| Term |
Description |
| Plate |
A
horizontal framing member laid flat. |
| Plate
Joint Ñ |
A
butt joint that is reinforced with a football shaped
"biscuit". The biscuits are usually made from compressed
pieces of wood, usually birch. When a biscuit comes into
contact with glue in the joint it swells creating a tighter
joint. Also called a Biscuit Joint. |
| Plumb |
Straight
up and down, perfectly vertical. |
| Plunge
Router |
A
router mounted on a spring loaded base. The router can
be turned on and plunged down into the workpiece. |
| Ply |
One
layer of a laminated sheet. |
| Plywood |
An
assembled product made up of veneers of timber glued
together so that the grain of alternate layers is at
right angles. |
| Plywood |
Sheets
of wood consisting of three or more sheets of wood glued
and bonded by heat and pressure with the grain of each
sheet running perpendicular to adjacent layers. |
| Pocket |
A
patch of bark or gum (kino) completely or partially enclosed
in the wood. |
| Pole |
A
round timber column. |
| Poly
under top tier (PUTT) |
A
way of giving some protection to unitized lumber by the
insertion of a piece of plastic between the next to top
and top tiers. |
| Porous
Wood |
Wood
with larger than normal pores and vessels |
| portal
frame |
A
planar frame where the lateral and bending forces are
transferred by moment resisting connections from the
portal rafters to the columns. |
| Post
and beam structure |
A
structural frame with repetitive columns and beams. |
| Precision
end trimmed (PET) |
Lumber
trimmed smooth on both ends and varying no more than
1/16Ó in no more than 20% of the pieces. |
| Precision
end trimmed (PET) |
Lumber
trimmed smooth on both ends and varying no more than
1/16" in nor more than 20% of the pieces. May be a condition
of sale. |
| Preservative |
Any
substance that is effective in preventing , for a reasonable
period of time, the development and action of fungi,
borer and insect attack in wood. |
| Preservative |
Any
substance which can be introduced into wood to prevent
the development or action of decay or deterioration by
insects and other organisms for a reasonable length of
time. |
| PressureÑ |
treated
lumber Lumber that has been saturated with chemicals
to prevent rot or decay caused by living organisms. |
| Price
at the time of shipment (PTS) |
an
order committed to by both the buyer and seller, but
not having a firm price until it is ready for shipment. |
| Primary
Wood Products |
Include
logs, softwood lumber, hardwood lumber, plywood, oriented
strand board (OSB), medium-density fiberboard (MDF) and
particle board. |
| Procurement
forester |
A
forester employed by and accountable to a sawmill or
paper mill and who is responsible for providing a continuous
supply of logs for his/her employer. Also referred to
as industrial foresters, they purchase trees on the stump
or at the landing from landowners or loggers. |
| Proportional
Limit |
Refers
to the maximum load that marks the limit beyond which
there is no more direct proportionality between applied
load and deformation produced, during mechanical testing
of a material. |
| Pruning |
Pruning
of lower dead branches leads to an almost immediate improvement
in the quality of wood produced. After several years
new wood will cover the severed branch stubs and the
subsequently produced wood will be knot-free. This treatment
has no effect upon tree growth. Pruning can significantly
improve the quality of saw and veneer logs. For maximum
effectiveness pruning should be concentrated on lower
portions of larger trees which will not be harvested
for some 30 to 40 years following treatment. Heavy pruning
which removes a substantial portion (i.E., More than
one-third) of the green crown should be avoided. |
| Pulp
logs |
Logs
of lesser value (smaller in diameter with acceptable
defects) than sawlogs, of greater value than cordwood.
Pulp logs are usually bought by the ton to be debarked,
reduced to chips, and used to manufacture pulp and paper. |
| Pulp
Trees |
Small
trees and saplings that will be ground to produce paper.
Lumber farmers often over-plant their acreage and remove
smaller trees for pulp as the crop matures. |
| Pumice Ñ |
A
fine abrasive powder that is made from volcanic ash.
Pumice is used with a a felt block in woodworking to
rub out (polish) a finish. (Pumice is also the gritty
additive in Lava soap.) |
| Purlin |
One
of a series of horizontal framing timbers supporting
the rafters or spanning between trusses or frames and
supporting the roof. Purlins usually span at right angles
to the slope of the roof |
| Push
Stick |
A
tool used to safely push a board through a table saw
or other power tool. |
| Quarter
cut |
A
method of slicing veneers whereby the average inclination
of the growth rings to the wide face is greater than
45 degrees. |
| Quarter
sawn timber |
Timber
in which the average inclination of the growth rings
to the wide face is not less than 45 degrees. |
| Quarter-sawn |
A
method of cutting lumber where the annual rings are relatively
perpendicular to the face of the board. Quarter-sawn
lumber tends to be more dimensionally stable than other
forms of lumber, such as plain-sawn. |
| Quarter-sawn |
Wood
that has been sawed so that the wide surfaces extend
approximately at right angles to the annual growth rings.
