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WHAT ARE HARDWOODS ? Sometimes called broad-leaf trees. Lose their leaves seasonally, in winter. Hardwoods tend to be harder than softwoods (with the exception of Balsa Wood). They have a wider variety of colour and texture than softwoods. Hard woods tend to be more expensive than softwoods and take longer to mature.		HARDWOODS 1 EUROPEAN OAK Light tan in colour and straight grained. High quality timber. Moderately hard to work with handtools. Tools should be kept sharp. Produces a high quality finish with wax, furniture oil and varnish. Uses include; quality furniture, cabinet making and boat building.
HARDWOODS 2 EUROPEAN WALNUT Grey to brown colour with relatively straight grain. Excellent timber. Tough and can be worked reasonably easily with hand tools. Easy to carve and can be smoothed to a highly polished finish. Used in solid and veneer form for high-class furniture, cabinet making, bank and office fittings.		HARDWOODS 3 BALSA Unlike most hardwoods. Fast growing. Reaches maturity in just five to seven years. Very soft and easy to work with tools. Pale in colour and extremely light to carry/transport. Extremely popular as a material for model making. Also used occasionally to package delicate items.
HARDWOODS 4 EUROPEAN ASH Colour - cream to pale tan. Tough, flexible and straight grained, very good steam bending qualities. Can be shaped and formed well with handtools. A smooth finish can be achieved and stains well. Used for cabinet making, boats and handles of tools. Ash veneered plywood is popular.		HARDWOODS 5 BRAZILIAN MAHOGANY Medium to dark brown in colour. Relatively easy to work with hand tools and machinery. Produces a good quality finish with glass paper. Takes varnish well. Wide range of uses including furniture and boat building. Used widely as veneer.
HARDWOODS 6 ENGLISH ELM  Light brown / pale brown in colour. Can be difficult to work with handtools, due to awkward grain. Can be worked to a fine finish. Looks particularly good with a waxed finish. Used in cabinet making, turns quite well and is used as veneer, to provide a quality finish on cheaper woods.		HARDWOODS 7 EUROPEAN BEECH  Pale white to pink brown in colour. Very good for steam bending. It can be worked reasonably well with handtools and machinery. Used for quality furniture, handles, manufacturing chairs and good for wood turning. Often used as a facing for plywood.

WHAT ARE SOFTWOODS ? Softwoods are from trees that have needles / exposed seeds, not leaves. They grow quickly, compared to most hardwoods. When sawn and planed they tend to be light/pale in colour. Softwoods also tend to be cheaper than hardwoods. Softwoods are used by the construction industry and are use to produce paper pulp, and card products.		SOFTWOODS 1 - PARANA PINEVirtually knot free with straight grain, making it ideal for a range of uses. Light brown. Very easy to cut and shape, meaning accurate work is easier to achieve than with most softwoods and hardwoods. A smooth finish can be achieved. Used in the manufacture of furniture. Often used for turning wood products. Used to manufacture plywood.
SOFTWOODS 2 - SCOTS PINE Sometimes called Red Deal. A popular natural wood. Can be resinous and have plenty of knots. Coloured from light yellow to dark brown. Can be shaped and formed reasonably easily by handtools and machines. Often used for furniture and the construction industry. Used for interior work. One of the most commonly used woods.		SOFTWOODS 3 - RED CEDAR Has a pleasant aroma, when cut and machined. Its straight grain means that it works well with tools and machines. Starts as reddish brown in colour, after weathering turns to a silver grey. Used for decking, furniture and general construction. Used for roof shingles, due to its resistance to all weathers.
SOFTWOODS 4 - YEW Straight grained which means it can be shaped and formed quite easily. However, the grain can sometimes be difficult to work. An oily wood that resists natural degradation from the weather and elements.. Used to manufacture both interior and exterior furniture e.g. chairs, gate posts and wood turning.		SOFTWOODS 5 - DOUGLAS FIR A reddish brown wood and relatively knot free. Good to work with handtools and machinery. When smoothed to a fine finish, the grain tends to standout from the surface. Used extensively in the construction industry and in the production of plywood. Also used in a range of joinery work.
