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- Plantation forestry has developed rapidly in New Zealand. In 50
years, the country's industrial wood supply has changed almost
completely from natural forests to managed forest plantations,
thus emphasising New Zealand Pine as the primary species.
- Extensive research and experience in plantation forestry has provided
a good understanding of how New Zealand pine log quality can be
influenced by genetic selection, silviculture and the method of
conversion.
- New Zealand pine has unique properties among softwood species,
in that total treatment of sapwood is always achievable. It is
very amenable to manipulation of preservative treatment processes,
which are environmentally acceptable and give a reliable standard
of treatment.
- New Zealand pine sawn lumber is a versatile structural building
material which is well suited to the 2 x 4 building system. It
is used equally successfully in larger buildings as glue-laminated
lumber and for many other structural applications.
- New lamination and finger-jointing technologies are increasing
the use of New Zealand pine in a wide range of products - from
small mouldings to huge engineered beams.
- New Zealand pine is being successfully used for a wide range of
interior fittings and fixtures, including: windows, doors, frames
and jambs, mouldings, stairs, cabinetry and bench tops.
TREATMENT
Preservative treatment to the strict hazard class specifications,
allow the New Zealand industry to give service life guarantees
for external use products.
A number of properties of New Zealand pine contribute to the ready
acceptance for these products.
TEXTURE & APPEARANCE
One of its unique properties is its uniform density, i.e. the
small variation in density between spring wood and summer wood
within a growth ring. It is this property which confers on New
Zealand pine its excellent machining, painting and staining properties.
Consisting mainly of white sapwood, with prominent fine resin
canals, it presents a uniform appearance with little colour variation
between pieces. This is an advantage for subsequent finishing.
MACHINING
Comprehensive tests undertaken have shown that New Zealand pine
has machining properties (cross-cutting, turning, planing, moulding,
boring, sanding) equal to or superior to many of the internationally
traded softwoods. Its fast growth does not adversely affect its
working properties and good results can be obtained with all types
of hand and machine tools.
FINISHING
The full range of interior and exterior stains, oils, varnishes
and paints may be used on New Zealand pine. The absence of high
concentrations of extractives prevents any incompatibility with
finishes and eliminates the need for special primers. A very high
standard of finishing can be obtained.
The wood can be stained to resemble a wide range of traditional
timber species.
FASTENING
Being of medium density and even texture and having a good resistance
to splitting, New Zealand pine can be nailed particularly well.
The same properties allow the production of efficient joints using
other systems, e.g. screws and proprietary connections.
Low extractives content and uniform density allow achievement
of above-average glued connections e.g. dowels and finger-joints.
The high strength of glues dowel joints is due to the contribution
from the end grain to the joint.
DIMENSIONAL STABILITY
This is a crucial wood property for interior fittings and joinery
uses. New Zealand pine has a low shrinkage which contributes to
its stability.
However, stability is also affected by a number of other properties,
including: equilibrium moisture content, straightness of grain,
spiral grain, rate of moisture uptake, permeability to liquids
and gases.
Long term movement is the property which best describes the dimension
changes which occur when joinery is exposed to dry summer conditions
and later to wet winter conditions.
The dimensional response of cladding and joinery when exposed
to fluctuating weather conditions, such as alternating rain wetting
and sunshine, is best described as short-term movement.
Because of the presence of spiral grain, the juvenile wood of
New Zealand pine should not be used where stability is vital to
performance.
Dimensional performance can be increased by use of finger-jointing,
and/or lamination. Such highly processed laminated, finger-jointed
clear products are used widely in Japan where a maximum stability
is required.
DURABILITY
New Zealand pine must be preservative-treated for exterior uses.
However, it is one of the most permeable wood species and can,
therefore, be acceptably treated by pressure impregnation, double
vacuum and simple immersion methods. LOSP treatments are very
successful for joinery.
WOOD BENDING
A process developed to bend solid pine timber and MDF to the consistent requirements
of furniture manufacturers, thus creating an entire range of design possibilities.
The Woodform process is both cost and time effective for the manufacturing of existing
products, and it creates the potential for more inspired, imaginative furniture design
and production; options previously uneconomic now achieve maximum value added potential.
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