Technology

They are source from broad-leaved and deciduous tree. Hardwod tends to be slower growing as they reach maturity of 100 years. As a result they are more expensive than softwood. e.g.

Mahogany- reddish brown  with generally straight grain. Used for cabinets,furniture, muisical instrument

Oak- rich, light brown wood with straight grain. Used for contructions, furniture, staircase

Softwood comes from coniferous trees, often they have pines or needles and they stay evergreen all year round. The growth rate is faster, reaching maturity of 30 years. As a result they are much cheaper to buy and are a sustainable material. e.g. cedar, yew, pine.

Redwood- usually called the scotspine, fairly strong and stable. Pale yellow with brown streak. Used for construction, fencing, outdoor decking

Parana Pine- hard, expensive than softwood, straight grain and knot free. For interior use like staircase, doors, built in furniture.

Made from waste-produced, when trunks and branches of trees are cut into planks. They are no prone to defects and are not affected by humidity. A venner is thin layer of real wood used to cover board and they are helpful to improve their appearance. They dont have a grain structure. Its easier to work than natural wood. They can be easily joined with knock down fittings. 

MDF- smooth, light brown and can be veneered, For indoor use like kitchen, flat pack furniture etc

Plywood- high strength, flexible, easy o cut. They can be stained, painted for shelving, toys.

Chipboard- compacted wood chips, laminated with a variety of coverings, end cuts are difficult to finish. For veneered worktops, floorings etc

Taking one type of motion & force and change into another type of motion & force.

Makes a job easier

e.g. levers, linkages, cams, gears and pulleys.,

Natural Plastic is made from amber; fossilised tree resin and latex; a form of rubber.

The two main plastics are Natural plastics and syntheic plastics. Synthetic plastic is made from carbon based material; crude oil, coal, natural gas etc.

The two main TYPES of plastics are Thermosetting and thermoplastic. Thermosetting plastics cannot be reshaped wheras thermoplastic can be reshaped.

When choosing a plastic consider its; colour, texure, workability, structural,strength, type of plastic, can it be recycled etc.

Thermosetting Plastic-

Melamine Formaldehyde (methanol, MF: table-wear, electrical insallations, synthetic resin paints, decorative laminaes, worktops.

 Exposy resin (expoxide ER): Castings, printed circuit boards (PCBs), surface coating, Araldite glue.

Polyster resin (PR): Laminated to form glass reinforced plastic (GRP) castings, encapsulations: car bodies, boat.

Phenol Formaldehyde- Dark coloured electrical fittings and patrs for domestic apliances; kettle, iron, saucepan, handles

  Urea formaldyhde.- Doors and cupboard handles, electrical switch, electrical fittings

Polythene (High Density) (HDPE)- Pipes and bowls, milk crates, buckets

Polythene (Low Density) (LDPE)- Packaging, film, carrier bags, toys, 'squeezy' detergent bottles.

Polypropylene (PP)- Bottles, crates and boxes, Medical equipment and syringes, food containers, nets, storage

High Impact Polystryene (HIPS)-  Vacuum forming, electronic casing/ packaging

Nylon (Polyamaide)- Curtain rail fittings, combs, hinges, bearings, clohes, gear wheels

Rigid PVC (Polyvinyl Chloride)- Air and Water pipes, chemical tanks, shoe soles, shrink and blister packaging, floor and wall coverings

Acrylic (Polymethyl-Methacrylate)- Display signs, baths, roof lights, machine guard.

Line benderr-

They are moulded by a ***** heater or line bender.

The plastic sheet is heated along the line of intended fold

The softened area is then bent to shape using a bending jid for accuracy.

Vacuum Forming-

Heat plastic is sucked onto the former which forms the required shape.

A former can be a wooden mould around which the softened plastic will be held by the vacuum until it has cooled

Yoke Moulding

Oven set to 110 degrees celsius  to soften material

The peasure from a close fittting yoke will hold the platic until hardened.