Presentation on theme: "GCSE Resistant Materials Techniques and Processes Summer Examination 2011."— Presentation transcript:
GCSE Resistant Materials Techniques and Processes Summer Examination 2011
Wood Joints Wood can be joined together in several ways. There are a number of different joints that can be used for a number of different purposes. Wood joints are often glued also to make them stronger and more secure. Butt joint – weaker joint, but quick and simple to produce. Used to produce cheap furniture. Mitred joint – similar to a butt joint but more aesthetic. They are more difficult to cut because of the angle and will have a larger gluing area. Used to produce picture frames, door frames etc. Lap joints have a larger surface area for gluing than a butt joint which makes them stronger. Used to create drawers and boxes.
Wood Joints Dowel joints use a wooden or plastic peg called a dowel, which fits into aligned holes to reinforce the joint. They are often used in factory produced furniture. Mortise and Tenon joints are really strong and are often used to produce tables and chairs. Halving joints are fairly strong and have a large surface area for gluing. This type of joint is used to create frames, and frame construction. Housing joint – this type of joint it used in shelving units, they have a good surface area for gluing, and provides support along the length of the joint. Dovetail/finger (comb) joints are attractive and strong joints, used often in drawers and furniture, but are harder to create.
Joining Metals The most common way of joining metals to metals involves using heat. Soft Soldering This is a quick method of joining copper, brass and tinplate when a little strength is required. It is also used for joining components to a circuit. The filler rod/solder melts at relatively low heat with a mixture of tin, silver and copper. Hard soldering Also known as silver soldering, uses a filler rod like soft soldering but melts at higher temperatures. Brazing is used for joining mild steel, instead of a soldering iron a brazing torch is used. Welding Welding is much stronger for joining metals and required 2500 degrees heat. The heat helps to melt the metal and a filler rod is used to help fuse the two materials together.
Quantity Production Quantity production Depending on demand, products are made using a range of quantities, from large scale or ‘mass’ production (screws, light bulbs) to a one off product (bespoke items). There are advantages and disadvantages to this. Level of Production DescriptionExamples One Off production A product designed and manufactured for a specific situation, more often hand made products. A sculpture, coursework Batch productionMachinery is used to manufacture a series of products, jigs or formers may be used. Table, stools Mass productionA product goes through various stages of manufacture, with specialist workers producing high volumes. Cars, Light bulbs nuts, screws Continuous production Food, oil and steel are examples of products that are continually in production. Food items, petrol, computer chips
Quantity Production Jigs: a jig is an aid to fast, accurate and repeatable manufacture. There are a few types of jigs that can be sued in production. Drilling jig: when drilling a whole in identical components a drilling jig saves time and increases accuracy. The number of repeated operations depends on the material the jig is made from, for smaller projects MDF or Mild steel are adequate but for multiple uses hardened steel may be used. Bending Jig: a bending jig is used to help bend or form material. They are used to improve accuracy and efficiency, and they cause no damage to the material being shaped. Wood is often used for making this type of jig. Templates: templates are meant to be simple and easy to use. Often these are made from paper and card, but for repetitive use more durable materials may be beneficial. Templates should save time by not needing to repeatedly mark out. Vacuum forming moulds: these are often made from wood, card or clay, these are resistant to low level heat. More complicated shapes can be created but a tapered edge would be needed to allow the material to be removed from the mould. Vacuum forming moulds can be used several times if made from a robust material.