1. (a) What is sand casting?
(b) State the use of each of the following tools (i) riddle;
(ii) strike-off bar;
(iii) draw spike;
(iv) gate cutter;
(v) sprue-pins
(c)
Sketch a bellow used in the foundry shop.
Candidates who attempted this question had problems in providing the
required response to part (b) of the question. The required response to part (b) of the question are as follows:
(i) riddle is used for sieving and spreading the parting sand on the
patter in the drag; (ii) strike-off bar is used to level the sand packed in the flask. (iii) draw spike is used for drawing the pattern out of the mould after ramming.
(iv) gate cutter is used to create passages in the drag, known as gates,
for the inflow of the molten metal into the cavity and the rise of
surplus molten metal from the cavity when it is full.
(v) sprue pins are used for making holes in the cope through which the
molten metal is poured
