Single-point cutting tool nomenclature The angle formed between the tool face and a plane parallel to the tool base (reference plane) is called what?
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ARake angle
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BCutting angle
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CClearance angle
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DLip angle
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EApproach angle
Answer
Correct Answer: Rake angle
Explanation
Introduction / Context:Tool geometry terms—rake, clearance, and edge angles—govern chip formation, cutting forces, heat generation, and tool life. Accurate definitions are essential for setup and troubleshooting.
Given Data / Assumptions:
- Orthogonal tool geometry terminology per standard reference planes.
- Plane parallel to base is the reference (rake) plane.
Concept / Approach:The rake angle is the inclination of the tool face relative to the reference plane. Positive rake promotes easier shearing and lower forces; negative rake strengthens the edge for hard materials. Clearance (relief) is the angle between the flank and the work surface to prevent rubbing.
Step-by-Step Solution:Identify the surfaces: “face of the tool” versus “plane parallel to the base.”By definition, this is the rake angle that controls chip flow direction and shear deformation.
Verification / Alternative check:Standard tool signature formats (e.g., ASA, ORS) list rake angles with respect to reference planes parallel to the base.
Why Other Options Are Wrong:
- Cutting angle/lip angle refer to resultant included angles at the cutting edge, not the face-to-base relation.
- Clearance angle is between flank and work surface.
- Approach angle relates the cutting edge to feed direction.
Common Pitfalls:Mixing rake and clearance; forgetting that rake deals with chip flow while clearance prevents rubbing.
Final Answer:Rake angle