.

FEPA - Federation of European Producers of Abrasives - European organization that maintains abrasive specifications (FEPA F - Bonded) (FEPA P - Coated).

Flap Wheel - An abrasive product consisting of multiple flat pieces of coated abrasive sheets called flaps, that are arranged on a mounting like the spokes on a wheel. When the flap wheel is mounted in a rotary tool, the flaps spin around and abrade or polish the surface of the material. Flap wheels are available in many different configurations including star shapes, crosses, and multiple cut strip sheets that are usually mounted onto a small arbor for use with rotary tools.

Klingspor's arbor mounted abrasive flap wheel

Figure - The visual grain and features on the surface of cut wood. The amount and type of figure present in wood is dependent on many things including how and where the tree grew, how the wood was cut (flat sawn, endgrain, quartersawn, etc.), the distance between growth rings, colour variations in the wood, special growth characteristics like knots, overgrown branches, burr formations, curl, and fugal rot or decay to name a few.

Filler - Ingredients added to adhesives to improve the specific performance properties of an adhesive, such as durability, hardness, strength or stability.

Film Backed – Mylar as well as other types of films are used for film backed abrasive papers. The primary advantages of film backings include extreme flatness and flexibility and they are naturally waterproof.

Fixture Time - The amount of time before bonded adhesive parts can be handled.

Flap Disc Sander - A specialised abrasive product consisting of multiple abrasive flaps mounted on an arbor with a hard phenolic resin based backing plate. Flap disc sanders are typically used on high speed angle grinders.

Flint (Quartz Sand) – (~ 7.0 Mohs) A natural non-conductive silica based microcrystalline quartz mineral that is grayish white in colour. Quartz features a hexagonal structure, with distinct rhombohedral cleavage and conchoidal fracture characteristics.

Floating The Bevel - A specialized cutting technique where the bevel of the tool barely touches the surface of the wood as if it's floating over the surface during the cut. This cut requires a good deal of finesse, since the quality of the cut is largely determined by the smoothness and accuracy of the turners body movements.

Fluid Texturing - A high speed surface texturing process developed by professional woodturner Steve Russell of Eurowood Werks Studio that uses high speed power carving tools to texture and carve projects on the lathe, whilst the project is in motion. The textures created by this process add a unique visual and tactile allure to the piece that is difficult, if not impossible to attain by other methods.

Bimini Hut texture created with the Fluid Texturing Protocol

Flutter - A condition on bandsaw blades where the blade moves rapidly from side to side. Bandsaw blade flutter is typically caused by incorrect tension (too little) on the band, or by worn springs in the bandsaw that are incapable of producing the correct amount of tension due to metal fatigue or wear.

Flyspeck Embellishment - A specialised finishing technique that is created when a colour or other finishing material is flicked off a brush creating randomised dots in varying size and intensity. Flyspecking can be easily performed using old toothbrushes, or similar stiff bristle brushes.

Foam Backing – Various densities and thicknesses of foam backings are used for abrasive sponges that range from flexible to very stiff.

Forstner Bit - A special type of slow speed drilling bit that drills flat bottomed holes.

Four Jaw Chuck - The mainstay work holding chuck for woodturners. Four jaw chucks are more commonly called scroll chucks because of the spiral-grooved mechanisms that move the jaws in and out. Four jaw chucks are self-centering, unlike some metal chucks whose jaws must be independently centered on the workpiece.

Friability - The ability of an abrasive grain to cleave easily along weak crystallographic planes, producing new sharp fracture facets.

Friction Wax - A solid block, stick or bar of wax that is used to apply a wax finish to small items on the lathe. Hand held friction waxes are applied, whilst the piece is rotating at a relatively high speed on the lathe. A small amount of wax is melted onto the surface by friction and is immediately buffed with moderate pressure to produce the desired gloss lustre.

Wax friction sticks are melted onto the surface, then buffed

Woodturning Glossary - Quick Jump Alphabet Selector

Woodturning Glossary G through I

G

Garnet – (~ 7.5 – 9.0 Mohs) A naturally occurring, very sharp dark reddish brown coloured abrasive grain made from semi-precious Garnet stones. Of the seven species that exist, Pyrope (a Magnesium Aluminum Silicate) and Almadine, (an Iron Aluminum Silicate) dominate in abrasive manufacturing.

Gelation - The process whereby a liquid thickens and changes into a solid.

Glass Transition Temperature - (Tg) is the temperature point where a polymer experiences a significant change in properties. For example, when heated the polymer may turn rubbery, upon cooling it may turn glassy.

Glue Bond Systems - Animal hide based glues (with and without fillers) are used for some glue bond based systems. Although glue bond systems offer more flexibility than resin bond systems, they are not as resistant to heat buildup and tend to soften when heated. The softened glue can then act as a cushion, lowering the overall cutting efficiency.

Glue Gun - A small handheld, pistol shaped hot glue dispenser. Glue guns are used with various types of solid glue sticks. Long tubes of glue are loaded into the rear of the gun and the gun heats the glue to the proper temperature. Once the hot glue is needed, the trigger is pulled and the gun forces the glue out through a small nozzle on the front of the gun. Also known as a Hot Melt Glue Gun. Glue guns are popular for making up glue chucks and glue blocks, prior to turning on the lathe.

Glue Line - The line at which the material and the adhesive meet in an adhesive binding.

Gluing Up - The process of gluing timber together using adhesives.

Gouge - A woodturning cutting tool that features a curved "U" shaped flute, or a rounded bottom "V" shaped flute. Modern gouges are made from round tool steel blanks with ground flutes of varying shape and depth. Typical examples include roughing gouges, shallow fluted spindle gouges and deep fluted bowl gouges.

Gravity Fed Spray Gun - A spray gun that uses gravity to move the finishing material from the reservoir/cup into the gun for spraying. Gravity fed spray guns have a cup mounted above the gun and use no pickup tube. Gravity fed spray guns use less air than suction fed guns and are great for small jobs, touch-up work, or when working with multiple finishes on different projects.

Green Rouge (~ 8.5 Mohs Scale) A rouge made from Chromium Oxide that is used to polish hard materials like stainless steel and chrome plating, as well as some plastics.

Green Timber - Fresh cut wood that contains a very high moisture content and has not been dried by any process. Green timber is preferred by many woodturners because of its availability and low cost.

Green Time - The period of time between the application of an adhesive the substrates and it's solidification. Also known as Open Time, or Working Time. During this time, the components may allow limited repositioning.

Green Turning - (1) Woodturnings that incorporate the use of salvaged, reclaimed, or waste timber for the source of the project blank. (2) Woodturnings that have been turned in one step from the green log to the finished project and allowed to warp naturally. Some turners refer to this style of turning as "Natural Turning." (3) Woodturnings that are roughed out from the green log and allowed to dry by various means. Once the roughout has dried, it is remounted on the lathe and any warp is turned away as the project is finish turned. This style of green turning is typically referred to as "Two Step Turning."

Grinding Wheel - A bonded abrasive product that is shaped into round wheels of varying size and width that are used on slow and high speed grinders. Grinding wheels are made from numerous abrasives including Aluminum Oxide, Silicon Carbide and Seeded Gel "SG" Ceramic abrasives. In addition, Cubic Boron Nitride and Diamond based abrasives are also available in specialised grinding wheels.

Growth Rings - Concentric rings that are formed each year as the tree grows. Wood that grows in the spring (springwood) is usually lighter in colour and density than the wood that grows later in the summer (summerwood).

Gum Turpentine - Gum Turpentine (Also known as Spirit of Turpentine, Oil of Turpentine and Wood Turpentine) is pure essential plant oil, which is obtained by distillation of the resin exudates (balsam or turpentine) from living trees in the genus Pinis. Contains Terpenes. The resin exudates are distilled at temperatures up to 180° Centigrade. It is a high quality paint solvent, which is stronger than paint thinner and dries at a slightly faster evaporation rate. Turpentines are colourless to pale yellow liquids, with a low viscosity and a characteristic odour. Turpentines are miscible in most organic solvents, but are immiscible in water. Sometimes referred to as Turps.

Pure Gum Turpentine

Half Mask Respirator - A non-powered, personal protection device (PPD) that covers your mouth and nose to protect against the inhalation of various dusts. Some half mask respirators can also be fitted with special cartridges that offer protection against certain fumes.

Half mask respirator with P-100 dust filters and organic vapor cartridges

Hardener - Chemical substance/s that are added to adhesives to initiate the curing reaction. For example, the second part of a two-part epoxy.

Hardness - The ability of a metal to resist penetration and wear by another material, or metal. The hardness of a metal is typically controlled by special heat treatments during manufacturing.

Headstock - The housing containing the spindle and the spindle support bearings. Most woodturning lathes feature spindles with Morse taper arbors.

Heartwood- The older part of the log that extends from the pith to the sapwood boundary. Heartwood cells are usually darker in colour than sapwood and are nonliving, contributing no life processes in the tree.

Hiccuping - If the lathe speed is set too fast when using a Random Orbit Sander (ROS) on the lathe, the ROS pad will stop spinning and skip around on the surface. This condition is known as hiccuping. To prevent hiccuping, set your lathe revs to a very slow RPM, or use your ROS on the project with the lathe turned off.

