GLOSSARY
You can find glossary with terms, used in veneer productions here.
Adhesive — A substance capable of holding materials together by surface attachment. It is a general term and includes cements, mucilage and paste,
as well as glue.
Back — The side reverse to the face of a panel, or the poorer side of
a panel in any grade of plywood calling for a face and back.
Blending — Color change that is detectable at a distance of 6 feet to
8 feet (1.8 m to 2.4 m) but which does not detract from the overall appearance
of the panel.
Blister — Spot or area where veneer does not adhere. Blisters are considered
a bond line failure.
Bond — Grip of adhesive on wood at the line of application; bond line
or glue-line.
Book Match — Adjacent pieces of veneer from a flitch or log are opened
like a book and spliced to make up the face with matching occurring at the
spliced joints. The fibers of the wood, slanting in opposite direction in the
adjacent sheets, create a characteristic light and dark effect when the surface
is seen from an angle.
Brashness — Condition of wood characterized by low resistance to shock
and by abrupt failure across the grain without splintering (see ruptured grain).
Burl, Conspicuous — A swirl, twist or distortion in the grain of the
wood which usually occurs near a knot or crotch. A conspicuous burl is associated
with abrupt color variation and/or a cluster of small dark piths caused by
a cluster of adventitious buds.
Burl, Blending — A swirl, twist or distortion in the grain of the wood
which usually occurs near a knot or crotch but does not contain a knot and
does not contain abrupt color variation. A blending burl is detectable 6 feet
to 8 feet (1.8 m to 2.4 m) as a swirl or roundel.
Component (of face) — An individual piece of veneer that is jointed
to other pieces to achieve a full length and width face. Terms used interchangeably
with component in the context of the face and piece and leaf.
Core — The inner part of plywood between face and back, usually veneer.
Sawn lumber, particleboard, MDF, hardboard or other material is also used as
cores.
Core, Banded — Core that has been made with banding on one or more sides.
Crossbanding — Veneer used in the construction of plywood with five
or more plies. Crossbands are placed at right angles to the grain of the faces
and are typically placed adjacent to the face and back. Also refers to all
inner layers of veneer whose grain direction runs perpendicular to that of
the outer plies and includes parallel laminated plies.
Cross Break — Separation of the wood cells, often appearing as barely
distinct fine irregular lines across the grain. Such breaks are often due to
internal strains resulting from unequal longitudinal shrinkage or to external
forces.
Decay — The decomposition of wood substances by fungi. The incipient
stage is characterized by discoloration, and sometimes accompanied by a softening
of the wood substance. The final or ultimate stage is characterized by the
partial or complete collapse of the wood structure and the destruction of the
wood substance.
Defect, Open — Open checks, splits, joints, knotholes, cracks, loose
knots, wormholes, gaps, voids, or other openings interrupting the smooth continuity
of the wood surface.
Delamination — Separation of plies or layers of wood or other material
through failure of the adhesive bond.
Discoloration — Stains in wood substances. Common veneer stains are
sap stains, blue stains, stain produced by chemical action caused by the iron
in the cutting knife coming in contact with the tannic acid of the wood, and
those resulting from exposure of natural wood extractives to oxygen and light,
to chemical action of vat treatments or the adhesive components, and/or to
the surface finish.
Doze (Synonymous with Dote) — A form of incipient decay characterized
by a dull and lifeless appearance of the wood, accompanied by a loss of strength
and softening of the wood substance.
Face — The better side of any plywood panel in which the outer plies
are of difference veneer grades. Also either side of a panel in which there
is no difference in the veneer grade of the outer lies.
Few — A small number without regard to their arrangement in the panel.
Fill — A repair to an open defect, usually made with fast drying plastic
putty.
Gap — Open slits in the inner plies or improperly joined veneers.
Grain — The direction, size, arrangement and appearance of the fibers
in wood or veneer.
Grain Rupture — Veneer with slight breaks from improper cutting or irregular
grain.
Gum Pockets — Well defined openings between rings of annual growth,
containing gum or evidence of prior gum accumulations.
Gum Spots and Streaks — Gum or resinous material or color spots and
streaks caused by prior resin accumulations sometimes found on panel surfaces.