SOFTWOODS 6 - SEQUOIA A reddish to brown wood with a texture that varies from smooth to coarse. Can be worked quite easily with handtools and machines. Glass paper produces a good, smooth finish. Used regularly as roof shingles, due to its resistance to the weather. Used for interior and exterior joinery.		SOFTWOODS 7 - LARCHHigh in resin and straight grained. Pale red to brick red. Can be worked reasonably well with handtools, if knots are avoided. It is a tough softwood and has a range of uses including; boat planking, window frames, floors and staircases.

HAT ARE THERMOSETTING PLASTICS ? Once heated and moulded, these plastics cannot be reheated and remoulded. The molecules of these plastics are cross linked in three dimensions and this is why they cannot be reshaped or recycled. The bond between the molecules is very strong.		THERMOSETTING PLASTICS 1 Many adhesives (glues) are thermosetting plastics. For example, Araldite. Composed of two tubes (one is resin, the other a catalyst). They are mixed to form the glue.
THERMOSETTING PLASTICS 2 Polyurethane. This forms the basis of many paints and varnishes. Tough, water resistant.		THERMOSETTING PLASTICS 3 Melamine Formaldehyde. Because of its smooth surface and hygienic qualities, used for kitchen laminates surfaces. Also used for electrical plugs and sockets, because it can be cast and it is an excellent insulator.
THERMOSETTING PLASTICS 4 Urea Formaldehyde has physical properties of high hardness and high toughness, making it suitable for strong, knock-resistant electrical fittings. It is also scratch resistant and a very good electrical insulator. Electrical fittings manufactured from this polymer are safe to use.		THERMOSETTING PLASTICS 5 Polyester resins. If resins are combined with a material such as fibre glass, the result is a very tough material that can resist impact. Known as Glass Reinforced Plastic (GRP) and is used in car body repairs, sailing boats and corrugated sheet, because of its lightness, toughness and resistance to water.
THE DIFFERENCE BETWEEN  THERMOSETTING PLASTICS  AND THERMOPLASTICSThermosetting plastics once heated and formed to a shape,cannot be reheated and reformed. Consequently, they tend to be difficult to recycle. Thermoplastics once heated and formed to a shape, can be reheated and reshaped. Every time they are reshaped, the quality of the thermoplastic tends to be reduced. They are recyclable.

HAT ARE THERMOPLASTICS ? These plastics can be re-heated and re-shaped in various ways. They become mouldable after reheating as they do not undergo significant chemical change. Reheating and shaping can be repeated. The bond between the molecules is weak and becomes weaker when reheated, allowing reshaping. These types of plastics can be recycled.		THERMOPLASTICS 1 Acrylic. (Known also as PERSPEX) This is the most common plastic in a school workshop. Purchased 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. Easy to cut shape. Polishes well. Baths, safety glasses, signs.
THERMOPLASTICS 2 LDPE - Low Density Polythene is tough and flexible. Softer than HDPE. Can be moulded into almost any form. Flexible, comes in range of colours. Bottles and plastic bags are made from the low density polystyrene.		THERMOPLASTICS 3 HDPE - High Density Polythene which is rigid and hard. Less flexible than LDPE. Machine parts, bowls and crates are generally made from high density polystyrene. Can be moulded into almost any form. Flexible, comes in range of colours.
THERMOPLASTICS 4 Polypropylene (PP) is a thermoplastic often formed into products through injection and blow moulding. It is robust, strong, flexible and supplied in a range of colours. Food containers, chairs, packaging and storage units.		THERMOPLASTICS 5 Polyvinyl Chloride. Better known as PVC. A tough material, purchased as either a hard (inflexible) material or alternatively a flexible form. It can be extruded, welded or bonded with an adhesive. Range of uses including water pipes, raincoats, long play records, coating on electrical wires and packaging.
