🔧 Year 7 Design & Technology

The Design Process

Design is a systematic process of identifying a problem, developing solutions, making a product, and evaluating it. Good designers follow a clear process.

The Design Cycle

• 1. Identify the problem: understand what needs to be solved. Who is it for? What are the constraints?
• 2. Research: look at existing products, interview users, collect data
• 3. Specification: a written list of criteria the product must meet (e.g. dimensions, materials, cost, user needs)
• 4. Initial ideas: generate a range of ideas (sketches, mind maps). Quantity before quality at this stage
• 5. Development: choose and develop the best idea; make models and prototypes to test it
• 6. Planning and making: plan the manufacturing process step by step, then make the final product
• 7. Evaluate: test the product against the specification; identify improvements

Design Brief

• A written description of the design task — what needs to be designed and for whom
• Sets the context and constraints (budget, materials, time)
• e.g. "Design and make a small storage box for a child's desk, using wood, that can hold pens and be decorated attractively"

ACCESS FM — Product Analysis

• Aesthetics — how does it look, feel, smell, sound?
• Cost — how much does it cost to buy and manufacture?
• Customer / Client — who is it for?
• Environment — how is it disposed of? What is its environmental impact?
• Size — what are its dimensions?
• Safety — is it safe to use?
• Function — what does it do? Does it work well?
• Materials — what is it made from? Why?

Drawing Techniques

Types of Drawing

• Freehand sketching: quick, rough drawings to generate ideas. Use loose lines and annotations to explain your thinking.
• Isometric drawing: a 3D drawing technique using a 30° grid. All vertical edges remain vertical; horizontal edges are drawn at 30° to the horizontal. Useful for block shapes.
• Orthographic/working drawing: shows an object from three views: front, side (end view), and plan (top view). Drawn accurately to scale. Used by manufacturers.
• Perspective drawing: one-point or two-point perspective creates a realistic 3D appearance (see Art section for details)

Annotation

• Annotating means adding written notes to your drawings to explain materials, sizes, features, and construction details
• Use leader lines (arrows) to point from the annotation to the relevant part
• Good annotations explain WHY, not just what: "Rounded corners — safer for a child; no sharp edges"

Modelling

• 3D models help test ideas before committing to the final material
• Card/foam models: quick and cheap; test proportion and form
• CAD (Computer-Aided Design): software to create precise digital models (e.g. Tinkercad, Fusion 360)
• 3D printing: turns a CAD model into a physical object layer by layer

Materials & Properties

Types of Wood

• Hardwoods: from broad-leaved trees (slow-growing); denser and harder. e.g. oak (strong, durable — furniture), balsa (very light — model making), mahogany, teak, walnut
• Softwoods: from coniferous trees (fast-growing, cheaper); generally softer. e.g. pine (construction, furniture), spruce, cedar, redwood
• Manufactured boards: made from wood fibres or veneers. Plywood (layers glued at 90°, very strong), MDF (medium density fibreboard, smooth, easy to cut and paint), chipboard (cheap, not very strong)

Metals

• Ferrous metals (contain iron): mild steel (most common, strong but rusts), stainless steel (rust-resistant, used in cutlery and surgical equipment), cast iron
• Non-ferrous metals (no iron): aluminium (lightweight, resists corrosion — aircraft, drinks cans), copper (excellent conductor — wires and pipes), brass (copper + zinc, decorative and durable)
• Alloys: mixtures of metals. Steel = iron + carbon; brass = copper + zinc; bronze = copper + tin

Plastics (Polymers)

• Thermoplastics: soften when heated and can be reshaped. e.g. acrylic (rigid, colourful, used in signs and displays), polyethylene (PE, used in bottles and bags), PVC (pipes and window frames), nylon (tough, flexible, used in gears and clothing)
• Thermosetting plastics: permanently set when formed; cannot be remoulded. e.g. melamine (heat-resistant work surfaces), epoxy resin, urea formaldehyde (electrical fittings)

Material Properties

• Strength: ability to resist forces (tensile, compressive, shear)
• Hardness: resistance to scratching and indentation
• Flexibility/elasticity: ability to bend without breaking and return to shape
• Ductility: ability to be stretched into wire (e.g. copper)
• Malleability: ability to be pressed into sheets (e.g. aluminium foil)
• Conductivity: ability to conduct heat or electricity
• Density: mass per unit volume; determines how heavy a material feels

