A single point tool specified as 8-14-6-6-6-15-4 has a back rake angle of-

Concept:

Tool designation or tool signature under ASA (American Standards Association) system is given in this order:

Back rake angle (αb) – Side rake angle (αs) – End relief angle (γe) – Side relief angle (γs) – End cutting edge angle (Ce) – Side cutting edge angle (Cs) – Nose radius (R)

αb – αs – γe – γs – Ce – Cs – R

8°, 14°, 6°, 6°, 6°, 15°, 4 

Back rake angle (αb) = 8°

Side rake angle (αs) = 14°

End relief angle (γe) = 6°

Side relief angle (γs) = 6°

End cutting edge angle (Ce) = 6°

Side cutting edge angle (Cs) = 15°