Tooth geometry of plain milling cutters In a plain milling cutter, what is the name of the gash surface directly adjacent to the cutting edge upon which the chip initially flows and impinges?

Introduction / Context:
Understanding tooth nomenclature on milling cutters helps in resharpening, specifying geometry, and predicting chip flow. The surface that guides the chip right at the edge is especially important for rake and cutting action.

Given Data / Assumptions:

• Plain (slab) milling cutter with peripheral teeth.
• Standard terminology: face, land, fillet, lead.
• Chip exits along the tooth face.

Concept / Approach:
The face of a milling cutter tooth is the surface over which the chip flows immediately after being sheared by the cutting edge; it determines the rake angle. The land is a narrow surface behind the cutting edge (on the periphery) that provides strength and relief. The fillet is the curved surface blending the face and the body. The lead typically refers to axial advance in helical teeth or feed direction, not a tooth surface.

Step-by-Step Solution:

Verification / Alternative check:
Machining handbooks illustrate face as the chip-bearing surface on milling teeth; relief and land are separate features.

Why Other Options Are Wrong:
Fillet: a blending radius, not the chip-flow surface.Land: narrow peripheral support area behind the edge, not the chip face.Lead: not a tooth surface term here; relates to helical advance.

Common Pitfalls:
Confusing land with face when inspecting small cutters; verify by locating the rake surface involved in chip flow.

Final Answer:

Face