Hide Glue (Scotch Glue) - Hide glue is a protein-based adhesive made from the hide or bones of cattle, with collagen being a primary ingredient. Hide glue is popular with musical instrument makers and period furniture builders, as well as some woodturners for built-up constructions and segmented work.

High Speed Grinder - A bench mounted electric grinder that features two grinding wheels, one on each end of the drive shaft. High speed grinders typically turn at ~ 3,450 RPM. When equipped with the proper abrasive wheels, high speed grinders are popular tools for sharpening woodturning tools either freehand, or with a manufactured sharpening jig. High speed grinders come in many different sizes however, 6", 8" and 10" grinders are the most useful for woodturners. Eight inch grinders are the most common size used for sharpening.

High Speed Steel - HSS - One of the primary steels used to make woodturning tools. HSS contains various alloys including Carbon, Chromium, Tungsten, Molybdenum, Vanadium and Cobalt. HSS exhibits a high hardness and wear resistance. The base specification for HSS woodturning tools is known as M2 – HSS, which typically contains 0.83% Carbon, 4.15% Chromium, 6.15% Tungsten, 5.10% Molybdenum, 1.95% Vanadium, with the balance being composed of iron.

Hollow Forms - Woodturnings that feature an opening that is smaller than the maximum diameter of the project, for example a decorative urn or flower vase. Hollow forms are turned with special hollowing tools called boring bars that may be captive (lathe mounted), handheld (armbrace style), or used freehand.

Spalted Water Oak hollow form

Hook Tool - A specialised turning tool that features a cutting tip that looks like a hook, with a sharpened edge. Hook tools are favored for end grain hollowing projects by some turners.

Kel McNaughton hook tools

Hot Batching - Preparing a two-part adhesive, or finish with slightly more catalyst than the manufacturer recommends. The opposite of hot batching is known as Cool Batching, which is preparing a two-part adhesive, or finish with slightly less catalyst than the manufacturer recommends. These techniques are sometimes used based on ambient temperature, humidity or surface conditions, or to speed or slow the curing of the product to produce a better end result.

Both hot batching and cool batching are a dance with potential failure, as varying from the established recommendations can result in incomplete curing, or damage to the adhesive/finish from too much heat, or other induced defects. Do not attempt these techniques unless you are an experienced professional that is well versed with the nuances of altering the recommended amount of catalyst.

Hot Melt Adhesives – Hot melt formulations are based on various polymers including ethylene-vinyl acetate, a random copolymer of vinyl acetate. Adhesion is provided by a combination of low glass transition, low to no crystallinity and high polarity of acetate groups. Hot melts are a 100% solids adhesive that requires heat to raise the temperature to a workable viscosity. Upon cooling, the adhesive re-solidifies creating a bond. Conventional hot melts do not chemically cross-link when cured. Newer polyurethane reactive hot melts undergo cross-linking, when residual isocyanate groups react with water after application, creating a thermoset adhesive. Used for light bonding of wood, metal, plastics and laminates.

HVLP Spray Guns - High Volume, Low Pressure (HVLP) spray guns use a high volume of air (usually 15 - 26 CFM) at low pressures (10 PSI or less at the cap) to atomize finishing materials into a low velocity, soft spray. The design of HVLP guns produces a greater transfer efficiency than conventional spray guns, resulting is less overspray, blowback and bounceback. HVLP systems are popular for spraying many types of stains, dyes, urethanes, acrylics, epoxies, lacquers and two-part finishing products on woodturnings and are less expensive to use compared to conventional guns because of their greater transfer efficiency.

Hygroscopic - Something that can readily absorb, or release moisture from the air. Wood is hygroscopic in nature, as it can absorb and release moisture from the air with seasonal, or environmental changes.

I

Inboard Turning - Woodturning projects that are turned over the bed of the lathe, to the right hand side of the headstock.

Incremental Penetration Hollowing - A well proven technique to hollow and sand the interior of thin walled bowls through successive increments, one inch at a time. In traditional bowl hollowing, the bowl gouge is swept from the rim to the bottom of the bowl, in one continuous fluid pass.

If this technique is used when turning thin walled bowls, the walls may flex during turning, which may lead to tear out on end grain surfaces. Incremental penetration hollowing effectively controls harmonic vibration and thin wall flexing, allowing thin walled bowls 1/16" thick or less to be easily turned. This technique is also known as Incremental Step Hollowing, or Step-by-Step Hollowing.

Inertia Sander - A passive (non-powered) sander that rotates by contact with a spinning workpiece. Passive sanders are a popular choice with many bowl and platter turners and are also frequently used on hollow forms. Inertia sanders are very quiet in use and allow deep sanding inside hollow forms where other (powered) sanders have difficulty reaching.

The Sanding Solutions inertia powered sander features a fully articulated head and precision ball bearings.

Index Wheel - A precisely machined, graduated wheel with positive stops that is used on wood lathes to assist with the layout of decorative design elements. Index wheels are divided into numerous equal divisions for example 48, or 96 stops. A fluted table leg is an example of a project turned with the aid of an index wheel.

Oneway 2436, 48 stop index wheel

Inhibitor - Ingredients added to adhesives that retard chemical reactions. Inhibitors may be used for numerous reasons, such as increasing the working time to make application easier, or to increase the shelf life of a product. Also known as a Retarder.

Interface - The two-dimensional plane of contact between the surface of one material and the surface of the other material.

Interface Pad - A hook and loop faced foam pad that is mounted between the front face of a sanding mandrel and the back of an abrasive disk. Interface pads are popular with woodturners because they save wear and tear on expensive power sanding mandrels. Interface pads allow you to change the density of the foam sanding mandrel to suit specific needs by using a different density interface pad. Interface pads are called backing pads by some manufacturers.

Various hook and loop faced interface pads for power sanding

Internal Mix Spray Gun - A spray gun that mixes the finishing material and the air inside the cap, before spraying them through the cap. Internal mix caps are typically used with slow drying materials that require low pressure.

Interphase Region- The three-dimensional volume of material between the adhesive and the adherend. The physical and chemical properties of the interphase region play a critical role in the quality of the adhesive bond.

Isocyanate – Compound containing the functional group N=C=O, attached to an organic radical or hydrogen. Isocyanates are cross-linked with hydroxyls to form polyurethanes.

Woodturning Glossary - Quick Jump Alphabet Selector

Woodturning Glossary J through L

J

Jacob's Chuck - A type of drill chuck that can be used in the headstock, or tailstock of a lathe. Jacob's chucks are typically used for holding drill bits during drilling operations, but may also act as a fixing when used to secure sizing mandrels for turning small projects.

Jig - Any device made to facilitate an operation such as drilling, sanding, grinding, sharpening, milling, finishing, or sawing.

JIS - Japanese Industrial Standard, published by the Japanese Industrial Standards Committee in conjunction with the Japanese Standards Association.

K

Kauri-Butanol Value The specific measurement of a hydrocarbon solvents strength, expressed as KB. All other things being equal, the higher the KB value, the stronger the solvent.

Kerf - The width of material that is removed by a different types of saw blades (bandsaw, tablesaw, reciprocating saw, handsaw, coping saw etc.) as they complete the cut.

Kicker - A chemical "accelerator" that speeds the curing process of Cyanoacrylates, or Super Glue. Kickers utilize amines as the active ingredient and are available from most Cyanoacrylate suppliers. Kickers are typically applied by spraying, dipping, or wiping the accelerator onto an adjoining substrate, or over an exposed CA filet. The specific base used varies by product and manufacturer, but may include Isopropanol, Heptane, Acetone, Electronic Grade Acetone, Perfluorocarbon, or Propylene based Glycol Ether. In addition to speeding the curing of cyanoacrylates, kickers also work to effectively clean and degrease the substrate prior to application of the liquid CA.

Various kickers for Cyanoacrylate "Super Glues"

Kiln Drying - A wood drying process that reduces and stabilizes the moisture content of green wood by placing it in temperature controlled ovens, where excess moisture is removed by specific heating protocols. Kiln drying greatly reduces the time required for green wood to reach equilibrium moisture content, or EMC. When green wood reaches EMC, it is said to be "seasoned."

Knopp Hardness Test - A hardness test that applies a known load for a specific amount of time to the surface of a metal, through a diamond with uneven longitudinal and traverse included angles. The Knopp hardness number is the applied load, divided by the unrecovered projected area.

Krebs Units A measurement of viscosity obtained when using a Stormer viscosity instrument. Values are expressed as KU.

L

Lace Bobbin Drive - A metal drive with a tapered square recess that is used in the Morse taper of a spindle, to turn lace bobbin blanks for turning.

Lacquer Thinner - Lacquer Thinner is a clear, colourless blend of solvents formulated exclusively for use with most lacquer based wood and metal finishes. It is not compatible with acrylics, automotive or other specialty lacquers. Contains Isobutyl Isobutyrate, Methyl Ethyl Ketone, Butyl Acetate, Methanol, Toluene, Lactol Spirits, Cyclohexane, Heptane and Methyl Cyclohexane.

Lacquer thinner is a high-strength solvent that is used to thin lacquer based paints and clear finishes to improve levelling and reduce application viscosity, without compromising clarity or gloss.

