Single-point cutting tools – definition check: The back rake angle is the angle by which the tool face is inclined towards the back (away from the cutting edge) in the longitudinal plane. Is this statement correct?

Introduction / Context:
Tool geometry controls chip flow, cutting forces, heat, and surface finish. Back rake angle and side rake angle are fundamental rake parameters for single-point tools used in turning and shaping.

Given Data / Assumptions:

• ASA/ORS style definitions for tool angles.
• Reference planes: base reference and longitudinal plane through the cutting edge.
• Right-hand tool example for discussion.

Concept / Approach:
Back rake angle is measured in the plane that is parallel to the tool shank’s longitudinal axis and passes through the cutting edge. A positive back rake means the face slopes away from the cutting edge toward the shank (“back”), guiding chip flow and lowering cutting force. Negative rake strengthens the edge for hard materials.

Step-by-Step Solution:

Verification / Alternative check:
Compare with tool geometry handbooks: back rake (longitudinal) versus side rake (transverse); sketches confirm the inclination direction.

Why Other Options Are Wrong:
Limiting validity to specific tool types or feed rates is incorrect; back rake is a geometric definition independent of feed and applies to all single-point tools.

Common Pitfalls:
Confusing back rake with clearance angles; clearance prevents rubbing of the flank, while rake controls chip flow and cutting action.

Final Answer:
Agree