Question 3
(a) Explain the following types of auto body construction.
(i) integral body construction;
(ii) composite body construction.
(b) (i) State one advantage of aluminium over steel, as used for auto body construction.
(ii) State one safety precaution observed when repairing aluminium panel.
(c) (i) State two welding defects which can be affect the welded portion of plastics.
(ii) Name one type of plastics resin.
Observation
The Candidates did well on this question number. However, some of the candidates could not satisfactorily answer the questions asked in 3(b).
The solution of the poorly answered part of the question is given below.
(b) (i) Advantages of Aluminium over Steel in Auto Body Construction
- It is lighter in weight.
- It has higher thermal conductivity.
- It is more resistant to corrosion.
- It is naturally reflective (luster).
(ii) Safety Precaution Observed When Repairing Aluminium Panel
- The surface must be free from dirt.
- The aluminium panels must be kept on plane surface.
- It should be separated from steel body parts.
- Excess heat should be avoided.