BGCSE Design & Technology common mistakes
BGCSE Design & Technology · Understand the traps and how to avoid them.
Jumping straight to a final design sketch without recording any investigation, brief, or specification, so the coursework folder opens with a drawing and no stated problem.
Candidates see the finished product as the 'real work' and treat written analysis as padding, often because earlier projects were marked mainly on the artefact.
What to do instead
Use a fixed one-page-per-stage template (investigation, brief, specification, ideas, development, plan, make, evaluate) and refuse to start the ideas page until the brief and at least five measurable specification points are written; each specification point must be testable (a dimension, a load, a cost, a material property).
Producing a single idea and labelling it 'final design', with no alternative concepts and no evidence of development such as annotation, dimension changes, or material substitution.
Time pressure near deadlines and a habit of drawing only when the idea is already settled in the candidate's head.
What to do instead
Draw three genuinely different concepts at thumbnail size first, compare them in a short table against the specification, then develop the chosen one through at least two annotated iterations showing what changed and why.
Choosing materials by colour or familiarity rather than by property, e.g. specifying mild steel for a garden bench seat or acrylic for a hot-drink coaster, without justification.
Property terminology (hardness, toughness, ductility, thermal conductivity, moisture movement) is learned as vocabulary but not linked to selection decisions.
What to do instead
For every material choice, write one sentence naming the service condition and the property that satisfies it, and keep a comparison table of the three or four candidate materials with the deciding property highlighted.
Confusing the names and functions of similar hand tools, for example describing a try square as a measuring tool that gives a dimension, or a tenon saw as the tool for cutting curves.
Tools are often learned from labelled diagrams without handling them, so shape is remembered but purpose is not.
What to do instead
Learn each tool as a three-part card: name, the job it does, and the one thing it does that no other tool on the list does (try square marks and checks squareness but does not measure length; coping saw cuts curves; tenon saw cuts straight joints to depth).
Describing a workshop safety rule in the abstract ('always be careful') instead of naming the specific hazard, the control, and the protective equipment for a named process.
Safety questions invite generic answers, and candidates have not practised the hazard-control sentence pattern.
What to do instead
Answer every safety question with a three-part sentence: hazard (e.g. airborne dust when sanding), control (extraction or damping the surface), and personal protection (eye protection and a dust mask); practise this on five named processes including drilling, soldering, and hand sanding.
Writing process descriptions as lists of machine names with no sequence, parameters, or quality checks, e.g. 'use the lathe, then finish it' for a turned component.
Candidates remember equipment but not the ordered operations or the settings that make the result correct.
What to do instead
Write each process as numbered operations with at least one setting or parameter per step (speed, feed, depth of cut, cure time, clamping method) and one inspection point; rehearse by writing the full sequence for a drilled and countersunk hole.
Producing third-angle and first-angle orthographic views mixed on one drawing, or placing the plan above the front view when the convention requires it below.
The two systems look identical for a single view, so the difference is only exposed when a second view is added, and candidates copy whichever layout they last saw.
What to do instead
Before drawing, write 'third angle' or 'first angle' in the title block and apply the rule: in third angle the view is placed on the side from which it is seen; in first angle it is placed on the opposite side. Check by confirming the plan sits below the front view in first angle and above it in third angle.
Explaining a mechanism by naming it only ('it is a lever' or 'it uses a pulley') without identifying the effort, load, pivot, or the resulting mechanical advantage.
Mechanism names are easy to recall, but the force analysis requires a free-body sketch that candidates skip under time pressure.
What to do instead
For every mechanism answer, sketch the layout, label effort, load and pivot or fulcrum, state the class or type, and calculate mechanical advantage as effort arm divided by load arm (or the equivalent ratio for gears and pulleys) with units shown.
Treating a circuit as a list of components rather than a path, drawing a series circuit when parallel is required, or omitting the return path so the lamp cannot light.
Candidates draw component symbols from memory without tracing the current from the source and back.
What to do instead
Trace the path with a finger from the positive terminal through every component to the negative terminal before labelling anything, and state in words why series or parallel is chosen (parallel keeps independent switching and equal voltage across branches).
Discussing sustainability only as 'it is recyclable' or 'it is bad for the environment', with no reference to material source, energy in manufacture, product life, or end-of-life route.
Sustainability is treated as a moral add-on rather than a set of measurable decisions, and candidates lack a checklist to structure the answer.
What to do instead
Answer with a six-point lifecycle checklist: material source (virgin or recycled), energy used in production, expected product life and repairability, transport distance, disassembly for repair or recycling, and disposal route; apply the same checklist to the product being evaluated in the coursework.