Natural and manufactured timber
Natural timber
Natural timber is classified into two groups:
Softwood = timber that comes from coniferous trees:
Evergreen
Trees have needles rather than leaves
Quick growing
Seeds are housed in cones
Extensively used in joinery
Generally less expensive than hardwood
Generally has poor resistance to decay
Types and uses of softwood:
Larch:
Appearance - Reddish in colour with an open grain
Characteristics - Good resistance to rot
Uses - Garden fences and patio decking
Pine:
Appearance - Yellow in colour with a contrasting darker grain
Characteristics - Contains many knots
Uses - Interior joinery and furniture
Spruce:
Appearance - Creamy white in colour
Characteristics - Close grain and lightweight
Uses - Interior furniture and stringed musical instruments
Hardwood = timber that comes from deciduous trees:
Trees lose their leaves in winter
Trees have broad leaves
Slower growing than softwood
Seeds are housed in fruits
Generally more expensive than softwood
Generally has good resistance to decay
Types of hardwood:
Oak:
Appearance - Light to medium brown with sometimes a yellow or reddish tint
Characteristics - Hard, tough and durable
Uses - Timber-framed buildings and high-quality furniture
Beech:
Appearance - Pale cream to light pinkish-brown
Characteristics - Hard, strong and does not splinter
Uses - Children’s wooden toys, benches, furniture and tool handles
Mahogany:
Appearance - Attractive, deep reddish brown colour
Characteristics - Easy to work
Uses - High-quality furniture
Sources and finishes of natural timber:
Comes from trees so limited in maximum size of the pieces
Comes in many forms: planks, boards, strips, square and dowel
Can be finished with oils, waxes, varnishes and paint
Designed to give some protection from moisture and weather
Can also be used to improve aesthetic qualities of the materials
Manufactured timber
Manufactured timber is classified into two groups:
Laminated boards -
Several layers (veneers) of wood glued together
Compressed boards -
Particles, chips or flakes of wood that are glued together under pressure
Advantages of manufactured timber:
Available in large sheets (2440mm by 1220 mm)
Consistent properties
Less likely to twist, warp or split
Some use recycled or low-grade timber
Can be faced with veneer to improve its aesthetic appearance
Can be protected using finishes to give waterproofing qualities
Can be faced with a polymer laminate to improve its working properties
Suited to CNC machining
Types and uses of manufactured timber:
Plywood -
Appearance - Smooth and flat but edges show visible layers
Characteristic - Several layers of veneers, glued with the grain placed at 90 degrees to the next layer
Uses - furniture, flooring, roofing and boat building
MDF (medium density fibreboard)-
Appearance - Light brown or tan in colour and very smooth/flat with no knots or grain patterns
Characteristics - Made from fine fibres of low-grade wood that is glued under pressure with a formaldehyde resin
Uses - Self-assembly furniture
Chipboard -
Appearance - Light brown or pale beige in colour made up of visible wood chips pressed together
Characteristics - made from chips of low-grade wood that is glued together under pressure
Uses - Kitchen worktops