Page 55 - CITS - Fitter Trade Practical - Volume -2

FITTER - CITS

Fig 7

While turning the wrench, the movement should be well balanced. Any extra pressure on one side will spoil the
tap alignment and can also cause breakage of the tap.
Continue cutting the thread. Turn backwards frequently, about quarter turn, to break the chip. (Fig 8) Stop and turn
backwards also when some obstruction to movement is felt.

Fig 8

Note: Use a cutting fluid while cutting the thread.
Cut the thread until the tap is fully inside the hole being threaded.
Finish and clean up using intermediate and plug tap. The intermediate and plug tap will not cut any thread if the
tap has entered the hole fully.
Remove the chips from the work with a brush.
Check the threaded hole with a matching screw.

Clean the tap with a brush, and place it back on the stand (Fig 9)

Fig 9

40

CITS : C G & M - Fitter - Exercise 62