Mechanical Engineering - Production Engineering - Discussion

Larger end cutting edge angle increases tool life. As flank is not rubbed against finished workpiece.

If you increase the rake angle the force developed will be less simultaneously power consumption less and tool life increase but this is limited up to 45 degrees. But with increase in rake angle the strength of the tool reduces. Experimentally with increase in 1 degree rake angle there is 8 to 10% reduction in forces.

Simple the angle between flank face and vertical line from the cutting edge will decrease so its thickness will reduce and hence it will resulting the weakness of tool.

As I have studied cutting edge angles do not have any effect on cutting forces, power and other factors so with the help of these factors it will be wrong to decide the tool life.

If one will consider the formula of roughness

Peak to valley roughness (h) = [f/{tan (SCEA)+cot(ECEA)}}.

Where,
f is feed.
SCEA is side cutting edge angle.
ECEA is end cutting edge angle.

So as EDEA will increase cotEDEA will decrease and in turns roughness will increase Thus tool life will decrease.

The main function of end cutting edge angle is to prevent the trailing front cutting edge of the tool from rubbing against the work. The end cutting edge angle varies from 8 to 15 degree. A large end cutting edge angle decreases tool width which in turn weakens the too and decreases tool life.

So answer is "B".

If End cutting edge angle increases, simultaniously it decreases the lip angle or wedge angle of the tool.

So, due to other factors like stress concentration, heat dissipation will decrease the tool life.

If I am wrong then let me know.