Food Technology

The Eatwell Guide

• The UK government's guidance on proportions of each food group in a healthy diet
• Fruit and vegetables: approximately ⅓ of diet; at least 5 portions a day; vitamins, minerals, fibre
• Starchy carbohydrates: approximately ⅓; bread, rice, pasta, potatoes; energy source
• Protein: beans, pulses, fish, eggs, meat; builds and repairs body tissues
• Dairy and alternatives: milk, cheese, yogurt; calcium for bones and teeth
• Oils and spreads: small amounts of unsaturated fats; olive oil, sunflower oil
• High in fat, salt, and sugar: eat in small amounts

Nutrients

• Carbohydrates: main energy source. Simple (sugars) or complex (starch and fibre)
• Proteins: made of amino acids; needed for growth, repair, enzymes, hormones. Sources: meat, fish, eggs, beans, nuts
• Fats: concentrated energy store; needed for fat-soluble vitamins and insulation. Saturated (animal fats — linked to heart disease) vs unsaturated (plant and fish oils — healthier)
• Vitamins: needed in small amounts for body processes. Vitamin C (immune system, citrus fruits), Vitamin D (calcium absorption, sunlight/oily fish), B vitamins (energy release)
• Minerals: calcium (bones/teeth — dairy), iron (red blood cells — red meat, spinach), sodium (fluid balance — salt; too much raises blood pressure)
• Water: 60–70% of the body; needed for all chemical reactions; should drink 6–8 glasses per day
• Fibre (NSP): aids digestion; found in wholegrain foods, fruit, vegetables, pulses

Food Safety

• Bacteria multiply in the danger zone: 8°C – 63°C. Keep food above 63°C or below 8°C.
• The 4 Cs of food safety: Cleaning, Cooking, Chilling, Cross-contamination (prevention)
• Cross-contamination: transferring bacteria from raw food to cooked food. Prevent by using separate chopping boards (colour-coded: red for raw meat, green for vegetables)
• Core temperature for cooked meat: 75°C for 2 minutes or equivalent
• High-risk foods (those that bacteria love): cooked rice, cooked meat, eggs, dairy, shellfish

Tools & Workshop Safety

Common Hand Tools

• Marking tools: ruler, try square (checking right angles), marking gauge (parallel lines), scriber (marking metal), pencil/chinagraph pencil
• Saws: tenon saw (precise straight cuts in wood), junior hacksaw (cutting thin metal/plastic), coping saw (curved cuts)
• Files and rasps: remove material and smooth surfaces. Double-cut file (roughing), single-cut (finishing)
• Chisels: remove waste wood; always cut away from yourself; use a mallet
• Planes: smooth wood surfaces; the jack plane and smoothing plane are most common
• Drills: hand drill (brace and bit), electric drill; always clamp the workpiece

Workshop Safety Rules

• Always walk, never run in the workshop
• Tie back long hair and secure loose clothing before using machinery
• Always clamp your work securely before cutting
• Use the correct tool for the job; never use a blunt tool (more likely to slip)
• Always cut away from your body and keep fingers away from the blade path
• Know where the emergency stop buttons are
• Never use machinery without teacher supervision
• Report any accidents or near-misses immediately
• Return tools to their correct storage place after use

Electronics Basics

Key Components

• Battery / power supply: provides the electrical energy. Measured in volts (V)
• LED (Light Emitting Diode): a component that emits light when current flows through it; must be connected the right way round (longer leg = anode/positive)
• Resistor: limits current flow to protect other components. Resistance measured in ohms (Ω). Colour-coded bands show resistance value.
• Switch: opens or closes a circuit. Types: push-to-make (momentary), toggle, slider
• Buzzer: produces sound when current flows
• Motor: converts electrical energy to rotational motion
• LDR (Light Dependent Resistor): resistance decreases as light increases. Used in automatic lights
• Thermistor: resistance changes with temperature. Used in thermostats

Circuit Basics

• A complete circuit is needed for current to flow: power source → components → back to power source
• Series circuit: components connected in a single loop. If one breaks, all stop working
• Parallel circuit: components connected in separate branches. If one breaks, others still work
• Ohm's Law: V = I × R (Voltage = Current × Resistance)
• Schematic (circuit) diagram: uses standard symbols to represent components

Microcontrollers

• A microcontroller is a small computer on a chip that can be programmed to control electronic systems
• Popular beginner options: Arduino, BBC micro:bit, Raspberry Pi Pico
• Inputs (sensors) give the microcontroller information; outputs (LEDs, buzzers, motors) respond to the program
• Programmed using block-based languages (Scratch, MakeCode) or text-based (Python, C++)