- More knots allowed
- Streak, marks, veneer laps, unlimited small defects
- Any matching
Backs: The reverse
side to the face of a plywood panel.Generally, the poorer side of any grade
plywood panel calling for a face and a back.
Bark Pocket: A small area of
bark around which normal wood has grown.
Burl: A swirl or twist in the
grain of wood, usually occurring near a knot, but which itself does not contain
Core: The innermost portion of plywood usually composed
of veneer. Also referred to as a "center." A core may also be made of
fiberboard, particleboard or lumber.
Crossbar: An imperfection or
irregularity in the grain of wood running at right angles to the length of the
Crossbanding: Inner ply veneer placed at right angles
to the core, face and back of a plywood panel.
Defects: Anything interrupting the smooth flow of a wood surface.
This includes loose knots, splits, voids, wormholes, bark pockets and others.
Delamination: The separation of the inner plys in a panel due to the
failure of the adhesive bond.
Face: The best side of a plywood panel in which the outer veneers are
of different grades.
Grain: The pattern, size and direction of the
fibers in wood or veneer.
Gum Spots: Accumulation of resinous material often found on panel
surfaces. May be removed by sanding.
Half-Round Slicing: Off-center slicing cut slightly across the annular
grown rings resulting in half-round, plain sliced or rotary characteristics.
Hardwood: General term referring to the wood of many different
deciduous trees as opposed to the softwood of evergreen or coniferous trees. Does
not relate to the density of the wood.
Knot: Circular portion of a
board or veneer that was once the base of a branch or twig growing from the
trunk of a tree.
Knot (Open): Opening produced when a portion of a know has dropped out or
separated due to seasoning.
Knot (Pin): Sound knots less than 1/4" in diameter.
Knot (Sound): Knots that are
solidly fixed by growth and retain their place in lumber or veneer.
Knothole: Opening produced
when knots drop from the wood in which they were once embedded.
Lap: The overlapping of one
piece of veneer on another in the same layer of ply.
Medium Density Fiberboard
(MDF): A panel or core
material manufactured from pressure cooked wood fiber, resin and wax.
Mineral Streak: A
discoloration of hardwood and hardwood veneer.
Particleboard: A panel or core material manufactured
from pressed sawmill shavings, resin and wax.
Patches: Filler material
inserted into defects of veneers or panels for repair.
Plain Sliced: Veneer sliced
from a log tangent to the tree's annual rings.
Ply: A single sheet of veneer
forming one layer in a multi-layered piece of plywood.
Plywood, Hardwood: A panel
composed of layers of inner plys, or other core material joined with an adhesive
to a face veneer of hardwood and a back veneer, usually also composed of
Quarter Slicing: Quartered log
sliced at right angles to the growth rings.
Rift Cut: Veneer cut from a
quartered log on a 90 degree angle to the grain.
Rotary Cut: Veneer peeled from a whole log set in a lathe
and turned against a special knife
Sapwood: The light colored,
living portion of a tree located between the heartwood and the bark.
Slip Matched: Veneer sheets
that are laid side by side to form a whole sheet with a repetitive grain
Splits: Separations of the
wood fiber running parallel to the grain.
Veneer: Peeled or sliced thin sheets of
wood used as inner plys or as decorative faces.