Question 1
(a) Explain why pressure is released on the backward stroke when filing.
(b) State two methods of preventing clogging of file teeth.
(c) (i) Sketch to show the difference between the two sets of jaw chuck.
(ii) State the difference in the uses of the two sets of jaws.
Observation
Part (a) posed no difficulty to the candidates. Some of the candidates were not able to provide correct answers to parts (b) and (c). The required responses to the questions are as follows:
(a) A file cuts on the forward stroke, the teeth are designed not to cut during the backward stroke and hence pressure is released on the backward stroke.
(b) Stating two methods of preventing clogging of file teeth:
(i)Select the correct file for the work;
(ii) Rubbing the teeth with chalk before using it.
(c) Sketch to show the difference between a 3-Jaw chuck and 4-Jaw chuck:
(ii) Stating the difference in the uses of the two chucks:
A 3-Jaw chuck is used to hold round objects while a 4 Jaw chuck is used to hold irregular shaped objects.