Lamp Auger - A specialized long drill bit made to drill holes in lamps for the electrical cord pathway. Lamp augers are used in conjunction with a hollow tailstock guide that centers the bit for drilling through the lamp base.

Layout Templates - Clear plastic templates printed with concentric circles that are used to layout, or plan the cutting of bowl and platter blanks. The clear plastic allows easy positioning to find the best figure in the blank, or to eliminate any unwanted defects.

Layout template

Lightfast - The ability to maintain colour (or to withstand colour change) when it's exposed to light. When working with wood dyes, the lightfastness of the dye can be an important consideration, if the completed project will be exposed to natural sunlight.

Light Reflectance Value - A numerical value of the amount of light that is reflected off a dry film coating when using a gloss meter. Commonly expressed as LRV.

Load - The amount of force that a joint, board or body can sustain.

Loading – Term used to describe the accumulation of resins, saw dust or finish on the surface of an abrasive product. Loading greatly reduces the efficiency of the abrasive and adds unnecessary heat to the surface of the abrasive and the surface being sanded.

Load Time - The period of time on an air compressor from the time it loads until it unloads.

Locking Adhesives - Adhesives that are used to prevent threaded screws and similar fasteners from loosening through vibration in use. Anaerobic adhesives are a typical example of this type of adhesive. Commonly referred to as Thread Lockers.

Linseed Oil - Linseed oil, a primary ingredient in some oil finishes, is derived from the seeds of the flax plant Linum usitatissimum L. Linseed oil is obtained by various methods including pre-expelling, followed by hexane extraction of the resulting press cake. The oil is refined to remove phosphatides and gums, which naturally occur in the oil. Subsequent refining through post-desliming with sulphuric acid and phosphoric acid yields an oil with virtually no traces of phosphatides or gums. Further post-treatments include lye neutralization and earth bleaching, which yields a very light drying oil.

Lippage - A condition evidenced on writing pen barrels when the barrels are oversize at the component mating surfaces. This creates a small lip that can be felt with your finger. Lippage can be caused by incorrect sizing of the barrels to the bushings, variances in the size of the bushings and the pen components, or by applying too much finish on the barrels.

Live Center - The revolving ball-bearing tailstock center on a lathe. The word "Live," refers to the bearings in the center that allow it to rotate when the wood turns. "Dead" centers have fixed center points with no bearings and do not rotate when the wood turns.

Lustre - Synonymous with Gloss. The amount of gloss on a cured film finish. Common descriptions may include: Flat, Satin, Semi-Gloss, or High Gloss, or Low Lustre, Medium Lustre, High Lustre etc.

Woodturning Glossary - Quick Jump Alphabet Selector

Woodturning Glossary M through O

M

Macrocrystalline Wax - Macrocrystalline Wax (Paraffin Wax) is a petroleum wax made from deoiled slack wax, which is derived by dewaxing base distillate lube oil streams of predominantly straight chain alkanes. Paraffin wax is brittle and has a low melting point between 46 and 71 degrees Centigrade. Paraffin waxes impart high resistance to moisture. Due to their low cost, paraffins are frequently added to other wax blends.

Make Coat - The primary coating that anchors abrasive grains onto the backing material. The backing material used (paper, cloth, film etc.) acts as a foundation for the make coat.

Malleability - The ability of a metal to be rolled, pressed or hammered into various shapes without fracture or rupture.

Mandrel - (1) A shaft that is used on various types of tools like Velcro faced foam sanding mandrels, flutter wheels and sanding stars that allows the tool to be used in a drill, or drill press. (2) A specifically sized rod or shaft that is used to hold projects on the lathe for turning, such as a pen mandrel. (3) A small metal disk that is mounted in a Jacob's chuck for turning small diameter inlays for book markers and key chains.

Methanol - Methanol (Also known as Methyl Alcohol) is a clear, colourless highly toxic liquid that has a characteristic, pungent alcoholic odour. It is hydroscopic and miscible in all proportions with water and with most organic solvents. It is less soluble in fats and oils and only partially miscible in aliphatic hydrocarbons. It is insoluble in oil-modified alkyd resins and polymers. Methanol is typically used as a solvent for shellac, cellulose nitrate, colophony and urea resins. It is also used to denature alcohol.

Methanol

Methyl Ethyl Ketone - Methyl Ethyl Ketone (Also known as MEK, 2-butanone, Ethyl Methyl or Methyl Acetone) is a high-strength, clear, colourless specialty Ketone solvent has characteristics similar to Acetone, but with a slower evaporation rate. MEK can be substituted for Acetone to thin epoxy or fibreglass resins. Methyl Ethyl Ketone is used to thin certain nitrocellulose lacquers, ethyl cellulose, acrylic and vinyl acetate-vinyl chloride copolymers. Natural and synthetic waxes are insoluble.

MEK

Micromesh Abrasives - Specialized wet and dry fabric backed, latex faced abrasives available in nine grits from 1500 - 12,000. Frequently used by woodturners for wet sanding alternative materials like plastic to a glass finish, or to polish cured film finishes to a high gloss lustre.

Micromesh wet and dry abrasives

Microcrystalline waxes are obtained from the residual fraction of crude oil distillation (Petrolatum) or from crude oil tank bottoms. Hard grade microcrystalline wax (from crude oil tank bottoms) has a penetration of less than 11 dmm at 25 degrees Centigrade and a melting point of approximately 60 to 93 degrees Centigrade. Plastic grades of microcrystalline wax (from Petrolatums) have penetrations greater than 11 dmm at 25 degrees Centigrade.

Micron – One millionth of a meter, or one twenty-fifth of a thousandth of an inch. This term is used to describe the average abrasive particle size of very fine microgrits and abrasive powders.

Micron Graded Abrasives – A more precise grading system than the traditional "grit" grading process that utilizes stringent controls for producing abrasives with a more consistent and superior scratch patterns. This grading system is typically used with diamond and micro finishing abrasives.

Mineral Spirits - Mineral Spirits (Also known as Stoddard Solvent, Paint Thinner, Varsol or Solvasol) are clear, colourless liquids used to thin oil base paints, stains, varnishes and polyurethane’s to improve levelling, reduce application viscosities and increase penetration. Contains Stoddard Solvent.

Mineral Spirits

Miscible - Capable of blending or mixing uniformly.

Modified Set - A type of setting for bandsaw teeth where the repeating pattern of the tooth set alternates i.e. - right, left, right, left, straight, right, left, right, left, straight...

Mohs Scale of Hardness - In the early 1800's, Friedrick Mohs introduced an arbitrary (non-linear) scale to measure mineral hardness. He selected ten minerals for the scale including Talc which is very soft (given a value of 1), to diamond the hardest material known (given a value of 10). Any mineral listed on the scale can scratch any other mineral listed on the scale with a lower number than itself.

Montan Wax - Crude Montan Wax is a naturally occurring vegetable wax extracted by solvents from lignite coal deposits and peat. Refined Montan Wax has undergone additional processing to remove any resins and asphalt. This hard vegetable wax has a melting point of 79 to 90 degrees Centigrade. The colour ranges from dark brown to light yellow. Montan wax imparts a high gloss and increases water repellence and scuff resistance.

Morse Taper - A specially shaped tapered hole in the headstock spindle, or the tailstock ram that allows the use of accessories like drive spurs, ball bearing centers and Jacob's chucks. Morse taper accessories are held in the taper by contact friction of the two mating surfaces.

To remove a Morse taper accessory, a knockout rod is inserted in the opposite end of the hollow headstock spindle and smacked a few times until the accessory is released. To remove the Morse taper in the tailstock, the tailstock ram is retracted until the ram self-ejects the taper accessory. Some lathes do not have this feature and require a knockout rod to eject the taper accessory.

Morse Taper Reducer - A Morse taper reduction adaptor that allows the use of smaller Morse tapers inside larger Morse tapers. For example, if your tail stock ram uses a #3 Morse taper fitting and you want to use a #2 Morse taper fitting inside your ram, you could use a Morse taper reducer to reduce the #3 taper down to a #2 taper size.

Mottling Embellishment - A specialised finishing technique that applies colour to an object by dabbing, or pouncing the colour onto the surface. Rags or foam sponges are typically used creating a blotched appearance on the object.

Multi-groove Belt - Most newer lathes utilize drive belts that feature numerous tiny "V's" in the contact face of the belt. This design allows for more contact area on the pulley and better power transmission of the power from the motor to the lathe spindle.

N

Natural Edge - (1) Any turned form that incorporates some, or all of the natural outside shape of the tree. Bowls, platters and hollow forms are popular natural edge projects. Natural edge pieces may incorporate the outside bark edge of the tree, or the bark may have been removed leaving the natural outside curve of the trunk or limb. (2) Any turned form that incorporates the natural outside of the blank. For example, Antler buttons.

Classic example of a natural edge Mesquite bowl

Non-Woven Abrasive - Non-woven abrasive pads are constructed of flexible non-metallic materials and do not compromise the surface with metallic fragments that may eventually rust, or discolour pale timbers. The primary abrasives used in non-woven abrasive pads from most aggressive to least abrasive are: Aluminum Oxide (brown, tan, maroon and blue coloured pads), Silicon Carbide (black or grey coloured pads), Alumino-Silicate (green coloured pads) and Talc (white coloured pads).

