Measuring and marking out
- Steel rules, try squares, scribers, odd-leg callipers and centre punches are used for marking out. Engineer's marking blue makes scribed lines easy to see on metal.
- Vernier callipers measure lengths, internal and external diameters and depths, often to 0.02 mm. Micrometers measure to 0.01 mm.
- A tolerance is the acceptable variation in a size. 50 ± 0.2 mm means any size from 49.8 mm to 50.2 mm is acceptable. Go/no-go gauges check sizes quickly.
Tools and equipment
- Hand tools: hacksaws, files, taps and dies, hand drills and soldering irons.
- Machines: pillar drills, centre lathes, milling machines, bandsaws, laser cutters and 3D printers.
- Choose the right tool, speed and cutting fluid for the material.
Health and safety
- Risk assessments identify hazards, who might be harmed, and control measures.
- PPE (personal protective equipment) includes goggles, aprons, welding masks and safety boots.
- Machines have guards and emergency stop buttons. COSHH regulations control hazardous substances, such as solvents. The Health and Safety at Work Act 1974 sets duties for employers and employees.
The NEA
- The NEA (non-exam assessment) is worth 60% of the GCSE; the written paper is worth 40%.
- Students respond to a brief set by AQA: analyse the brief, research, write a specification, develop designs with engineering drawings, plan production, make the product, test it and evaluate it against the specification.
- A production plan (such as a Gantt chart) sets out the order of tasks, tools, timings and quality checks.
Key terms
- Vernier callipers
- A measuring tool that measures to about 0.02 mm.
- Micrometer
- A precision measuring tool that measures to 0.01 mm.
- Tolerance
- The acceptable variation in a size.
- PPE
- Personal protective equipment.
- Risk assessment
- Identifying hazards and how to control them.
- COSHH
- Regulations controlling substances hazardous to health.
- Gantt chart
- A chart showing the order and timing of tasks.
- Specification
- A list of requirements a product must meet.
Practise Practical engineering skills and the NEA: 10 questions