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Technical aspects of designing and making. 2 nd Part of A565 Theory. What topics are covered in the exam?. Designing & Product Planning Materials Tools, Equipment & Processes Computer Applications Industrial Production Health & Safety Quality Product Evaluation. Theory Questions….
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Technical aspects of designing and making 2nd Part of A565 Theory
What topics are covered in the exam? • Designing & Product Planning • Materials • Tools, Equipment & Processes • Computer Applications • Industrial Production • Health & Safety • Quality • Product Evaluation
Theory Questions… What are the main stages of the design process? Explain the differences between the 4 different types of strength What is the main difference between softwoods and hardwoods? Name 4 good things about MDF Why would you put a finish on wood? What is the main difference between the 2 different types of plastic?
Designing & Production Planning • Identification of a design need • Analysing a design brief • Research, data and analysis • Identification of complex associations linking principles of good design and technological knowledge • Developing a design specification • Generating ideas and communicating design • Modelling and trialing techniques • Digital media and new technologies • Production planning • Material selection • Make product • Critical evaluation skills
Material Properties Performance characteristics of different materials have to be considered when choosing what products should be made of, you need to know the definitions of the following properties; • Hardness – resist cutting and indentations • Toughness – withstand shocks such as hammering • Strength = 4 types include the ability to withstand... • Being pulled apart or stretched • Crushed or compressed • Twisted • Sheared as a result of sideways force like scissors • Elasticity – can be stretched and then return to original length • Flexibility – bend but not break and return to original shape • Ductility – can be stretched into wire • Durable – can withstand bad weather conditions • Malleability – can be hammered, pressed into a shape
Materials - Hardwoods These come from ‘deciduous’ trees which shed their leaves in autumn. They are generally hard, tough, and durable and are reasonably expensive because they take longer to grow than softwoods.
Materials - Softwoods • Softwoods come from coniferous trees that remain evergreen all year round • Pine is the most common type; • grown mainly in Northern Europe it is easy to work, knotty, durable, widely available and cheap • It is most commonly used for construction work and cheap furniture
Materials – Manufactured boards • These are wood-based materials that are made by compressing and bonding thin sheets of wood (plywood) or particles (chipboard or MDF) together with adhesive. • Advantages over solid woods; • More stable as they don’t have grain • Available in large sheet sizes • Easier to buy from DIY shops • Less expensive THEY DON’T GROW ON TREES!!
Materials - Plastics There are 2 ‘families’ of plastics; Key Terms; • THERMOPLASTICS = such as acrylic, can be heated to make them soft so they can be shaped, this can be repeated many times. • PLASTIC MEMORY = is the ability of thermoplastics to return to their original state after reheating • THERMOSETTING PLASTICS = such as epoxy resin, can also be heated to make them soft so they can be shaped, but this can only be done once. They are particularly useful for making plastic products that are resistant to heat • DYES = can be added to plastics to make them a specific colour all the way through unlike woods or metals that can only be coloured on their surface.
Theory Questions… What is the main difference between softwoods and hardwoods? Name 4 good things about MDF Why would you put a finish on wood? What is the main difference between the 2 different types of plastic? What are the 2 parts of Araldite glue (epoxy resin)? What are the 2 main types of metals? What are the differences between them? What is the main difference between an alloy and an element? What is ‘work hardening’? And what is the heat treatment method that you can use to remedy it? Name 3 finishes that can be used to stop mild steel from rusting.
Materials - Metals Key Terms; • FERROUS metals contain iron, like steel – they rust and are magnetic • NON-FERROUS metals don’t contain iron, like aluminium and copper – they don’t rust and aren’t usually magnetic IRON ALLOYS are made from mixtures of different elements PURE METALS are made from one single element
Heat Treatment of Metals Key Point – The properties of some metals can be altered to suit particular applications by the use of heat treatment, which involves heating and cooling the metal in a carefully controlled way. • Hardening – make steel much harder but can be brittle. Do this by heating until cherry red and then quenched in oil. • Tempering – make steel that has been hardened more tough. Do this by heating to certain temperature (between 230ºC – 300ºC) and then quench in oil. • Case hardening – make outer surface of steel very hard. Do this by heating to cherry red, dipping in carbon powder, quench in water. • Annealing – Relieve problems caused by work hardening (when you hit/bend a metal it can become fragile and brittle). Do this by heating it to a certain temperature (depending on type of metal) and then allowing it to cool as slowly as possible.
Theory Questions… What are the 2 parts of Araldite glue (epoxy resin)? What are the 2 main types of metals? What are the differences between them? What is the main difference between an alloy and an element? What is ‘work hardening’? And what is the heat treatment method that you can use to remedy it? Name 3 finishes that can be used to stop mild steel from rusting. What type of material is an SMA? What does it do? What is an LCA? Why are they important? ‘Knobs’, ‘screws’ and ‘nuts’ are all funny words but what are they all types of? In RM what does the word ‘wasting’ mean? What tool is used to make wood and metal components with cylindrical cross sections?
Environmental & Sustainability Issues You need to know about; • Selection of materials based on a consideration of the environment and sustainability • The application of the 6Rs: Reduce, Reuse, Rethink, Refuse, Repair and Recycle. • ‘Life Cycle Analysis’ (LCA). • ‘Design for disassembly’ and the importance of recovering parts and materials from end-of-life products.
Design Issues – Making products easy and safe for humans to use • Anthropometrics • “The measurement of humans”
Design Issues – Making products easy and safe for humans to use • Ergonomics • Using anthropometric data to design products so they are easier and more comfortable for humans to use
How is ergonomics involved in the Design Process? Product Designer Anthropometric Data Basic Product Ergonomically designed chair
Tools & Processes - WOOD MARKING OUT
Tools & Processes - WOOD WASTING (CUTTING & SHAPING)
Tools & Processes - WOOD WASTING (CUTTING & SHAPING)
Tools & Processes - WOOD WASTING (CUTTING & SHAPING)
Tools & Processes - WOOD WASTING (CUTTING & SHAPING)
Tools & Processes - WOOD WASTING (CUTTING & SHAPING)
Tools & Processes - METAL MARKING OUT
Tools & Processes - METAL WASTING (CUTTING & SHAPING)
Tools & Processes – METAL & PLASTIC WASTING & SHAPING
Theory Questions… • What type of material is an SMA? What does it do? • What is an LCA? Why are they important? • ‘Knobs’, ‘screws’ and ‘nuts’ are all funny words but what are they all types of? • In RM what does the word ‘wasting’ mean? • What tool is used to make wood and metal components with cylindrical cross sections? • Which is the simplest wood joint? Why is this weaker than a hidden-dowel joint? Why are mitre joints sometimes used? • Why are injection moulding machines used in industry? • What is the main difference between soldering/brazing and welding? • Explain 5 reasons for why CAD is so good • Explain 3 reasons for why CAM is so good
FIXING – WOOD JOINTS If you’re keen then check out these other joints – they might ask you to name them (only 1-2 marks)