Question

A simple turning operation is carried out on a lathe machine at constant spindle speed. What will happen after a few turning passes?
1. Cutting velocity will increase and surface finish improves
2. Cutting velocity will decrease and surface finish deteriorates
3. Cutting velocity will increase and chattering occurs
4. Cutting velocity will decrease and chattering reduces

Answer 1

Correct Answer - Option 4 : Cutting velocity will decrease and chattering reduces

Velocity (V) = ΠDN

Where D is diameter of object

N is spindle speed in revolution per minute

By turning operation diameter of object decreases i.e. cutting velocity decreases.

Chattering is too and fro motion of cutting tool during their operation. Chattering force is directly proportion to the cutting velocity. Since cutting velocity decreases therefore chattering reduces.