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Glossary of Woodturning Terms
A,
B, C, D,
E, F, G,
H, I, J,
K, L,
M, N, O,
P, Q, R,
S, T, U,
V, W, X, Y,
Z.
A,
B,
C,
D,
E,
F,
G,
H,
I,
J,
K,
L,
M,
N,
O,
P,
Q,
R,
S,
T,
U,
V,
W,
X,
Y,
Z.
Air-dried
See seasoning
Anisotropic
Not possessing the same properties in all directions (the opposite of
isotropic). Because of its fibrous structure wood is anisotropic.
Bast
The inner bark. The carbohydrates, formed in the leaves by
photosynthesis, flow down through the cells in the bast to feed the
life processes of the tree.
Backsteady
A means of supporting a long thin spindle to help to stop it flexing in
the centre. Also just called a "steady"
Banjo
The part on the lathe which slides along the bed and supports the T
rest.
Bead
A rounded raised portion running around a spindle turning.
Beading tool
A small chisel (often square in section) used to form a bead.
Bed
The horizontal part of the lathe which connects the headstock and
tailstock
Bedan.
Chisel shaped lathe
tool used for spindle turning ina similar way to a skew.
Bevel
The part of the tool which is ground to form the cutting edge.
Birdseye
Numerous small areas on the surface of the wood in which the fibres are
distorted so as to produce elliptical forms somewhat similar to bird's
eyes. Found in maple and sycamore, rare in other species.
Blank
The blank is the form the piece of wood takes when it has been prepared
for turning. Typically this will be a round disc for a bowl or a
similar face turning, or a relatively slender 'square' sectioned piece
for turning between centres.
Bowl gouge
A gouge with a deep flute and a heavy cross-section. Its primary
function is for face turning but it can also be used for spindle
turning. It is most commonly ground with a 40°- 60° bevel angle.
Bruzze
A rare tool (Sometimes known as a bruzz or a buzz) which has a 'V'
section. A turner's bruzze has the bevels ground on the outside,
whereas a carpenter's bruzze is ground on the inside.
Built-up
work
A workpiece which is made by gluing together two or more pieces of
wood.
Burl
The American term for a growth on a tree which in Britain is called a
burr. See also: burr (1)
Burnishing
Polishing by friction. In woodturning this is usually carried out by
holding a handful of shavings against the revolving workpiece. The
shavings should come from the work being burnished.
Burr (1)
A large wart-like growth, with twigs sprouting from it, found on the
trunk of a tree. Internally the wood tissue is very confused and
usually contains numerous dormant bud formations. The wood cut from a
burr usually shows very attractive figure and is very highly prized by
turners.
Burr (2)
A fine upstanding strip of metal left on the edge of a tool after
grinding or the use of a ticketer. (It is sometime called a wire edge.)
This can be honed off but many turners make use of the burr on a
scraper to produce a very fine finishing cut.
Callipers
A measuring tool consisting of two curved arms connected at one end by
a hinged type joint. In their simplest, traditional, form they can be
used for both inside and outside measurements. In their modern form the
hinge is sprung and the arms are connected midway by an adjustable
screw. In this form inside and outside callipers are separate devices.
Cambium layer
A thin layer of specialised cells which lies between the inner bark and
the sapwood. It is here that the growth of the tree takes place. New
sapwood cells are formed on the inner side of the cambium, and new bark
is formed on its outer side.
Centres
The parts in immediate contact with the workpiece when it is held in
the lathe by both ends. Hence the expression 'turning between centres'.
See also: cone centre, dead centre, drive
centre, live centre
and ring centre
Centrifugal
force
The force with which a body revolving around a centre tends to fly away
from that centre. The force which causes pieces to fly off when work is
revolving on a lathe.
Check
See split.
Checkered
work
Usually requires two laminations. Stripes cut then reglued to form
checks. See also laminated work
Chisel
A woodturning tool with either a square or a rectangular cross-section
which is ground with a double bevel. See also skew chisel and square
nose chisel.
Chuck
A device which holds the workpiece on then lathe. A chuck can take many
different forms. See, for example, cup
chuck, precision combination
chuck, screw chuck,
and scroll chuck.
Collets
The movable metal parts in a chuck which grip the tool or the
workpiece.
Cone centre
A live or a dead centre with a cone shaped point in the tailstock used
to support the workpiece. See also centres
Cove
A semicircular hollow running round a spindle turning.
Crotch wood
Wood which lied immediately below the fork of a tree. When this wood is
sawn lengthways (ie parallel to the pith) it can produce exceptionally
beautiful, fan shaped, figure. Because of its beauty crotch figure is
greatly prized.