Same as edge-grained lumber. |
| Queen
Anne |
A
style of furniture that was first made popular in England
during the rule of Queen Ann. It was used almost exclusively
by early colonial cabinetmakers. The Cabriole Leg is
one of the primary characteristics of the Queen Ann style. |
| Rabbet |
A
cut partway through the edge of a board that is used
as a part of a joint. |
| Radial |
Coincident
with a radius from the axis of the tree or log to the
circumference. |
| Radial
Shrinkage |
Shrinkage
in a piece of lumber that occurs across the growth rings
as it begins to dry. |
| Radially
sawn |
timber
sawn on the radius from the central axis of the tree
or log to the circumference, perpendicular to the growth
rings. The resulting pieces are generally triangular
in shape. |
| Rafter |
One
of a series of roof support timbers that provide principal
support for the roofing material. Rafters usually span
parallel to the slope of the roof. |
| Rail |
(1)
A horizontal board that runs along the underside of a
table. (2) The horizontal part of a raised panel door. |
| Raised
Grain |
A
roughened condition of the surface of dressed lumber
in which the hard latewood is raised above the softer
earlywood but not torn loose from it. |
| Raised
Panel |
A
piece of wood that is the center of a frame and panel
assembly. |
| Random
lengths |
A
lumber tally containing various lengths. |
| Ray |
A
ribbon like figure caused by the strands of cells which
extend across the grain in quarter sawn lumber. |
| Rays |
A
ribbon-like arrangement of cells, usually oriented in
the radial direction. |
| Reaction
Wood |
Abnormal
wood formed in a leaning tree, often characterized by
a dense hard brittle grain and propensity to react irregularly
to seasonal moisture changes. In hardwood trees, it forms
on the upper side of the lean and is called tension wood.
In softwood trees it forms on the lower side of the lean
and is called compression wood. |
| Reaction
wood |
Reaction
wood is wood formed in trees where the main stem is tipped
from the vertical. It also often forms following the
deflection of a lateral stem (branch) from its normal
orientation. Reaction wood formed in hardwoods differs
from that formed in softwoods. In softwoods, reaction
wood is called compression wood; reaction wood in hardwoods
is called tension wood. Both compression wood and tension
wood are lower in quality than normal mature wood. As
with juvenile wood, reaction wood is viewed as least
desirable in lumber and in other products in which wood
is used in solid form. |
| Reaction
Wood |
Wood
with more or less distinctive anatomical charateristics,
usually formed in parts of leaning or crooked stems and
in branches. It is referred to as tension wood in hardwoods
and compression wood in softwoods. |
| Recessing
and Routing |
The
ease or difficulty with which
a timber can be slotted,
rebated or routed. |
| Reconditioning
treatment |
A
high temperature/high relative humidity (100%) treatment
applied after drying to restore the shape of collapsed
or distorted wood. |
| Reforestation |
The
natural or artificial restocking of an area with forest
trees. |
| Refractory |
In
timber drying this term is used to indicate high resistance
to moisture loss during drying. |
| Refractory
Wood |
Wood
that is difficult to dry, impregnate with preservatives,
machine, or to process or manufacture through conventional
methods. |
| Relative
humidity |
At
a given temperature, this is the amount of moisture in
air as a percentage of the maximum moisture carrying
capacity of the air, i.E. The water vapour pressure as
a percentage of the saturated water vapour pressure. |
| Relative
Humidity |
Ratio
of the amount of water vapor present in the air to that
which the air would hold at saturation at the same temperature. |
| Resawing |
The
process of sawing lumber in two lengthwise, parallel
to the wide face. It is usually, though not always, done
through the middle of the board, producing two equal
sized boards, each approximately half the thickness of
the original. Resawing changes the thickness of the lumber
but not its width. Also see Ripping. |
| Resin |
Inflammable,
water-soluble, vegetable substances secreted by certain
plants or trees, and which characterize the wood of many
conifers. |
| Resin
Ducts |
Tubular,
intercellular spaces which contain and transmit resinous
material. |
| Resistance
to Impregnation or Treatability |
The
natural resistance of wood to attack by fungi and insects
can sometimes be improved from low to average, or even
better through preservative treatment. Extent of improvement
is dependent upon the treatability or the ability of
the wood to absorb and retain suitable preservatives
in adequate amounts. Treatability varies significantly
between species and between sapwood and heartwood of
the same species. Classifications usually refer to the
heartwood only and should be applied with caution since
methods of determining treatability are not standardized. |
| Resorcinol
glue |
An
adhesive made from resorcinol resin and formaldehyde. |
| Reveal |
The
surface left exposed when one board is fastened over
another; the edge of the upper set slightly back from
the edge of the lower. |
| Ribbon
figure |
A
striped figure produced by cutting timber that has an
interlocked grain. Also called striped figure. |
| Ridge |
The
highest part of the roof at the meeting of the upper