Non-woven abrasives

O

Odorless Mineral Spirits - Odourless Mineral Spirits is a specially refined, low odour version of traditional mineral spirits. Contains Stoddard Solvent. Odourless Mineral Spirits are used to thin oil base paints, enamels, stains, varnishes and polyurethane’s to improve levelling, reduce application viscosities and increase penetration. Odourless Mineral Spirits is an excellent solvent for oil and wax.

Mineral Spirits

One-Off - A term that relates to woodturnings that are a single unique piece of art, as opposed to making multiple copies of the same item.

Open Coat Abrasive - Open coat abrasives have abrasive grains covering approximately 40% - 70% of the backing surface. This system offers a faster cut and increased flexibility when compared to closed coat abrasive systems. In addition, the open coating offers more resistance to loading on the surface of the abrasive.

Open Time - The length of time before an adhesive sets up, or begins curing. Also known as the Working Time.

Orange Peel - Orange peel is a pebbled like film surface on lacquer or enamel finishes that resembles an orange skin. Orange peel can be caused by the lacquer drying too rapidly when sprayed, or by a failure or combination of failures to achieve the desired leveling effects.

Ouricury Wax - Ouricury Wax is obtained from the fronds of the Syagros coronata, the Brazilian Feather Palm. It is very similar to Carnauba wax in gloss and hardness, but darker in colour. However, the wax is significantly more difficult to extract than Carnauba and requires mechanical scraping of the fronds to release the wax. Ouricury wax has a melting point of 82.5 degrees Centigrade and is sometimes used as a replacement for Carnauba, when a darker coloured wax is desired.

Outboard Turning - Turning projects using the spindle on the left hand side of the headstock. Many lathes offer a threaded spindle on both the inbound and outbound side of the lathe. This allows turning on either side of the lathe. Outboard turning may require reverse threaded accessories and supplemental free standing tool rests, depending on the design of the lathe. Also known as Rear Face Turning.

Oven Dry Timber - Timber that has been dried to a constant weight in an oven at 100 - 105 degrees Centigrade.

Woodturning Glossary - Quick Jump Alphabet Selector

Woodturning Glossary P through R

P

Paper Backing – Lightweight paper backings offer several advantages over other backing materials including lower cost and extreme flexibility. A (lightest), C and D weights are used in paper backed abrasive sheets, rolls and discs. Heavier weight papers used for belt, disk and rolls feature E and F (heaviest) weight papers. B weight papers are a good choice for many woodturning needs.

PAPR - Acronym for "Personal Air Purifying Respirator." PAPR's are typically powered respirators that run on rechargeable batteries with high quality dust filters. Some units also feature cartridges that are capable of filtering out certain harmful fumes. The fan motors may be belt mounted, or integrated into the headset. Some models also feature integrated helmet mounted hearing protectors.

Parting Tool - A woodturning tool designed to part off waste areas on spindles, or to size a part of the spindle to a specific diameter. Parting tools are also used to create small flat areas when turning decorative elements on a project. There are numerous types of parting tools including super thin (1/16" thick), diamond section and standard parting tools.

Part Seasoned - This is a marketing term used by some timber suppliers to describe wood that is not fully seasoned. In practical terms, the wood is fully seasoned or it's green. If you purchase wood that is partially seasoned, treat it like green wood until it has fully seasoned (see EMC).

Paste Wax - A combination of wax and a solvent made into a creamy consistency for easy application. Paste waxes may also include essential oils, drying oils, pigments, dyes or other ingredients.

Minwax paste wax

Peel Strength - The ability of an adhesive to resist being stripped from a bonded joint at a specific angle or rate.

Pen Mandrel - A smooth metal rod that is used to turn writing pens between centers on a lathe. Pen mandrels are usually mounted in a Morse taper adapter, but may also be used in collet chucks. Pen mandrels are available in various styles including single, double and adjustable.

#2MT double pen mandrel

Pen Mill - Also known as a barrel trimmer, a pen mill features a machined cutter head assembly that is mounted to a specifically sized pilot shaft. The mill is used to square the ends of pen blanks 90 degrees to the drilled axis of the blank. The pilot shafts are machined to fit inside the pen tube and guide the cutter head assembly during milling.

Pen mill with interchangeable barrels

Phenol Resorcinol Formaldehyde – Resorcinol is a thermosetting polymer produced by a condensation polymerization between formaldehyde (from the oxidation of hydrocarbons in the presence of a catalyst), phenol (from the oxidation of cumene) and resorcinol (from sulfonating benzene with fuming sulfuric acid and fusing the resulting benzenedisulfonic acid with caustic soda). Two-part resorcinol adhesives (liquid resin, powered catalyst) have a long and successful track record for superior bonding in load bearing timber structures, plywood laminating and for building wooden aircraft and boats. In addition, structural bonds can be achieved on many plastics, leather, natural and synthetic rubbers, primed metals, textiles and fiberboards.

Pin Chuck - A woodturning specialty chuck that is manufactured from a solid cylinder of steel, with a machined flat area near the end. A small steel pin is placed in this flat area before mounting a properly drilled blank onto the chuck. When the blank is mounted on the chuck and turned 1/4 turn, the small pin on the chuck is wedged against one side of the machined flat and holds the blank for turning. Pin chucks come in various sizes and are popular with some turners for mounting regular and natural edge bowl blanks, bottle stoppers and similar projects where the drilled mounting hole will not interfere with the final design of the project.

Pink Aluminum Oxide - (2150 Knoop Scale) Aluminum Oxide that has been alloyed with a small amount of Chromium is known as Pink Aluminum Oxide (PAO). PAO grinding wheels offer very good form holding ability and durability and often contain a small amount of Titanium Oxide to increase overall toughness. Average crystal size is medium, with sharp or blocky shaped grains.

Pitch Pocket - A parallel opening in the annual growth rings of a tree that contains pitch.

P-Grade - An abrasive classification for FEPA (Federation of European Producers of Abrasives) graded abrasive products. There are two main FEPA classifications (FEPA F - Bonded) (FEPA P - Coated).

Plasticizer - Chemicals that are added to some adhesives to soften them to prevent the adhesive from becoming too brittle when cured.

Plexitone Finish - An acrylic based wood finish made from scrap Plexiglass that has been dissolved in Acetone. Plexiglass is the common name for a type of acrylic plastic known as Polymethyl Methacrylate. In addition to being used as a wood finish (it is becoming a popular pen finish), Plexitone can also be used as a homemade stabilizer for soft wood, when thinned to the proper application viscosity.

Plexitone finish master solution

Polishing Paper - Another type of non-woven abrasive that utilizes Silicon Carbide and Aluminum Oxide abrasives in roll, sheet and disk forms. Sizes range from 1 to 30 microns.

3M polishing papers

Polyvinyl Acetate (Aliphatic Resins) – One-part PVA adhesives typically contain polyvinyl acetate, stabilizers, plasticizers and water. Polyvinyl acetate emulsion is manufactured from vinyl acetate monomer. Polyvinyl acetate is used in white glues and yellow carpenters glues, which are commonly known as aliphatic resins. PVA's cure by the evaporation of water, accompanied by the coalescence of the particles. PVA's are widely used for gluing joints in woodworking and woodturning, for bookbinding, lamination, in paper packaging and for sealing Stryofoam materials.

Polyester Abrasive Backing – Man-made cloth designed for applications requiring extreme strength. Polyester cloth backing is stronger and more stable than natural cotton. Rayon and Nylon are also used, as well as blended cloths.

"X" and "Y" weight Polyester cloth – Offers high strength and low stretch characteristics, used for extreme applications. Some X and Y weight cloths feature Poly-Cotton blends.

"YY" and "H" – Strongest cloth backing material used with extreme durability. Typically used for heavy stock removal using course abrasives.

Polyethylene Wax - Polyethylene Wax is a synthetic wax made from selective high, or low-pressure catalytic polymerisation of ethylene feedstocks, which produces waxes with various melt points, hardness and densities. (Ethylene is produced from natural gas, or by cracking petroleum naphtha). High-density polyethylene waxes melt between 85 and 141 degrees Centigrade.

Low-density polyethylene waxes melt between 30 and 141 degrees Centigrade. Polyethylene wax penetration test results vary depending on the type of wax, between 7 and 12 dmm at 25 degrees Centigrade. Polyethylene waxes increase abrasion resistance and help to provide a non-sticky wax surface.

Polymerized Oils - Polymerized oils have been heated in an inert (oxygen-free) atmosphere enough to cause thermal polymerization to occur, but not enough to cause gelation. The resultant oil can be very viscous and is best applied in very thin layers. Two types of commonly available polymerized oil finishes are linseed and tung. These specially processed oils provide faster drying and harder cured films with a more durable glossy luster. Polymerized oil finishes are more expensive than standard oil finishes. In a production environment, polymerized oil finishes allow a significantly faster build, thus saving precious time and labor.

Polyurethane Adhesives – One-part adhesives consist of isocyanate containing pre-polymers, dissolved in a solvent carrier. Reaction with moisture occurs as the solvent evaporates. Unless the curing takes place inside of pressure devices, bubbles may form during curing. One-part polyurethanes are used extensively in woodworking and in woodturning for bonding wood, wood to metal and are also used for gluing metals, ceramics, stone, glass and most plastics.

