Multimedia Woodturning Glossary

Welcome to the Woodturning Videos Plus Multimedia Woodturning Glossary. This reference will be updated on a regular basis, so be sure to bookmark this page for future reference. Listings in this reference 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.


This page contains Glossary entries for A - I. To access additional Glossary pages, use these quick links:

J - P

Q - Z

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!


Woodturning Glossary
Quick Jump Alphabet Selector

[A] [B] [C] [D] [E] [F] [G] [H] [I]


Woodturning Glossary A through B


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 Flexing – A special post manufacturing process that some abrasives undergo whereby the abrasive belts are rolled over a specially shaped metal edge at various angles to break the coating on the abrasive and improve its overall flexibility.

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

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

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

Aluminum Oxide – (~ 9.0 Mohs Scale) One of the most popular man-made abrasives, featuring very tough wedge shaped grains that lack a clearly defined crystal structure. Aluminum Oxide was introduced in 1900 and is manufactured using an electric arc fusion process from Bauxite in a Higgins furnace at 2600 degrees Centigrade. Aluminum Oxide abrasives include those made from Brown (the most common type used in coated abrasives), White, Pink and Ruby Aluminum Oxide grains.

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

Annual Rings – Concentric growth rings added yearly to growing trees that are visible on the endgrain portions of cut logs.

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

ASTM - American Society for Testing and Materials – Organization for technical standards.

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

Banjo – The primary lathe fixing that holds the tool rest. The banjo clamps to the lathe bedway. The banjo is fully adjustable up and down the length of the lathe bed, as well as in and out (across the bed). Banjos are also known as Tool Rest Holders.

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

Bond - An adhesive or glue that anchors abrasive grains to the backing material.

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 Rest – A specially designed tool rest that extends into the hollow of a bowl, effectively reducing vibration by limiting the distance the tool overhangs off the end of the tool rest. 


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 turner's 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.


Woodturning Glossary C through D


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

Cambium - A specialised layer of cells located between the inner bark and the sapwood where new growth is created. Each side of the cambium has a specialised function. New sapwood cells are created on the inside of the cambium, new bark is created on the outside of the cambium layer.

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

Carvers Jig - A specialized work holding jig that allows lathe mounted projects to be worked off the lathe spindle. Carvers jigs feature spindle replicators that allow lathe fixings like chucks and faceplates to be mounted, without removing the project from the lathe fixing. This is a significant feature that preserves the original axis of rotation on the project during off-lathe embellishments.

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 Point - (1) The common term for the pointed ends on a drive spur. (2) A tailstock revolving ball bearing center.

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

Ceramic Aluminum Oxide – An exceptionally hard and sharp synthetic abrasive with a very uniform crystalline structure that is formed when Alumina gel is dried and crushed. The name is derived from a manufacturing process that is similar to the manufacture of industrial ceramics.

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

Cloth Backed Abrasive – Cotton cloth backings are available in a variety of weights and configurations. Since cloth backings are significantly stronger in use than paper, they are frequently used as backings on belts, disks and flap type wheels. Waterproofing requires supplemental treatments.

"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.

Cool Batching - Preparing a two-part adhesive, or finish with slightly less catalyst than the manufacturer recommends. This technique is sometimes used based on ambient temperature, humidity or surface conditions to slow the curing of the product to produce a better end result.

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

Cubic Boron Nitride - (~ 9.9 Mohs Scale, 7800 Knoop Scale) Cubic Boron Nitride (CBN) is manufactured under high heat and high pressure conditions and is second only to a diamond in hardness. CBN is thermally stable at temperatures up to 2000 degrees Centigrade. CBN is used for grinding hard ferrous metals and tool steels including nickel, cast iron, and cobalt based alloys.

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.


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

Deluxing Fluids - Deluxing fluids are similar to cutting waxes, but are in a liquid form and usually require power buffing to perfect the film surface.

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 leveling, reduce application viscosity and improve penetration. Shellac thinned with denatured alcohol gives a smooth, high gloss film with improved working consistency.



Denatured Alcohol

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.

Desiccant - A material that is capable of attracting and removing water vapour from the air. Desiccants are frequently used on compressed air supply lines to remove moisture from the air before spraying finishes.

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.


Woodturning Glossary
Quick Jump Alphabet Selector

[A] [B] [C] [D] [E] [F] [G] [H] [I]


Woodturning Glossary E through I


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

Fiddleback - A beautiful and highly sought after figure in wood that appears as wavy, or rippled grain. Also known as curly grain, fiddleback grain produces a chatoyancy that changes as the light is moved around the piece.

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


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 its 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


H

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

Handrest - Another name for the lathe toolrest. See Toolrest.

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.

Hiccupping - 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 hiccupping. To prevent hiccupping, 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 & Loop Backing (H&L) – A quick-change attachment system composed of a backing pad with a fine looped surface and an attachment pad with tiny hooks. This type of backing is very popular with woodturners as it allows very fast grit changes when power sanding. Commonly referred to as Velcro backed.

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

Induction Motor - A type of alternating current electric motor that does not have "brushes". Most lathes are equipped with induction type electric motors. The speed of the motor is proportional to the frequency of the alternating current.

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
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Safety Note: Always follow all manufacturers safety instructions before working with your lathe, or any of the tools or products you may use. If you are unsure about any operation, obtain competent professional instruction before proceeding. Use and wear all necessary safety devices during turning and observe safe woodturning practices to prevent accident or injury.


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 the current and founding President of the Lone Star Woodturners Association, Inc., an AAW member chapter. The LSWA is a 501(c)3 non-profit educational organization dedicated to teaching and demonstrating the art and craft of woodturning.

Steve is also a 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 articles covering technical topics, or project based articles in an upcoming issue.