Cup chuck
A chuck with a deep recess
into which a spigot on the workpiece can be driven.
Cup shake
A split formed by the
separation of the wood fibres around a growth ring.
Dead centre
A cone centre which does not revolve with the work. See also centres
Deep fluted
gouge
See bowl gouge
Dividing
head
See index plate.
Drive centre
This is attached to the drive shaft in the headstock by either a morse
taper or a thread. It both supports the wood and transmits the drive to
it. Usually it has either two prongs or four prongs which are driven
into the workpiece. See also centres
Dovetail
recess
A recess with an undercut edge cut in a workpiece to accept the jaws of
a chuck.
End check
A split on the end of a
board.
End grain
turning
Turning in the end of a workpiece, which has the grain running parallel
with the axis of the lathe, the other end of which is held by a screw,
or other type of chuck.
Exotic
timber
Imported timber of a type not indigenous to Britain.
Faceplate
Circular plate held on the headstock spindle to which the workpiece is
attached by screws.
Face turning
Turning workpiece held on a faceplate, or a chuck when the grain of the
wood runs at right angles to the axis of the lathe.
False
Faceplate A piece of waste wood glued to the work to hold the
work on a faceplate. This avoids having screw holes in the work itself.
Fiddleback
Figure which is produced by wavy grain when quarter sawn. It appears as
a rippled effect on the surface, eg ripple maple/sycamore. The term has
come into use because such wood with this figure has traditionally been
used for the backs of violins.
Figure
The pattern on the surface of the wood caused by the combination of
such features as grain, growth rings, rays, tissue structure, colour,
knots, burr, and, sometimes, defects.
Filler
Used to fill the grain when a smooth finish is required. It is applied
after the primary sanding operation. The work may be sanded again after
the application of the filler and before the final polishing .
Filling
The application of filler.
Fingernail
The shape of the ground end of a spindle gouge.
Finishing
The final treatment of the work after the tool-work has been complete,
eg sanding, filling and polishing.
Flitch
A section of timber cut lengthwise from the trunk of the tree,
Fluted
parting tool
A tool with a wedge shaped section which has a flute on the wider of
the two edges.
Forstner bit
Forstner bits are similar to sawtooth bits but they are guided by their
rims and do not have a centre point. As a consequence they cut flat
bottomed holes which can overlap each other or the edge of a board.
they do not cut as well as a sawtooth bit in end grain.
Four jaw
chuck
A self-centreing chuck similar to the engineering type but with four
jaws instead of three. These chucks are often known as scroll chucks
because of the internal spiral grooves which move the jaws.
Gouge
A cutting tool with a 'U' shaped cross-section used with the bevel
rubbing. There are three main types: the roughing gouge, the spindle
gouge and the bowl gouge. For the latter two of these some turners
prefer the terms shallow fluted gouge and deep fluted gouge
respectively. The reason for this is that bowl gouges can be used for
spindle turning and spindle gouges can be used on face work.
Grain
The alignment of the cells relative to the long axis of the tree,
straight, diagonal, interlocked and wavy grain.
Growth rings
Each of these rings is the result of one year's growth. The rings are
often easy to distinguish because the wood produced in the later part
of the year is darker than that produced when the sap rising.
Headstock
The assembly fixed on the left-hand end of the bed of the lathe which
provides the drive for the workpiece.
Heart shake
A split running radially away
from the pith.
Heartwood
The fully developed wood which surrounds the pith. It is often darker
in colour and harder than the sapwood which surrounds it. The cells in
the heartwood are dead and have ceased to transport sap.
High speed
steel (H.S.S.)
High speed steel; this is about 6 times harder than carbon steel. HSS
tools should be ground on a 'white' (aluminium oxide grinding wheel).
Hone
To sharpen a tool by hand on a stone.
Honeycomb
An interior split, or group of
splits, in a block of wood - usually only found in larger sections.
Probably due to over-quick drying. Unfortunately, often not discovered
until work is in progress.
Hook gate
See Sizing tool
HSS
See high speed steel
Inboard turning
Face turning which is carried out over the bed of the lathe, ie on the
right-hand of the headstock.
Index plate
A plate used to lock the drive-shaft into a series of pre-set regular
positions. The plate is sometimes built into the lathe and sometimes is
a separate attachment used for specific jobs.
Jacob's chuck
Originally a proprietary name for a type of drill chuck which can also
be held in the headstock or tailstock of a lathe. It can be used to
hold a small workpiece instead of a drill.
Kiln-dried
See seasoning
Lace bobbin drive
A drive centre with a recess in the outer end to accept a lace bobbin
blank.