Hairline — A thin, perceptible line showing at the joint of two pieces
of wood.
Half-Round Slicing — Veneer cutting method. Half-round slicing is cutting
on an arc roughly parallel to the center of the log to achieve flat-cut veneer.
The cathedrals can have more rounded tops since the grain is formed by the
inner most growth rings as the veneer is cut through the flitch.
Hardwood — General term used to designate lumber or veneer produced
from temperate zone deciduous or tropical broad-leaved trees in contrast to
softwood, which is produced from trees which are usually needle bearing or
coniferous. The term does not infer hardness in its physical sense.
Heartwood — The non-active or dormant center of a tree generally distinguished
from the outer portion (sapwood) by its darker color.
Inconspicuous — Barely detectable with the naked eye at a distance of
6 feet to 8 feet (1.8 m to 2.4 m)-(see blending).
Joint — The common edge between two adjacent materials in the same plane.
Joint, Edge — Joint running parallel to the grain of the wood.
Joint, Open — Joint in which there is a space between two adjacent pieces
of veneer in the same plane.
Knot — Cross section of tree branch or limb with grain usually running
at right angles to that of the piece of wood in which it occurs.
Knot, Open — Opening produced when a portion of the wood substance of
a knot has dropped out, or where cross checks have occurred to produce an opening.
Knotholes — Openings produced when knots drop from the wood in which
they were embedded.
Knots, Blending Pin — Sound knots 1/4" (6.4mm) or less that generally
do not contain dark centers. Blending pin knots are barely detectable at a distance of 6 feet to 8 feet
(1.8 m to 2.4m), do not detract from overall appearance of the panel, and are
not prohibited from appearing in all grades.
Knots, Conspicuous Pin — Sound knots 1/4" (6.4mm) or less in diameter
containing dark centers.
Knots, Sound, Tight — Knots that are solid across their face and fixed
by growth to retain their place.
Lap — A condition where one piece of veneer in the same ply overlaps
another piece.
Lauan — species of the same genera as Philippine mahogany, but not specifically
limited to trees of the Philippine origin. (See Philippine mahogany).
Layer — A single veneer ply or two or more plies laminated with grain
direction parallel (see ply). Two or more plies laminated with grain
direction parallel is a parallel laminated layer.
Lengthwise Slicing — Veneer cutting method. A board of flat sawn lumber
is passed flat over a stationary knife. As it passes, a sheet of veneer is
sliced from the bottom of the board. This produces a variegated figure.
Loose Side — In knife-cut veneer, the side of the sheet that was in
contact with the knife as the veneer was being cut, and containing cutting
checks (lathe checks) because of the bending of the wood at the knife edge.
Mismatched (MM) — Mismatched refers to a face where adjacent veneers
are joined at random without regard to grain figure and/or color. Most commonly
produced mismatched faces consist of six to eight separate pieces of plain
sliced or rotary cut veneer, selected at random, joined, then grooved upon
the joint to simulate lumber paneling.
Moisture Content — The weight of the moisture in wood, expressed as
a percentage of its ovendry weight.
Occasional — A small number of characteristics that are arranged somewhat
diversely within the panel face.
Patches — Insertions of fillers or sound wood placed and glued into
panels from which defective portions have been removed or are missing.
Philippine Mahogany — A trade term used to describe any of the seven
species of woods grown in the Philippine Archipelago (tanguile, red lauan,
white lauan, tiaong, almon, mayapis, batikan). Use of the term “mahogany” without
the qualifying work “Philippine”, or use of the term “Philippine
mahogany” to describe Philippine woods other than those named above or
to describe woods not grown in the Philippine Archipelago although of the same
genera or family, may be an unfair trade practice with prohibition of Section
5 of the Federal Trade Commission Act.
Plain Sliced (Flat Cut) — Veneer cutting method. Veneer sliced parallel
to the pith of the log and approximately tangent to the growth rings to achieve
a flat-cut veneer. Plain sliced veneer is cut using either a horizontal or
vertical slicing machine or by the half-round method using a rotary lathe.
