Engineering Craft Practice and Workshop Technology
What this domain tests
The Craft Practice and Workshop Technology domain checks whether a craftsman can plan a workshop job, select hand and machine tools, measure and mark out work, hold tolerances, and leave the workplace safe. COREN expects craft-level judgement: the right method, the right tool, and a traceable check-not just a finished part.
Core rules
- Work from a drawing and a job plan: material, operations, tools, inspection points and safety controls.
- Datum first. Mark out from a single datum and transfer dimensions; avoid cumulative marking errors.
- Measurement must match tolerance. A steel rule is not acceptable for a ±0.05 mm fit; use a vernier or micrometer.
- Fits: clearance = hole size − shaft size. A positive minimum clearance is a clearance fit; a negative value indicates interference.
- Machine guards stay in place. Isolation and lock-off precede blade, belt or chuck changes.
- Keep benches, walkways and machine surrounds clear; remove swarf with a brush or hook, never bare hands.
Worked example
An M10 × 1.5 internal thread is required in a mild-steel plate. Tap drill size ≈ major diameter − pitch = 10 − 1.5 = 8.5 mm. Select an 8.5 mm drill, centre-drill, drill through, chamfer, then use taper, second and plug taps in sequence with cutting lubricant. Check with the matching screw: it should enter freely without wobble. If the drill is 8.0 mm, the thread may bind or the tap may break; if 9.0 mm, the thread is weak.
Traps
Using a rule where a vernier is needed; marking from a rough edge; tapping dry; measuring a hot part; and treating a near-enough fit as acceptable. Exam questions often hide the datum or ask for the safety step before the machining step.