Page 133 - Turner 1st sem Practicals

Job sequence

• Hold the job in a 4 jaw chuck and true it. Be sure the graduated collar is set after the
• Face one end and centre drill the job. backlash is eliminated.

• Drill the job with a Ø 12 mm drill bit throughout. • Turn Ø45 mm to the maximum length.
Clean the spindle of the tailstock shank and • Reverse the job and reset it.
sleeve before use. • Face the other end to maintain a 40 mm total length.
• Fix a Ø20 mm drill in the tailstock spindle. • Turn the remaining portion to Ø45 mm.
• Feed the Ø20 mm drill to 25 mm length with the help of • Deburr the job and check the dimensions.
the graduated collar of the tailstock.
• When feeding the drill bit for step drilling, first touch
the drill to Ø12 mm hole and note down the reading on
the graduated collar of the tailstock.

The instructor may give demo to the trainees to practice the drill grinding

120 Producltion & Manufacturing : Turner - Exercise 1.3.38