Pleasingly Matched — A face containing components which provide a pleasing
overall appearance. The grain of the various components need not be matched
at the joints. Sharp color contrasts at the joints of the components are not
permitted.
Ply — A single sheet of veneer, or several strips laid with adjoining
edges, that may or may not be glued, which forms one veneer lamina in a glued
panel (see layer). In some constructions, a ply is used to refer to other wood
components such as particleboard or MDF.
Plywood, Hardwood — A panel composed of an assembly of layers or plies
of veneer, or veneers in combination with lumber core, particleboard, MDF core,
hardboard core, or of special core material, joined with an adhesive. Except
for special construction, the grain of alternate plies is at right angles,
and the face veneer is a hardwood species.
Putty — A plastic substance used to fill open defects (see fill).
Quarter Slicing — Veneer cutting method. Quarter slicing achieves a
straight grain appearance by slicing perpendicular to the annual growth rings.
Random Matched — see mismatched.
Repairs — A patch, shim, or filler material inserted and/or glued into
veneer or a panel to achieve a sound surface.
Repairs, Blending — Wood or filler insertions similar in color to adjacent
wood so as to blend well.
Ribbon Striped (Ribbon Grain) — The ribbon effect produced by quarter
slicing woods with interlocking grains.
Rift Cut — Veneer cutting method. Rift-cut veneer is produced from the
various species of oak. Oak has medullary ray cells which radiate from the
center of the log like the curved spokes of a wheel. This straight grain cut
is at a slight angle to the medullary rays in oak to minimize ray fleck (flake).
Rotary Cut — Veneer cutting method. Veneer produced by centering the
log in a lathe and turning it against a broad cutting knife which is set into
the log at a slight angle. Rotary cut veneer can be sufficiently wide to provide
full sheet (one piece) faces.
Rough Cut — Irregular shaped areas of generally uneven corrugation on
the surface of veneer, differing from the surrounding smooth veneer and occurring
as the veneer is cut by the lather or slicer.
Sapwood — The living wood of lighter color occurring in the outer portion
of a tree, sometimes referred to as sap.
Shake — A separation or rupture along the grain of wood in which the
greater part occurs between the rings of annual growth.
Shim — A thin, often tapered piece of wood used to fill in the space
between things.
Sliced — Veneer produced by thrusting a log or sawed flitch into a slicing
machine which shears off the veneer in sheets.
Slight — Visible on observation, but does not interfere with the overall
aesthetic appearance with consideration of the applicable grade of the panel.
Smooth — Of even and level surface.
Smooth, Tight Cut — Veneer cut to minimize lathe checks.
Species (Trees) — An internationally established Latin botanical classification
of trees.
Splits — Separations of wood fiber running parallel to the grain.
Streaks, Mineral — Natural discoloration of the wood substance.
Swirls — Irregular grain usually surrounding knots or crotches.
Tape — Strips of gummed paper or cloth sometimes placed across the grain
of large veneer sheets to facilitate handling and sometimes used to hold the
edges of veneer together at the joint prior to gluing.
Telegraphing — Visible irregularities in the surface of the face of
plywood caused by corresponding irregularities in the underlying plies such
as core laps, voids, or extraneous matter.
Tight side — In knife-cut veneer, the side of the sheet that was farthest
from the knife as the sheet was being cut and containing no cutting checks
(lathe checks).
Veneer — A thin sheet of wood, rotary cut, sliced or sawed from a log,
bolt, or flitch.
Vine Streaks (Marks) — Scars in the wood generally caused by the stems
of clinging vines or by their hair-like air roots which cling to the tree trunk.
Live vine streaks produce sound scars. Dead vine streaks contain either dead
residue of the vine, or the remaining pocket similar to bark pocket. Also referred
to as chicken tracks.
Wood Filler — An aggregate of resin and strands, shreds, or flour of
wood which is used to fill openings in wood and provide a smooth, durable surface.
Wormholes — Holes resulting from infestation of worms.
Worm Track or Scar — The groove or resulting scar tissue in the wood
caused by worms or other borers.
Definition References:
Product Standard for Imported Wood Veneer and Platforms (IHPA–2000)
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