Laminated work
A workpiece constructed from glued-up blocks. It should be allowed to
dry thoroughly after gluing and then turned with sharp tools at a slow
speed because centrifugal force can cause the pieces to separate.
Live centre
A centre in the tailstock which revolves with the work. See also centres
Mandrel
A means of holding a workpiece (or workpieces) by use of a rod of wood
or metal running through a central hole, as for toy wheels and napkin
rings.
M.C.
See moisture content.
MDF
Medium density fibre board - a man made material used as an alternative
to wood.
Medullary rays
Bundles of cells which run radially between the pith to the cambium
layer. They are much more easily seen in some woods, such as oak, than
others. The tree uses these cells for the storage of nutrients.
Moisture
content
The weight of the water in a sample of wood expressed as a percentage
of the weight of that sample when it is completely dry. Often
abbreviated to the M.C. of wood.
Moisture
meter
An electrical instrument for determining the moisture content (MC) of
wood. There are two types of meter. One type measures the electrical
resistance of the wood, the other measures the dielectric property of
the wood.
Morse taper
A standard taper on a drill chuck or lathe drive centre which enables
the device to be removed from. or attached to, the relevant machine
quickly and easily. Abbreviated to M.T.
M.T.
See morse taper.
Natural edge
The lip of a bowl or a goblet which shows the outside of the tree -
often with the bark in place.
Ogee
An elongated 'S' shaped curve.
Outboard
turning
Face turning which is carried out on an extension of the drive-shaft on
the left-hand side of the headstock, ie the opposite side to the bed.
Relative to the turner the workpiece will revolve in the opposite
direction as compared with turning over the bed; as a consequence the
drive spindle and attachments, such as a faceplate, require reverse
threads.
Parting tool
For parting off, ie cutting off the waste, or dividing the workpiece
into sections.
Pin chuck
A chuck with a wooden or, more usually, a metal pin which is jammed
into a hole drilled in the workpiece.
Phloem
See 'Bast'
Pith
The narrow channel in the innermost part of the tree, its trunk, each
branch and twig,
Polyethylene
Glycol (PEG)
A pharmaceutical product which is sometime used by wood workers to
stabilise unseasoned timber. It is available in several grades - PEG
1000 is the grade used by wood workers. When unseasoned wood is
submerged in a solution of PEG 1000 the PEG is drawn into the wood by
the process of osmosis and replaces the water. Given sufficient time
the PEG will replace all the water in the wood. After the wood is
removed from the solution the PEG will set in the pores to prevent
shrinking cracking and distortion.
Precision Combination Chuck
A popular proprietary chuck
with attachments which can perform many of the functions performed by
the chucks listed here. It work on the basis of expanding or
contracting collets. Nowadays, scroll chucks are preferred.
Pummel
A section of the workpiece in spindle turning which is left square, eg
when turning legs for chairs or tables.
Rest
See tool rest.
Ring centre
A live or a dead centre in the tailstock which has a small point set in
the middle of a ring. The point locates the centre whilst the ring
bears on the surface of the workpiece thus limiting the penetration of
the wood. This helps to prevent splitting and is particularly useful
for built-up or split turnings. See also centres
Ring shake
See cup shake.
Roughing
out gouge (or roughing gouge)
Used in spindle turning for reducing square stock to round section. It
has a semicircular section and is ground square across. The bevel angle
should be around 35° to 45°. A roughing gouge is for spindle work and
should not be used for face turning, eg on bowls.
Ripple
Figure found in wood which has wavy grain, eg ripple sycamore. See also
fiddleback.
Rough
turning
There are two possible meanings for this expression.
• The reduction of a square piece of timber to a round section. This is
done with a roughing gouge.
• The preliminary work on turning a bowl. A beginner should never
use a roughing gouge for this.
Sapwood
This surrounds the heartwood. It transports the sap from the roots to
the leaves.
Saw cuts
When a log is converted to boards it may be cut in a number of ways.
The three terms most commonly encountered are:
• back sawn.
• through and through, and
• quarter sawn.
When back sawn the log is converted in such a way
as to provide the maximum number of cuts tangential to the growth
rings.
When quarter sawn the log is converted in such a
way as to provide the maximum number of cuts radial to the centre of
the log. Quarter sawn wood is usually more stable, ie less prone to
warping, shrinking and splitting, than that produced by other cuts.
Often, it also has a more attractive figure because of the oblique way
in which the medullary rays are cut, particularly in oak, sapele,
London plane (lacewood), and sycamore (fiddleback).