Two-part polyurethanes contain a polyol resin and an isocyanate hardener that are mixed by the user prior to application. Pot life varies from a few minutes to a few hours. Two-part polyurethanes are used for larger surface adhesion bonds in automotive, marine and container construction. Polyurethanes adhesives are also available in the form of reactive hot-melts. After application, these polyurethanes crosslink with moisture to form a heat, moisture and impact resistant adhesive.

Post-Cure - Adhesive post cure occurs when additional curing of the adhesive occurs in the assembly, after pressing of the assembly has been completed.

Pot Life - The amount of time that an adhesive remains usable after any accelerators, or catalysts have been added. Exposure to any ambient curing conditions (temperature, humidity etc.) can also influence the useful pot life. Also known as the "Pot Time."

Powdered Glass – (~ 5.0 Mohs) Although still available in abrasive sheet form, powdered glass is rarely used today except for hand finishing, or for cleaning ceramics. Glass papers are pale yellow in colour.

Power Sanding - Using various power tools such as electric, or pneumatic drills to sand a project, in combination with foam sanding mandrels and hook and loop backed, or sticky backed abrasives. Power sanding is significantly faster than hand sanding and is the preferred way to sand many faceplate projects like bowls and platters.

Using a pneumatic drill to power sand a Mesquite bowl

Pre-Cure - Adhesive pre-cure occurs when an adhesive sets in an assembly, before the correct amount of bonding pressure has been applied to the assembly.

Pressure Fed Spray Gun - A spray gun that uses a separate pressurized cup or tank (sometimes called a remote tank), to move the finishing material through the fluid tip and into the cap for atomization. Pressure fed guns are used in production spraying applications, or with finishes that are too viscous to use a siphon gun.

Pressure Range - In compressors, the pressure range is the difference between the minimum (known as the cut-in) and maximum pressures (known as the cut-out) of an air compressor.

Pressure Sensitive Adhesive Backed – (Also known as Sticky Backed, or PSA) is a supplemental adhesive coating applied to some paper backed abrasives. PSA abrasives are used with foam or rubber faced sanding mandrels and allow quick changes of grits during the sanding sequence. PSA backed abrasives are not as popular as they once were due to the availability of hook and loop backed abrasives.

Production Work - A very generalized term that relates to multiple copies of similar woodturnings (as opposed to one-off pieces), made by professional woodturners who specialize in one or more different types of work. For example, a production bowl turner may make 100 salad bowls to fill a large order from a buyer, or a pen maker may make 100 pens to fill an order. Also known as Bread and Butter Work.

Profile Scrapers - Scrapers ground with specific shapes or profiles, that are used for various tasks including undercutting bowl rims, cutting specific shapes in the wood surface, or for hollowing boxes.

Kel McNaughton curved profile scrapers

Pull Cut - A pull cut with an Irish ground bowl gouge is where the mouth of the gouge (rounded cutting tip) trails the cutting surface of the tool, in this case, the long swept back wings. Using this example, the sharpened edge of the wings actually cut the wood; the mouth of the tool does no cutting. Pull cuts with Irish ground bowl gouges are made with the side wing bevel rubbing during the cut.

Pull cut on the bottom of a green Mesquite bowl blank

Pure Form - A loosely defined term that relates to turnings where the turned form is intentionally blacked out with paint or dyes, totally obscuring the grain in the timber. What's left is the pure form or shape of the piece, without any visual distractions. While pieces like this may be completed forms, exercises with pure form are typically done on sample turnings, when the turner is trying to determine a visually acceptable shape for a particular project. When the grain is blacked out in a turning, the viewer can concentrate on the curves, lines and overall shape and proportion of the piece. This is an excellent way to develop new shapes and refine a discerning artistic eye.

Push Cut - A traditional bevel rubbing push cut with an Irish ground bowl gouge is where the mouth of the gouge leads the cut and the wings follow. Using this example, the mouth of the gouge and a small portion of the wing near the mouth do all of the cutting. The bulk of the sharp wing surface does not cut, unless a very heavy cut is taken.

Push cut on the side of a green Mesquite bowl blank

Q

Quarter Sawn - A specialized way to cut lumber that orients the annual growth rings approximately perpendicular to the width of the board. Quarter sawn lumber is more expensive than flat sawn lumber due to the lower yields produced per log. Quarter sawn lumber is prized for it's increased dimensional stability (versus flat sawn) and the unique figure produced in some species when quarter sawn.

Quaternary Colours - Any colour that is made by mixing one primary colour (100% saturation) with any other primary colour that is at 25%, or 75% saturation. Quaternary colors include: Red, Cherry Red, Red-Orange, Orange-Yellow, Yellow-Green, Warm Green, Cool Green, Blue-Green, Blue, Ultramarine Blue, Purple-Mauve, and Red-Violet.

Quick Change Backings – Snap lock and twist lock backings offer a quick and easy way to change abrasives. Typically used on very stiff, resin bonded cloth-backed abrasives.

R

Ram - The quill located inside the tailstock. The ram is adjustable in and out by means of a rotating hand wheel. When turned, this hand wheel forces the ram out and exerts pressure on a project for support during turning. When the hand wheel is reversed the ram is withdrawn, allowing the project to be removed from the between centres mounting.

Radial Bristle Disks - A specialty abrasive product from 3M. Radial plastic abrasive discs have a cubitron mineral abrasive embedded in the plastic. As the wheel wears during use, fresh abrasive is exposed. The disks can be used one at a time on a mandrel, or stacked to cover a wider area. Radial bristle disks have become very popular with woodturners who carve or texture their work, as the abrasive will not destroy fine detail. Available in 9/16", 3/4", 1", 2" and 3" sizes, grits vary by size (80 - 400 grit).

3M's Radial bristle disks are popular for sanding textured surfaces

Random Orbit Sander, or ROS - Small electric or pneumatic sanders that feature a dual action design. As the pad rotates, it moves in an eccentric orbit. This creates a very efficient sanding action. Two primary styles are available, palm sanders and pistol grip sanders. In the woodturning world, ROS are typically used with fine grits for finish sanding medium to large projects.

AirVantage 5" pneumatic RO palm sander

Raw Linseed Oil - Raw linseed oil is linseed oil that has been extracted and packaged without any additional additives. Raw linseed oil takes significantly longer to dry than boiled linseed oil. Raw linseed oil needs several weeks or more to cure, vs. 36-48 hours for boiled linseed oil.

Red Rouge - (~ 6.5 Mohs scale) A rouge made from Ferric Oxide that is used by jewelers to polish soft materials.

Resin Bond Systems - Urea and Phenol Formaldehyde resin bond systems offer higher resistance to heat build-up, compared to glue bond systems and are more durable when used for operations involving heavy stock removal. Phenolic-based resins are used more than Urea based systems, as they offer better performance in high temperature and pressure based operational environments. Acrylates and epoxy-based adhesives may also be used as bonding agents.

Retaining Adhesives - Adhesives that are used to prevent the sliding or twisting of non-threaded parts and fasteners. Similar to a locking adhesive (used on threaded parts), retaining adhesives are only used on non-threaded parts.

Reverse Chucking - Taking a project that has been partially turned and turning it around for completing the opposite side. Bowls are frequently turned in this manner.

Right Angle Drill - A drill with a head that is turned ninety degrees to the drill body. Most right angle drills are pneumatically powered and are used with arbor mounted steel cutters, grinding stones and sanding disks.

Makita right angle drill with sanding mandrel pad installed

Ring Center - Turning centers that feature a small ring around the center point. The ring helps to limit deep penetration of the center point into the wood, as well as splitting of the wood fibers from the tailstock's pressure. Ring centers are found on both live and dead centers and are used with many types of spindle and faceplate projects.

Ring Tool - A type of hollowing tool that looks like a ring on the end of a steel shank. The top edges of the ring are sharpened and are used as the cutting surface. Ring tools are popular with some turners for shallow hollowing projects like boxes, weed pots, paper clip holders and similar projects.

Rockwell Hardness Test - A special test made using a Rockwell Harness Testing Machine that determines the hardness of a metal by measuring the depth of penetration created when a hard test point is pressed against the metal at a known load. Softer metals will register deeper impressions, harder metals will register shallower impressions.

Roughing Gouge - A woodturning tool that is used in spindle turning to remove the corners on square stock and make it round. Roughing gouges are also used for gross profiling work on larger spindles to create sweeping curves and contours. The deep "U" shaped flute is typically ground straight across with a 35, or 45-degree face bevel. Roughing gouges should NOT be used for bowl turning.

Rough Turning - (1) Taking green wood projects like bowls or platters and turning a rough profile of the desired shape, with walls that are thicker than necessary for the finished project. When the wood dries and warps after seasoning, the thicker walls allow the warp to be turned away when the project is remounted for finish turning. Most green wood bowls and platters are rough turned first and then dried by various means. Rough turned projects dry much faster than solid blanks of the same thickness, so many woodturners utilize this two step turning method for their projects to speed up the drying process. (2) Turning square section blanks into rounds.

Ruby Aluminum Oxide - A high chrome fused Aluminum Oxide that contains approximately 97% Aluminum Oxide and 3% Chromium Oxide, with fractional amounts of silicon, iron, sodium, magnesium and calcium. Ruby Aluminum Oxide (RAO) is slightly tougher than Pink Aluminum Oxide.