THERMOPLASTICS 6 Nylon. Is used in engineering to make gears and bearings. It’s oily nature means that friction is reduced between moving parts made from nylon. Gears, bearings, wheels and clothing.		THERMOPLASTICS 7 High Impact Polystyrene (HIPS). Light material and yet strong. Available in a range of colours. Can be vacuum formed. Thinner HIPS is quite flexible. Used for electrical casings, packaging, trays

FERROUS METALS - IRON Wrought Iron was used by the Romans. Roman iron weapons were forged, not cast. Iron was forged by heating it to high temperatures (to red heat) and hammering it into shape. Britain had numerous Roman iron ore mines. It also had large forests, which provided the wood required for smelting (extracting the iron form the ore).		FERROUS METALS - IRON -  INDUSTRIAL REVOLOUTION Abraham Darby 1st (1678 –1717) Developed a technique of producing ‘pig iron’ in large quantities, through casting molten iron, crucial to the industrial revolution. He developed sand casting techniques, making it possible to produce cast products of a high standard.
FERROUS METALS PROPERTIES OF IRON Cast iron has a carbon content higher than 2.1%. Cast iron is brittle and can snap. Cast iron is likely to break/shatter if dropped or when it receives a ‘blow’. Products include; cast iron garden furniture, house numbers, weathervanes and vices.		METALS- WHAT IS AN ALLOY? An alloy is a metal (parent metal) combined with other substances (alloying agents), resulting in superior properties such as; strength, hardness, durability, ductility, tensile strength and toughness. The parent metal is the majority of the alloy. For example, mild steel is 0.1 - 0.3% Carbon and 99.9 - 99.7% Iron.
FERROUS METALS  THE ALLOY STEEL Iron is the most used metal in the world, largely due to it being the main constituent of the alloy steel. Common steel typically has 0.2 to 2.1% carbon content, with the rest being iron. Our modern world relies on steel		FERROUS METALS - MILD STEEL Carbon 0.1 - 0.3% Iron 99.9 - 99.7% Alloy of carbon and iron. Tough. High tensile strength. Can be case hardened. Rusts very easily, unless the surface is protected from moisture. Most common metal used in school workshops. Used in general metal products and engineering.
FERROUS METALS  CARBON STEEL Carbon 0.6 - 1.4% Iron 99.4 - 98.6% Alloy of iron and carbon. Higher carbon content than mild steel. Tough and strong. Carbon steel can be heat treated e.g. hardening and tempering. Used for cutting tools such as drills and lathe tools.		FERROUS METALS  STAINLESS STEEL Alloy of iron, nickel and 10.5% to 11% chromium. Tough, resistant to rust and stains. Does not corrode. Cutlery, medical instruments, specialist corrosion resistant products such as pipes. Stainless steel pots and bans. Jewellery and watches.

FERROUS  AND  NON-FERROUS METALS Ferrous metals contain IRON These are metals that contain iron. Consequently they tend to rust / suffer from corrosion. They need protecting with paint, oil or a surface finish. They react to a magnet. Non-ferrous metals do not contain IRON Non-ferrous metals do not contain iron. Consequently, they do not to rust or suffer unduly from contact with moisture. They do not react to a magnet.		NON-FERROUS METALS ALUMINIUM Light grey in colour. Smelted from bauxite ore. Aluminium 95%, Copper 4%, Manganese 1% Ductile, soft, malleable, machines well on lathes and milling machines. Very light and resists corrosion. Can be cast into products from ingots. Used widely in aircraft, drinks cans, window frames, ladders, and kitchen ware.
