Page 54 - Turner 1st sem Practicals

Job sequence

TASK 1: Chipping practice

• Apply marking media and mark the depth of metal to be • Hold chisel at approximately at 35° angle of inclination
removed by chipping. Punch the marked line with a dot in chipping position.
punch. • Hold the hammer at the end of the handle to get more
• Hold the job firmly in the vice. leverage.

If necessary give a wooden support below the Caution : Chisel should be free of mushroom
work piece so that the marked line should be head.
above the vice jaw face. Hammer handle should be securely fixed with
• Select a flat chisel 20mm width with a proper cutting eye hole with a wedge.
edge. Use goggles while chipping.
• Select a ball peen hammer with required weight. Use a chipping guard behind the vice to arrest
the flying chips.

TASK 2: Chisel grinding

• Check the grinding machine and check whether safety • Give the minimum pressure to create the cutting point.
guards are properly fitted.
• Check angle with help of bevel protractor.
• Switch on the grinding machine.
Ensure that there is enough coolant in the
• Rest the body of the chisel on the tool rest.
container.
• The body of the chisel must be at an angle of 30° in such
a way as to get 60°.

Skill Sequence

Hints on chipping
This shall help you to
• observe safe practices while chipping.

Before commencing the chipping operation we must ensure
the following.
The hammer-head must be properly secured. (Fig 1)

Install chip- guard against chips flying off. (Fig 3)

Wipe off oily substances, if any, from the face of the
hammer.
The chisel head must be free from mushroom formation.
(Fig 2)
Wear safety goggles.
Remove bangles and wrist watches.

42 Producltion & Manufacturing : Turner - Exercise 1.2.14