ends of the common rafters. |
| Rip |
To
cut along the grain. |
| Riparian |
Related
to or living or or located on the bank of natural watercourse,
such as a stream or river or lake or tidewater. |
| Ripcut
(Ripping) |
A
cut made parallel to the grain of a board. See - Crosscut
(crosscutting) |
| Ripped
and bundled |
A
remanufacturing process in which lumber is ripped and
then minor bundled. |
| Ripping |
the
process of cutting lumber in two, perpendicular to its
wide face. For example, making a 2x12 into two pieces
of 2x6. |
| Ripping |
The
process of sawing lumber in two lengthwise perpendicular
to the wide face. Ripping changes the width of the lumber
but not its thickness. Also see Resawing. |
| Roof
batten |
Small
timbers fixed to the top of rafters to which the roofing
material is secured. |
| Ropey
figure |
Markings
in the form of a twisted rope. |
| Rotary-cut
veneer |
Veneer
cut in a lathe which rotates a log chucked in the centre
against a knife. This method of peeling is used to produce
decorative veneers and is a common method of manufacturing
veneers for plywood. |
| Rotary-cut
Veneer |
Veneer
which was cut from a log in one long sheet. Rotary cut
veneer is cut from a log like a roll of paper towels. |
| Rotation
age |
The
period of years required to establish and grow a timbercrop
to a specified condition of maturity. The intended age
of harvest of mature trees. Long rotations mostly affect
those features that are desirable in lumber and in structural
and non-structural products made largely of wood in solid
form. Harvest age has less impact on the usefulness of
wood for use in paper and fiber products and in products
in which wood is reduced to small pieces prior to manufacture. |
| Rough
sawn |
Surface
condition of wood as it leaves the saw, i.E. Not dressed
or final sawn. |
| Round
timber |
Timber
used in the original round form, such as in poles, posts
or bridge beams. |
| Round-Edge
Lumber |
Boards
having attached bark on both edges. |
| Rout |
To
cut out by gouging. |
| Rub
Bearing |
A
ball bearing rub collar near the top or bottom of a spindle
shaper that is used to keep the workpiece a fixed distance
away from the cutters. |
| Rule
Joint |
A
joinery method used in drop leaf tables where the tabletop
has a convex profile and the leaf has a concave cut.
The two pieces are joined by a hinge. |
| Runout |
The
amount of wobble in a shaper or router. |
| Salvage |
To
harvest trees that are dead or in poor condition but
can still yield a forest product. |
| Sanitation
cutting |
The
removal of damaged or diseased stems to prevent the spread
of insects or disease. |
| Sap |
The
water in a tree which is rich in minerals and nutrients. |
| Sapling |
A
young tree of small diameter, typically 2 to 5 inches
at DBH. |
| Sapwood |
The
new wood in a tree that lies between the bark and the
Heartwood. Sapwood is usually lighter in color and becomes
heartwood as the tree ages. Also see heartwood. |
| Sapwood |
Outer
layers of wood which, in a growing tree, contain living
cells and reserve materials such as starch. Under most
conditions the sapwood is paler in colour and more susceptible
to decay than heartwood. |
| Sapwood |
The
layer of new wood surrounding the denser, dead heartwood
of a tree and under the cambium and bark layers. |
| Sawed
veneer |
Veneer
produced by sawing |
| Sawn
timber |
Timber
finished to size with a saw. |
| Scaling
(lumber or logs) |
Logs
are measured (or scaled) for the purpose of estimating
the amount of lumber that can be obtained. Once logs
have been processed into lumber it is again necessary
to quantify volumes produced. The process of measuring
lumber is called lumber scaling. The volume lumber yielded
from a log may be greater than the estimated volume of
lumber. Also see Yield. |
| Scarf
joint |
A
joint made by bonding two matching bevelled ends or edges. |
| Scarf
Joint -Picture |
A
woodworking joint that is made by cutting or notching
two boards at an angle and then strapping, gluing, or
bolting them together. |
| Schoolmarm |
Logger's
slang for a tree with one or more trunks. |
| Scientific
Certification Systems (SCS) |
One
of two independent organizations inthe U.S. Appointed
by the Forest Stewardship Council to certify landowners
engaged in active forest management. SCS is based in
Oakland, CA and is a for profit operation. The other
agency is Smartwood based in Manchester, VT. |
| Scrag
mill |
A
special high-speed sawmill designed to saw small diameter
logs. A skrag mill typically has two circle saws arranged
in parallel which remove two slabs with one pass of the
log producing a two-sided cant. Not all sawmills have
a scrag capability and so are limited to purchasing only
larger diameter sawlogs. |
| Scribe |
To
mark for an irregular cut. |
| Scribner
Log Rule |
In
use since before 1846. This scaling rule is based on
a diagram of the size and number of 1" boards that could
be sawn from it allowing for 1/4" kerf. |
| Seasoned
timber |
Timber
that has been dried so that the maximum moisture content
anywhere in the piece does not exceed 15%. |
| Seasoning |
Drying
timber to a moisture content appropriate to the conditions
and purposes for which it is to be used. |
| Seasoning |
The
process of removing the moisture from green wood to improve
its workability and stability. |
| Seasoning
or Drying |
Removing
moisture from green wood
to improve its serviceability. |