Woodturning Glossary - Quick Jump Alphabet Selector

Woodturning Glossary S through U

S

Sagging - The running or flowing of an adhesive that has been applied to an adherent surface. Sagging can be caused by applying too much adhesive to the surface, or by using an adhesive with too low a viscosity.

Sap Wood - 
The physiologically active outer portion of wood between the cambium layer and the heartwood. Sapwood is less durable and lighter in color than the heartwood in most species.

Scraper - Specialized woodturning tools that scrape the wood surface instead of cutting it. Although scrapers have a bevel edge, it's never rubbed during use. The bevel acts to provide clearance for the sharpened edge only. Larger scrapers are frequently double beveled to allow use inside of smaller openings. Scrapers need frequent sharpening and are used with and without the burr, depending on the species and the turners preference.

Scrapers come in many different sizes, thicknesses and shapes. Among the more popular shapes are bullnose (full round), radius edge (half round or curved), profiled (special shapes) and straight edge. One of the more popular uses of scrapers is to use them in shear scraping mode, instead of as a traditional scraper. Shear scraping can greatly improve the surface of many timbers.

Scroll Chuck - A very popular woodturning chuck that features four jaws that can be opened/closed by the turning action of the spiral scroll mechanism inside the chuck. As the chuck's "T" handle, or "Tommy" bars (depending on model) are turned, all four jaws move in or out at the same time, which helps to center the work in the chuck jaws.

Vicmarc scroll chucks with several jaw sets

Sealer Coat - 
A very thin finish coat that penetrates into the wood to seal the pores and reduce the subsequent amount of finish required to build the top coat. Sealers include shellac, lacquer and spirit based finishing products. Some sealers include additives to make them easier to sand.

Sealing Adhesive - Adhesives that are used to prevent the migration of a liquid or gas between two mating surfaces.

Seasoning - Any process used to dry green timber until it reaches an equilibrium moisture content with the ambient air in its intended storage environment. Woodturners employ numerous methods to dry and season wood including kiln drying (dried with some type of artificial heat in a special oven), air drying (dried without artificial heat in the open air), boiling and bagging in paper bags, microwaving, flame curing, vacuum drying, freeze drying, convection drying and various combinations of the above to name a few.

Segmented Turning - Any turning that incorporates numerous small sections of wood in its design. Larger segmented turnings can include several thousand pieces of wood, all precisely cut and assembled to form special designs or pictures. Segmented turnings include turnings where the entire turning made from segments, as well as those where only a small portion of the turning is segmented like the rim, or foot. With the latter example, the balance of the turning is typically made from a single piece of wood.

Setup Time - The setup time of an adhesive begins when the joint is assembled and is the time necessary for clamping, or the time necessary for pressure to be applied to the joint as the adhesive cures. Any stress applied to the joint during the setup time will reduce the ultimate strength of the joint. The setup time is also known as the Clamp Time, or Pressure Time."

Shear Forces - Forces acting at the same level/parallel to the adhesive layer, producing even stress in the bond surface. Shear forces are commonly referred to as Tensile Shear Strength, since the force is characterized by tensile effects.

Shear Strength - The ability of metal to resist being fractured by opposing forces that do not act in a straight line.

Shear Scraping - A special technique that orients the cutting edge of a scraper at 45 – 50 degrees to the vertical during use. This orientation gives a much cleaner finish off the tool than using a scraper in the traditional manner. When used properly, shear scrapers can produce a surface smooth enough to begin sanding as high as 320-grit. Dedicated shear scrapers like the Kelton (Kel McNaughton) Shear Scraper are made with the proper shear angles ground into the shaft of the tool.

Shelf Life - The useable time an adhesive or finish may be stored without compromise. The actual shelf life is dependent on many factors, including the date of manufacture, the ambient temperature and humidity in the storage area and the quality of the storage container and it's seal against oxygen/moisture.

Shellac - 
Shellac is a resinous exudation secreted from the Coccus lacca, commonly known as the Lac beetle after feeding. Lac beetles are a type of scale insect that is found in India and parts of Asia. After the resin is collected, it is cleaned, dried and formed into thin sheets known as Shellac. The grade and color of the Shellac is determined by several factors including the time the resin was collected, the source of the Lac and the amount of any post collection refining.

Shelling - A term used in the coated abrasives industry to describe an abrasive where the mineral surface has been stripped from the backing.

Silicon Carbide – (~ 9.25 Mohs scale, 2480 Knoop Scale) A black coloured synthetic mineral introduced in 1891 with a hexagonal crystal structure and blocky, sharp edged grains. It is manufactured by the reaction of silica sand (60%) and coke (40%) in an Acheson furnace at temperatures near 2400 degrees Centigrade. Acheson furnaces work by resistance heating, unlike carbon arc heating in fusion furnaces. Silicon Carbide abrasives exhibit very good friable grain structure that break along crystal cleavages to expose new sharp cutting surfaces.

Silicone - Various polymeric materials that contain the Si-O chemical group in their structure. Examples include elastomeric adhesives and sealants.

Sintered Abrasives - Alumina - Sintered Alumina features extremely tough rod shaped grains, with a high body strength and a fine crystal size. Sintered Alumina is used to make grinding wheels for automatic grinders used to condition metal.

Size Coat - The second coating applied to an abrasive product. Once the make coat has cured, the size coat is applied. The size coat functions to securely bond the abrasive grains onto the backing material.

Skew Chisel - One of the most feared and loved of all woodturning tools, skew chisels are used primarily in spindle turning for turning beads, "V" cuts, and for making peeling cuts, planning cuts and tapers. Skews require good tool control and ample practice to master. When properly sharpened and honed, skews can leave a finish on the surface of the wood that needs little, if any sanding.

Skews are available in three basic styles, straight shaft (90 degree corners on all sides), round shaft (full round shaft with skew end) and oval section (shaft is relieved on two sides, making the shaft oval in cross section). Another type of skew is available from some manufacturers features rounded over edges on the shaft to prevent damage to tool rests. Skews are typically ground with a 60-degree edge to the axis and a double beveled end whose angle measures 25 to 45 degrees.

Skip Tooth Blade - A type of bandsaw blade that features evenly spaced teeth with a "O" degree rake angle and shallow gullets that provide good chip removal.

Slipstone - A fine grained oilstone shaped into various profiles that is used to remove burrs and/or hone tool steels. Slipstones are made from various abrasive materials including Silicon Carbide, Ceramic and Diamond. Common shapes include teardrop, cone, round rod, and flat shapes.

End view of some common slipstons

Slow Speed Grinder - A bench mounted electric grinder that features two grinding wheels, one on each end of the drive shaft. Slow speed grinders typically turn at ~ 1,800 RPM. The slower speed of this dry grinder (vs. a high speed grinder) makes it a popular choice for many woodturners for sharpening their woodturning tools. Slow speed grinders come in many different sizes however, 6", 8" and 10" grinders are the most useful for woodturners. Eight inch grinders are the most common size used for sharpening.

Softening Point - The temperature where an adhesive begins to soften, or flow.

Sol-Gel Abrasives - A non-fused ceramic abrasive that is produced by jelling Boehmite (a type of Aluminum Oxide) and adding enhancing modifiers and nucleation agents. Sol-Gel abrasives have a fine grain micro-crystalline structure and are used in precision metal grinding applications.

Soy Oil - Soy oil is obtained from soybeans Glycine maxima (L). Soy oil is considered a semi-drying oil, unless it is modified. It is frequently combined with tung oil in some oil finishes. Soy oil is obtained by cracking and flaking the soybeans, followed by hexane extraction.

Spalted Wood
 - Wood that is in the initial stages of fungal attack and decay. Spalted wood is highly prized by many woodturners for its magnificent color and character. Spalted wood usually contains dark black lines (known as zone lines) that run in irregular patterns throughout the wood. As the fungal activity continues in the timber, areas of the wood are compromised as they loose some of their strength and density. Fungal activity usually ceases when the moisture content of the timber drops below 20%.

Specific Gravity - Gases - The ratio of the specific weight of air, or gas to that of dry air at the same pressure and temperature.

Spigot - 
A turned projection on a woodturning that has been specifically shaped (straight, dovetail etc.) to fit into the jaws of a scroll chuck. 
Spigots are also known as a Boss.

Spindle Adapter - A precision machined spindle adapter that screws onto a lathes spindle to change its thread pitch to another size. For example, if your lathe spindle is 1.25" x 8 Threads Per Inch (TPI) and you have a few faceplates that are 33 x 3.5 mm in size, you could purchase a spindle adapter to change your current 1.25" x 8 spindle to a 33 x 3.5 mm (or another size if desired). Using spindle adapters allows the use of various sized chucks, faceplates and other fixings on a single lathe.

Spindle Gouge - One of the primary tools used for turning fine details and transitional areas on spindle work like beads, coves, and fillets. Spindle gouges are also known as Shallow Fluted Gouges and feature a flute that has a shallow, open arc design. Modern spindle gouges are milled from round bar stock and are available in a variety of high-speed steel based alloys. Some manufacturers offer specially designed spindle gouges made for production work and micro versions for ultra fine detail turning.

