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PINE - Is a relatively cheap wood used in the building trade and for furniture. It is pale in colour . SOFTWOOD. quite easy to cut and shape, and machines relatively well. HARDWOODS.
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PINE - Is a relatively cheap wood used in the building trade and for furniture. It is pale in colour SOFTWOOD quite easy to cut and shape, and machines relatively well. • HARDWOODS MAHOGANY - Is quite expensive and is used for good quality furniture and hardwood windows. It is light brown in colour and more difficult to use compared to pine. OAK - This is an expensive material and is used in for making quality, expensive furniture. Steel fittings such as hinges will stain oak so it is important to use brass ones.
MANMADE BOARDS BLOCKBOARD - This is built up with a core of softwood strips bonded together with adhesive and covered with a sheet of plywood on either side. Used as a building material and for furniture manufacture including fitted kitchens / bedrooms. HARDBOARD - This is made from wood fibres that have been pulped. The pulp is put under pressure until the fibres bond to produce a tough board that is smooth on one side and rough on the other. It is not as strong as the other boards. PLYWOOD - This is made from veneers (plies) of timber with each grain layer being at right angles to each other and bonded together by resin and pressure. A number of grades are available, designed to suit a variety of situations. MEDIUM DENSITY FIBRE BOARD(MDF) - A quality board, relatively cheap. This board is composed of fine wood dust and resin pressed into a board. This material can be worked, shaped and machined easily. Paint can be applied to it without the need for an undercoat or primer. Used in the building and furniture trades.
WHAT IS A SUSTAINABLE FOREST? A sustainable forest is a forest that is carefully managed so that as trees are felled they are replaced with seedlings that eventually grow into mature trees. This is a carefully and skilfully managed system. The forest is a working environment, producing wood products such as wood pulp for the paper / card industry and wood based materials for furniture manufacture and the construction industry. Great care is taken to ensure the safety of wildlife and to preserve the natural environment. Sustainable forests are the result of a commonsense policy to replace trees that are felled so that forests continue to exist providing natural materials for us all.
EXAMPLE THERMOPLASTICS Polyethylene. The most common plastic in everyday life. Used in the manufacture of 'plastic' bottles, grocery bags, shampoo bottles and children's toys. Acrylic. This is the most common plastic in a school workshop. It is purchased usually in the form of sheets and comes in a range of colours. It can be translucent (e.g. smoked), transparent or opaque. It is resistant to most acids and weather conditions.
EXAMPLE THERMOSETTING PLASTICS Polyester resins. If resins are combined with a material such as fibre glass the result is a very tough material that can resist impact. This type of material is known as a glass reinforced plastic (GRP) and is used in car body repairs, sailing boats, corrugated sheet because of its lightness, toughness and resistance to water. Melamine Formaldehyde. Used in the production of plastic laminates because of its smooth surface and hygienic qualities. It is also used in electrical plugs and sockets because it can be cast and it is an excellent insulator.
PlasticNot very environmentally friendly Oil refineries ‘refine’ oil in massive quantities, to produce the fuels we need. These include diesel, petrol and heating oil. However, some of the raw materials we need to manufacture plastics, are also extracted from oil at the refinery. When crude oil is refined, four percent ends up as raw materials for the production of plastics.
Metals FERROUS AND NON-FERROUS METALS Stainless steel Mild Steel Cast iron Wrought iron Copper Lead Aluminium Brass