NON-FERROUS METALS  COPPER Reddish brown in colour, darkens slowly when in contact with air. This metal is not an alloy. Ductile, can be beaten into shape as it is relatively soft. Conducts electricity and heat. Electrical wiring, tubing, kettles, bowls, pipes and plumbing. Used also in the production of printed circuit boards.		NON-FERROUS METALS BRASS A copper alloy. Deep yellow to golden colour. An alloy, mixture of copper and zinc 65% - 35%. Casts and machines well. Surface tarnishes slowly on contact with air. Conducts electricity. Resists corrosion. Parts for electrical fittings, engineering, ornaments, musical instruments.
NON-FERROUS METALS BRONZE A copper / tin alloy. Tin content up to 10%. Engineers well on lathes and works quite well with handtools. Once used for ship fittings, due to its resistance to corrosion.  Now replaced by stainless steel. Used for ornaments, cast bronze sculptures and ships propellers. Used also for bearings in engineering.		NON-FERROUS METALS PEWTER Pewter is a soft, malleable alloy, 85% to 99% tin. Other metals are copper, lead, antimony and bismuth. Has a low melting point compared to many metals (170–230 °C) making it highly suitable for casting. Usually purchased in ingots and cast to shape in a workshop. Used for making tankards and other decorative pieces.

WHAT ARE COMPOSITE MATERIALS ? Composite materials, also called Composites. Composed of two or more materials, that have different properties. The materials are bonded together and their properties are combined. Composite materials combine the physical properties of the individual materials they are made up of, forming a superiormaterial. KEVLAR  -  REINFORCED CONCRETE PLYWOOD  -  GLASS REINFORCED FIBRE CARBON FIBRE		COMPOSITE MATERIALS - CONCRETE Used in construction, roads, brick laying, building and many more. Concrete is composed of a number of materials, that combine to form this versatile building material. Most concrete is made up of Portland Cement, aggregates (gravel, crushed stones) and sand. Water is added to the mix.
COMPOSITE MATERIALS -  STEEL REINFORCED CONCRETE Concrete is weak when put under tension. If reinforced with steel rods, it is can withstand tensile forces. Reinforced concrete has long steel rods passing through its length, adding great strength to the final composite material. Able to resist tensile forces. Used for bridge building, skyscrapers and general large scale construction.		COMPOSITE MATERIALS GLASS REINFORCED PLASTIC(GRP) Composed of strands of glass and woven to form a flexible fabric. Placed in a mould and polyester resin is added, followed by a catalyst (to speed up the reaction). Allowed to dry/cure. The resulting material is strong and light. Can be sanded and painted. Used for canoes, car bodies, small swimming pools, water tanks, surfboards, small boat hulls.
COMPOSITE MATERIALS CARBON FIBRE REINFORCED POLYMER (CFRP) Carbon fibre is woven into a textile material. Epoxy resin is added and allowed to cure. The resulting material is very strong and light. An improvement on glass fibre reinforced plastic, although much more expensive. Uses; Aerospace, expensive sports cars, competition bicycles and motorbikes.		COMPOSITE MATERIALS - KEVLAR Kevlar® is a liquid, converted into a fibre (called aramid fibres) and woven into a textile material. Extremely strong, lightweight, corrosion and heat resistant. Has a high tensile strength to weight ratio, far exceeding steel, carbon fibre and specialist alloys. Uses when combined with other materials: bullet proof jackets, armour for military vehicles and planes. Formula 1 fuel tanks. SMART MATERIALS - POLYMORPH Polymorph is a thermoplastic material that can be shaped and reshaped any number of times. Supplied as granules. Heated in hot water - at 62 degrees centigrade, the granules form a mass of ‘clear’ material that can be shaped into almost any form. On cooling it becomes as solid. Suitable for 3D modelling, as it can be shaped by hand or pressed into a shape through the use of a mould.   SMART MATERIALS SHAPE MEMORY ALLOY (SMA) SMA wire also called ‘Nitinol’, as it is a composed of nickel and titanium. Looks like ordinary wire and has many of the same properties. SMA has a memory - for example, if it is folded to form a shape and then heated above 90 degrees (centigrade) it returns to its original shape.       