Spindle Lock - 
A pin or rod on the headstock that prevents rotation of the spindle so fixings like chucks, screw chucks and faceplates can be mounted, or removed easily.

Spindle Nose - 
The visible end of the spindle with the spindle threads, register, shoulder and the Morse taper.

Spindle Shaft - 
The primary threaded attaching point on a lathe headstock. The spindle shaft is threaded to accept fixings like chucks, faceplates and other threaded accessories and is usually bored to accept Morse taper accessories. The spindle shaft rotates inside bearings located inside the headstock. The number and type of bearings varies by manufacturer. 


Spindle Turning - One of the primary methods of mounting and turning projects on the lathe. Spindle turning involves turning projects between centres, (headstock and tailstock). Most spindle turning orients the grain so that it's parallel to the lathe bedway. 
Examples of spindle turning include pens, chair rails, balusters and finials to name a few.

Split Forces - Forces that act on an adhesive joint where one part of the joint is exposed to high stress and the other part of the joint is unaffected. This results in an uneven stress across the entire bond surface.

Stand Oil - Stand Oils are drying oils with increased viscosity, which are produced by heating the oil in the absence of oxygen. In order to increase the viscosity of the boiled oil, air is sometimes “blown” through the oil at 60°-100° Centigrade. Blown linseed oils are polymerized by oxidation to increase the viscosity and acid number. Blown linseed oils are used in non-penetrating finishes and dry faster than heat bodied linseed oils.

Starved Joint - A glue joint without a sufficient amount of adhesive to produce a satisfactory bond.

Steady - 
Any device, or jig that used to stop vibration of thin spindle work, or thin walled faceplate projects. Spindle steadies and bowl steadies are two examples.

Stoke - Stoke is the Poise divided by the density (or weight per gallon (X) 0.120). 100 Centistokes = 1 Stoke. The Centistoke is the established unit of reference in all viscosity cup measurements. See Viscosity and Centipoise.

Structured Abrasive - Abrasives with a fixed composite pad of vitreous diamond agglomerates in a cross-linked polymer binder. Structured abrasives are available in 3, 6 and 9 micron sizes on a PSA backing. 3M's Trizac abrasive is an example of a structured abrasive.

Suction Feed Spray Gun - A type of spray gun that used a stream of compressed air to create a vacuum at the cap. This vacuum creates a siphoning action that moves the liquid up the pickup tube, into the gun and out the tip where it's atomized by the air cap. Suction fed spray guns are typically used on smaller finishing projects where frequent colour changes may be required, or for touch-ups.

Super Glue - 
A common name for Alkyl 2-Cyanoacrylate adhesives. 2-cyanoacrylate ester monomer bases are all thin, crystal clear liquids with viscosities ranging from 1 - 3 mPa’s (=cP). Because the base monomers are very thin, stabilizers, thickeners and other property-modifying additives (soluble polymers and plasticizers) are used to alter the viscosity, physical characteristics, performance and elastification of the formulations.

CA adhesives are available in numerous viscosities ranging from near water thin wicking grades, to thixotropic (fluids that are gel-like at rest, but fluid when agitated) gels that range from 20,000 to 50,000 mPa’s (=cP). These super thick CA’s are used with large gaps, or when a longer setting time is required for proper application.

Super Size - Some abrasives feature a third coating when manufactured, known as the Super Size. (Also known as the Top Size) This is applied after the size coat has cured and carries lubricants such as Zinc Stearate, which reduces friction and loading of the surface when sanding.

Swing - A mathematical reference to the maximum blank diameter that can be swung (turned) over the lathe bedway. The swing is calculated by measuring the distance from the top of the bedway, to the centre of the spindle shaft. This measurement is then doubled to determine the maximum swing. Thus, a lathe that measures 12" from the top of the bed to the centre of the spindle would have a 24" swing (12" x 2 = 24").

Swivel head - Lathes that feature a headstock that can be pivoted around it's vertical axis, allowing large projects that will not fit over the lathes bedway to be turned.

T

Tack - An adhesive property that creates measurable bonding strength immediately after the adhesive and the adherent are in contact.

Tackifier - Chemicals that are added to some adhesives to make them stickier. Tackifiers help to hold the substrates together, whilst the adhesive is curing.

Tailstock - A moveable locking/clamping assembly on a lathe that slides up and down the bedway. The tailstock houses the tailstock quill or ram, which is adjustable in and out by means of a hand wheel that exerts pressure on a project for support during turning. The tailstock assembly is usually made from the same material as the main body of the lathe, typically cast iron or steel.

Tailstock Live Center - 
A ball bearing center that is mounted in the tailstock quill or ram, that is used to support the end of a project blank when turning. The ball bearings in the live center allow the blank to spin with the spindle shaft as it rotates. 


Tang
 - The tapered portion of a woodturning tool which is made to fit inside a tool handle.

Tall Oil - Tall oil is a by-product of the sulphate process of producing cellulose from conifers. Pine trees produce the highest quality tall oils. Tall oil is not technically an oil, but a mixture of unsaturated fatty acids, rosin acids and unsaponifiable components. Tall oil is an important component in the manufacture of Alkyd resins.

T.E.F.C. - Acronym for an electrical motor that is manufactured as a "Totally Enclosed - Fan Cooled" motor. TEFC motors are used frequently in machinery that is subject to dusty environments.

Tensile Forces - Tensile forces act vertically to the adhesive layer, i.e. the entire bond surface is evenly stressed.

Tensile Strength – (1) The maximum amount of stress a material can withstand when stretched without tearing. (2) The ability of a metal to resist being pulled apart by opposing forces acting in a straight line, expressed as the number of pounds of force that is required for a bar measuring one inch wide and one inch thick to be pulled apart.

Thixotrophy - A property of some adhesive compositions to thin upon isothermal agitation and to thicken when the agitation is stopped, or the adhesive is allowed to rest.

Thermosetting - Polymeric materials that harden when exposed to high temperatures and pressures. Once hardened, these materials cannot be softened, or melted again with further heating.

Toluene - Toluene (Also known as Methylbenzene, Toluol, Methacide, Methylbenzol or Phenylmethane) is a colourless, flammable aromatic hydrocarbon solvent of low viscosity, similar in strength to Turpentine, but with a faster evaporation rate. Toluene is similar to benzene and has a benzene-like odour. The catalytic reforming of refinery streams typically produces toluene. The resulting crude reformate is extracted with sulfolane, or tetrathylene glycol and a cosolvent to yield a mixture of benzene, toluene, xylenes and C9 aromatics. These are then separated by fractionation. Toluene is used to thin specialty paints, resins, dyes, coatings and some waxes. It is often used in cold weather to speed the drying of oil-based coatings.

Toluene

Tooth Angle - The angle of the tooth face on a bandsaw blade in respect to an imaginary line that is perpendicular to the blade.

Tooth Face - The surface of the tooth on a bandsaw blade that is facing the direction of travel.

Toolrest - A removable and adjustable tool rest support for woodturning tools that is held in the tool rest holder/banjo. Tool rests are normally shaped like a "T", but also come in other shapes. Larger lathes typically include a 6" and 12" long straight tool rest as standard accessories. Specialty tool rests are available in curved, box, "S" curved, angled, extra long and skewed configurations to meet specific woodturning needs. Also known as a Handrest.

Toughness (Metal) - The ability of a metal to resist fracture and failure after damage has started. Toughness decreases as hardness increases.

T.P.I. - Teeth Per Inch The number of teeth on a bandsaw blade when measured across one inch, from gullet to gullet.

Tung Oil - Tung oil is obtained from the seed kernels of the Tung tree, Aleuritis fordii, Chinese tung oil or Aleuritis cordata, syn. vernica and verrucosa, Japanese tung oil. The principal source of raw tung oil is China and South America. The nuts of Aleuritis montana, Aleuritis trisperma (kekunaoil) and A. moluccana or A. triloba (lumbang oil) also produce oils with properties that are similar to Chinese tung oil.

U

Ultraviolet Adhesive - An adhesive that's made to cure when exposed to specific levels of ultraviolet light. Ultraviolet adhesives are used frequently in industrial manufacturing applications, as well as some advanced home/hobbyist applications.

Unblended Oils - Unblended or pure oils typically include oils extracted from plants, nuts or petroleum. Examples of pure or unblended oils include; raw linseed oil, tung oil, kukui nut oil, macadamia nut oil and walnut oil. The labeling on the oil finish should include the words “pure” or “100 percent,” or the oil may be blended with other ingredients. Pure Tung oil is sometimes referred to as “China Wood Oil”.

Urea-Formaldehyde Adhesive(Plastic Resin Glue) - Urea-formaldehyde adhesives are thermosetting polymers produced by a condensation polymerization reaction between urea (derived from a reaction between liquid ammonia and liquid carbon dioxide that forms ammonium carbamate, which decomposes at low pressure into urea and water) and formaldehyde (derived through the oxidation of hydrocarbons like methanol, propane, or butane in the presence of a catalyst).

Widely used to make products like plywood and particleboard with heated hydraulic presses, where dimensional uniformity and surface smoothness are important. Plastic resin glues are also used for building fly fishing rods and water skis, furniture construction, millwork, assembling hollow core doors, in aircraft construction and for adhering decorative laminates to wood.

