DT Wood

Wood and its products can be seperated into 3 categories.

• HARDWOODS
• SOFTWOODS
• MANUFACTURED BOARDS

All are produced from naturally growing trees but MANUFACTURED BOARDS ARE MAN-MADE using natural timber BUT THEY ARE NOT CLASSED AS WOOD.

DECIDOUS TREE

• Warmer climates
• Hardwoods mainly grow in the southern hemisphere of the world, often tropical climate
• .Grow slowly, reaching maturity in about 70 years.
• Thousands of species Grown in places like Europe, New Zeland and Japan.
• Most lose their leaves each year
• Generally more durable than softwoods.
• Wider variety of colour and texture.
• Exotic woods made into veneers allowing greater use of limited supplies.

CONIFEROUS TREE

• Colder climates.
• Mainly grow in northern hemisphere.
• Grow quickly reaching maturity in around 30 years.
• Trees with needle like leaves.
• Straight trunks meaning less waste.
• Often grow in managed forests.
• Cheaper than hardwoods.
• Waste is used for manufactured boards and paper.

OAK : Hardwood. From Europe, Japan & USA. Very hard, tough, strong and durable. Little shrinkage. Contains acid that corrodes steel.Easy to work. Used for garden benches quality furniture.

MAHOGANY: Hardwood. From American and Africa. Durable, good finish, prone to warping, fairly easy to work. Used in window frames and interior furniture.

BEECH: Hardwood. From Europe. Hard, tough, very strong and straight. Good finish, turns well. Prone to warping. Used for workshop benches, toys and interior furiture.

ASH: Hardwood. From Europe. Tough, flexible (good elastic properties). Works and finshes well. Used for sports equiptment, ladders, tool handles and laminated furniture.

ELM: Hardwood. From Europe. Tough, durable,fairly strong. Turns well, prone to warping. Used for garden furniture, interior furniture and wood turning.

SCOTS PINE: Softwood. From North Europe. Knotty and prone to warping. Used for floorboards and toys.

PARANA PINE: Softwood. From S America.Hard, straight grain, durable, smooth finish. Easy to ork, usually knot free. Used for quality softwood joinery.

WHITEWOOD: Softwood. From N Europe, USA and Canada. Fairly strong but not durable. Easy to work, resistant to splitting. Used for general interior work. 

Are man-made and often use unwanted products of woods. Sections of timber, thin veneers or wood particles glued together and compressed.

ADVANTAGES :

• Come in wide boards, wider than timber.
• Can cover large areas at a cheap cost.
• In plywood, alternating grains at 90degrees increases strength.
• A lot cheaper than natural timber.
• Veneers can be used to cover unplesent surfaces.

DISADVANTAGES

• Screws and nails find it hard to stay attatched.
• Edges and surfaces can be unplesant.
• Some split easily and absorb water and are hard to seal and finish.
• Dust from boards like MDF are dangerous to inhale.

Involves the application of many coats. Before painting, wood should be sealed with shellac.

Painting is a time consuming finishing process.

• OIL BASED- known as glossy paints. Available in a wide range of colours. Durable and waterproof. Used on windows, doors and boats.
• EMULSION- Available in Vinyl or acrylic resin. Water based but not waterproof.
• POLYURETHANE- Tough and scratch resistant. Harden wghen exposed to air. Commonly used on childrens toys.

Varnishes are plastic type of paint made from synthetic resins. When dried, they provide a tough waterproof and heatproof finish to the wood or manufactured board surface.

• POLYURETHANE- Come in a wide variety of colours and different finishes (matt, gloss or satin.) Best applied in thin coats and rubbed down between each coat with glass paper.
• ACRYLIC - Relativly new in comparison to Polyurethane. Dry faster and have less odour. The brushes can be cleaned in water not solvent. More enviromentally friendly.