SMART MATERIALS SHAPE MEMORY ALLOY (SMA) SMA can be ‘programmed’ to remember a shape. Clamp the SMA in position and pass an electric current through it. If the wire is now folded into another shape and then placed in hot water, it returns to the original ‘programmed’ shape.   SMART MATERIALS THERMOCHROMIC INKS Thermochromic inks change colour in response to changes in temperature. These inks have serious applications such as in the food industry. They can be used to indicate when a packaged food has reached the correct temperature in an oven. They are also used in forehead thermometers.       SMART MATERIALS - HYDROCHROMIC INKS Hydrochromic inks are those that change colour when they make contact with water. A plastic moisture tester is pushed into the soil alongside the plant. If the water content of the soil is at the right level, the colour of the moisture tester should remain blue. However, if the soil becomes dry, the colour changes to yellow.   SMART MATERIALS - PHOTOCHROMIC INKS Photochromic ink darkens, as the light level increases. Some photochromic inks change colour. In fact, it is UV light that causes the darkening of the ink, which means the ink works best in natural light. This special ink has two main applications; sunglasses and spectacles.       SMART MATERIALS - AROMA PIGMENTS These are inks / paints that produce an aroma when scratched. They are popular in ‘scratch and sniff’ products, such as perfume samples etched into women’s magazines. The reader scratches the sample aroma pigment, releasing an aroma matching the selected perfume.   HYDROCARBON  - ENCAPSULATING POLYMERS Polymers that absorb oil, forming a rubbery substance. They are environmentally ‘friendly’, developed to manage hydrocarbon-based liquid spills. A potential practical application is at petrol / diesel fuel stations. If a spill at the pump takes place, a HC Polymer can be applied, absorbing the fuel, safely. It can then be used as a solid fuel and even burned. MODELLING MATERIALS - PLASTICINE Plasticine is a form of modelling clay. Although normally associated with children, this material is useful in the initial stages of design, when quick model making is important. It can be shaped / moulded by hand and reused. Plasticine comes in a range of colours.   ART STRAWS Art straws are ideal for making model structures . They are supplied in a range of colours, shapes and sizes and can be glued or taped together. A good example of a model made from art straws, is a model bridge.       COLOURED CARD Coloured card is supplied in a range of colours, shades and thicknesses. Card that has different colours on the front and back surfaces can even be bought. It is suitable for colourful models, especially the early stages of making a series of models. A good example of card as a modelling material, is in the manufacture of a prototype board game.   CORRUGATED CARD Corrugated card is quite thick and relatively strong. It is used for the manufacture of initial / rough models, as it can be cut and shaped easily and is relatively cheap. It can be salvaged from cardboard boxes and sellotaped together to form models.       CARD CLAD FOAM BOARD Foam boards are lightweight and easy to cut and shape. It is ideal for model making, although foam board can be relatively expensive. Card clad foam board is - foam with thick card applied to either surface. It can be cut and shaped easily, using hand tools and light equipment such as fretsaws.   BALSA WOOD Balsa wood is a traditional model making material. Ideal for model making. Although classified as a hardwood, it is very soft and easy to cut and shape. However, it is easily broken or snapped and therefore great care is needed when cutting and shaping. It can be painted with water based paints and even varnished.       STYROFOAM Styrofoam is an excellent model making material. It is very light and easy to cut and shape, using a hot wire cutter. It can also be shaped with hand tools and files. It can be painted using water based paints (emulsion paints) giving a really good finish. Using styrofoam requires patience, as it can ‘crumble’ at the edges if care is not taken.   PVC / HIGH DENSITY POLYSTYRENE High Density Polystyrene, also known as compressed polystyrene, is ideal for model making due to its physical properties. It can be cut and shaped quite easily with fretsaws and even hand tools. It is supplied in a range of colours, shades and thicknesses. This type of materials is used for vacuum forming, although it is suitable for model making.