Through and through (often abbreviated
to T & T or T/T) refers to boards produced by simply sawing
through the log in a series of parallel slices. A log sawn this way
will produce some back sawn boards, some quarter sawn boards, and some
in between.
Sawtooth
machine bit
A special type of bit only used for drilling wood. It makes a hole with
a flat bottom except for a small centre mark. Sawtooth bits will cut
end grain and cross grain.
Scrapers
(Lathe) tools which
are designed to scrape the surface. Scraper tools are available with a
number of different plan shapes, such as round nose, V-tip and squared
off.
Scraping (cut)
Scraping cuts on the
lathe are specific cuts where the bevel of the tool is held clear of
the wood.
Screw chuck
A chuck with a single screw
fixed in the centre to which the workpiece can be attached.
Scroll chuck
A four-jaw chuck, now very
popular amongst woodturners. So named because the teeth on the
underside of the jaws engage in a raised spiral (ie scroll) on the
back-plate. Movement of the back-plate causes the jaws to move in or
out in unison.
Sealing
The first step in the finishing process. A sealer is applied to the
bare wood to act as a barrier to the ingress of moisture and dirt. It
also serves as a grain filler and as a base for further finishing
coats.
Seasoning
Drying green wood to a serviceable level.
• Air dried: dried by exposure to the air without the use of artifical
heat.
• Kiln dried: dried in a kiln (or oven) with the aid of artificial
heat.
Segmented
work
See laminated work.
Shake
See split.
Shallow
fluted gouge
See spindle gouge.
Shear cut.
This type of cut
occurs when the cutting edge is presented at an angle other than 90
degrees. Also called a "slicing cut".
Shell augur
bit
Used for drilling long holes on the lathes, eg in electric lamp stands.
Sizing tool
(or Hook gate)
A hook shaped attachment to a square parting tool which enables the
workpiece to be sized to a pre-set dimension. This is particularly
useful when an operation of this sort has to be performed repeatedly.
Skew chisel
A chisel on which the cutting edge is not square to the sides of the
tool.
Spalted wood
Wood which is in the first stages of fungal decay, ie rot. Very often
it is made manifest by irregular dark, or black, lines which run
through the material. It is most common in beech but is found in many
other hard woods. The fungae require damp conditions in which to grow;
when the wood is dried (below about 20% MC) the fungae die and the
process ceases.
Spigot
A parallel projection on the end of a workpiece which is made to fit
into a recess of some kind, eg a socket in a chair seat or in a spigot
chuck.
Spigot chuck
See cup chuck.
Spindle
gouge
Used for shaping spindle work, eg for turning beads and coves. It has a
cross section with a shallow arc; so is sometimes referred to as a
shallow fluted gouge. The cutting edge is usually ground to a finger
nail shape with a 30° - 40° bevel angle.
Split
A longitudinal fissure in the wood. Terminology may vary from place to
place but there can be said to be two types of split: namely, shakes
and checks. Shakes can occur in three main ways:
• in the living tree, possibly due to wind stress;
• at the time of felling, due to impact; and
• shrinkage in the log before conversion.
Checks occur after conversion of the log and are due to shrinkage
whilst the material is drying. See also: cup
shake, heart shake,
star shake, end check, surface check, through check and honeycomb.
Split
turning
A technique used where two identical semicircular items are required.
One method is to make a complete turning from solid stock and then saw
the piece in half. A better way is to glue two pieces of stock together
with a leaf of paper in the joint and then make the turning. When the
turning is complete the paper allows the pieces to be separated.
Spoon bit
A drill bit with a
spoon shaped cutting edge. This type of bit is used when drilling on
the lathe where the wood revolves and the spoon bit seeks the centre of
the turning wood.
Square
(wood)
A sawn piece of timber which is roughly square in section and ready to
be used in spindle turning.
Square nose
chisel
A chisel on which the cutting edge is square to the sides.
Star shake
A group of splits running away
from the pith in the form of a star.
Steady
A device that is
attached to the lathe bed and holds long turnings so that they can be
hollowed.
Swing
The largest diameter that can be turned over the ways,
Surface check
A split on the surface of the
wood.
T&T
(or T/T)
See saw cuts.
Tailstock
The movable assembly to the right of the headstock which slides along
the bed.
Tang
The tapered end of a woodturning tool which fits into the handle.
Through check
A split which extends through
a board from one surface to the other.
Ticketer
A round piece of metal used to form a burr.
Tool rest (or T rest)
Adjustable part of the lathe (usually a 'T' shape) which fits into the
banjo and supports the turning tool whilst work is in progress.
Waney
edge
A natural edge left by the outside of the tree on a sawn board.
Wire edge
See burr.
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