Woodturning Glossary - Quick Jump Alphabet Selector

Woodturning Glossary V through X

V

Vapour Pressure - Outward pressure of a mass of vapour at a specific temperature. Vapour pressure is an index of a liquids volatility.

Varnish - Standard varnishes include modern varnishes and polyurethanes, which are thinned with petroleum distillates until they reach application viscosities. Some of these varnishes are thin enough to be wiped on, like a typical oil finish. These thinned finishes are in reality a wipe-on or wiping varnish, but they are usually marketed as oil finishes. Thicker varnishes are made to be brushed on, but many of these can be successfully wiped on as well, with hand or high-speed methods.

Varnishes are made by heating drying or semi-drying oils like linseed, tung, soybean or safflower at high temperatures with natural or synthetic resins, until the proper viscosity is achieved. The resultant varnish is then thinned with hydrocarbon solvents to reach application viscosity. Natural resins used may include congo, copal, manila, amber, damar and kauri resins and others. Synthetic resins may include ester gum, phenolic resins, alkyd, polyurethane or coumarone-iodine resins. Today, natural resins are seldom used, being largely replaced with synthetics in most varnishes.

Viscometer - An instrument that is used to measure the viscosity of liquids.

Viscosity - The resistance of a liquid to shear forces/resistance to flow.

VM & P Naphtha - VM & P Naphtha (Also known as Ligroin, Varnish Makers and Painters Naphtha, Benzin, Petroleum Naphtha, Naphtha ASTM, Petroleum Spirits or Petroleum Ether) is a mild strength, fast evaporating aliphatic hydrocarbon solvent similar to Paint Thinner or Mineral Spirits. In some cases, it is superior for thinning oil base paints and varnishes.VM & P Naphtha is used to thin oil base paints and varnishes to improve levelling and reduce application viscosities where its faster drying time would be desirable over standard Mineral Spirits.

Volatile - Substances that evaporate quickly or readily. Volatile compounds in finishes are referred to as VOC's, or volatile organic compounds.

Vulcanized Fiber – A cloth based backing made from cotton that has been treated with chemicals to create a gelatinous surface. The treated fibers are stacked and heat-treated (vulcanized) to produce a stiff backing material. Normally used with resin-based disks that contain course abrasives.

W

Wax - Wax is one of the oldest and most versatile natural substances ever used by man. Wax is a very complex mixture of many different types of compounds. It can be simply defined as a substance that is solid at ambient temperature and when subjected to moderate temperatures, becomes a low viscosity liquid.

Wax Creep - Seepage of paste wax from a sealed tin. Wax creep can be caused by numerous factors including excessive heat during storage, the particular design of the tin and excessive wax residue left under the sealing portion of the lid.

Wax Types - There are many different types of waxes. However, for simplicity they can de subdivided into these relevant groups: Insect (Beeswax and Shellac Wax), Vegetable (Carnauba, Candelilla, Ouricury and Japan), Mineral Waxes (Montan, Ozokerite, Ceresine), Petroleum (Macrocrystalline - Paraffins and Microcrystalline) and Synthetic Waxes (Polyethylene).

Waney Edge - 
A natural edge shape on a sawn board or plank that is created by the exterior shape of a tree.

Wave Edge Abrasive Disks - Specially shaped abrasive disks that feature an undulating, or scalloped outer edge, instead of a circular edge. This wave edge allows the abrasive to conform to the contours on projects better when sanding, as well as allowing some sanding on the lower edge of the foam sanding mandrel.

Wave edge sanding disks are frequently used to sand the interiors of bowls

Wax Emulsion - A white coloured cold wax emulsion product that is used to control the rate of moisture loss in green timber, by forming a durable wax membrane between the exposed end/side grain and the surrounding ambient atmosphere. The goal is not to prevent moisture from moving through the wax coating, but instead to retard the rate of moisture evaporation, thereby reducing drying defects like end grain checking and warping.

Anchorseal is a popular wax emulsion for green wood

Wet Sharpening/Grinding - The process of sharpening woodturning tools at a very low speed (~ 90 RPM), using a water cooled sharpening system like the Tormek T-7. Systems vary, but common features include a 10" wheel that is continually bathed in water during sharpening and a leather honing wheel. Multiple tool jigs are available to sharpen almost any tool. Advantages of wet grinding include: 1.) Minimal metal removed during sharpening, 2.) No danger of overheating your tool, 3.) Ability to resharpen the tool at the exact bevel angle, 4.) Ability to sharpen the tool to 6,000 grit or higher.

Using a Tormek wet sharpening system to sharpen an Irish ground bowl gouge

Wetting - 1.) Coating a substrates surface with an adhesive. 2.) The intimate contact between a liquid and a surface. Proper wetting of mating surfaces is critical to achieving a good adhesive bond. 3.) The ability of an liquid adhesive to flow evenly over the surface of an adherent and to display an inter-facial affinity for the surfaces.

Wet Turning - 
The process of turning green (fresh cut, or wood with high moisture content) or unseasoned wood. Wet turning is also called "Green Turning, or Turning Green" and is popular with woodturners all over the world. Projects may be completed from green to finished form in one step, or roughed and allowed to dry and finished in two steps.

Green wood one step projects will develop a natural warp as they dry and are sometimes referred to as "Natural," or "Organic Forms." With two-step projects, any warp caused during drying is turned away during the finish turning process.

White Aluminum Oxide - A type of Aluminum Oxide that contains 99% pure white, low soda Bayer Process Alumina. White Aluminum Oxide (WAO) is almost totally free of Titanium and contains no silica, or iron. WAO exhibits the best friability of any of the Aluminum Oxide abrasives.

White Spirit - White Spirit (Also known as Turpentine Substitute) is a general name for colourless, low aromatic liquids that are similar to turpentine in their volatility and solubilizing ability with waxes, coatings and resins. Contains Hydrocarbon liquids distilling under 300° Centigrade and Benzene.

Turpentine substitute formulas vary and may include high-boiling naphthas, hydrogenated hydrocarbons, decalin and tetralin. Essential oils are sometimes added to improve the odour. Orange-peel terpenes (primarily d-limonene) are usually included in this general group for classification purposes. White Spirit is generally used as a solvent, or thinner for oil-based coatings and varnishes.

Wood Hardener - Products that are designed to penetrate and harden soft, punky or rotten wood fibers. Wood hardeners may include products based on epoxies, acrylics, cyanoacrylates and various resins.

Minwax Wood Hardener

Work Hardening - A condition evidenced on steel when the steel becomes harder due to repeated cutting, bending or flexing.

Working Life - The amount of time that a resin based adhesive remains workable after mixing (before hardening or gelling) in the mixing container.

X

Xylene - Xylene (Also known as Xylol, Dimethylbenzene, Methyltoluene or Violet3) is a clear, colourless medium strength aromatic hydrocarbon solvent similar to Toluene. Xylene is used as a thinner for specialty paints and coatings. In hot and humid weather, it is frequently added to Lacquer. Xylene is typically extracted from crude oil or coal. The raw materials are subjected to thermal or catalytic treatments where aromatics and xylene containing fractions are obtained.

X - Y Vice - A drill press locking vice that allows movement in both the X and Y axis, via the rotation of two adjustment levers. This type of vice allows you to easily center small turning squares like bottle stoppers and pen blanks for accurate drilling in the center of the blank.

Woodturning Glossary - Quick Jump Alphabet Selector

Woodturning Glossary Y through Z

Y

Yellowing - The development of a yellow colour or cast after aging, or curing.

Yellowing - (Linseed Oil) - The yellowing of linseed oil is thought to be caused when conjugated unsaturated hydroperoxides are converted into conjugated unsaturated ketones. These unsaturated ketones can produce long-chain colored polyenes. Additionally, if 1,4-diketones are formed during the drying, enol tautomers can react with trace amounts of atmospheric ammonia.

This produces a substituted pyrrole, which can be converted into a colored product by oxidation, or by condensation in the presence of formic acid. Colored metal siccatives can also contribute to the discoloration and/or yellowing of linseed oil. To alleviate the yellowing, saturated aliphatic aldehydes may be added to the oil.

Z

Zahn Cup - An efflux viscometer measuring device that consists of a small cup with a hole in the bottom. Zahn cups are used to measure the viscosity of liquids, by dipping the cup into a liquid and noting the time it takes for the cup to empty through the bottom hole. The total time required to empty the cup correlates to a specific viscosity on an accompanying chart.

Zinc Stearate – A dry white-gray coloured non-abrasive lubricant that is added to some coated abrasives to reduce loading of dust and resins on the surface of the abrasive. Abrasives with zinc sterate coatings are typically referred to as Sterated abrasives by woodturners.

Woodturning Glossary - Quick Jump Alphabet Selector

Steven D. Russell is a professional studio woodturner, teacher and writer. He has written numerous articles for international woodturning magazines, which have been published in more than 78 countries around the world. Steve has demonstrated in numerous cities across the United States. His studio, Eurowood Werks, specializes in bowls, platters and hollow forms with unique visual and tactile treatments.

Steve is also a regular featured writer for the Guild of Master Craftsman's "Woodturning" magazine, published in London England. Woodturning magazine is the world's leading magazine for woodturners. Look for his monthly articles covering technical topics, or project based articles in each issue.

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