Describe the names, symbols, and definitions of the cutting point and faces of a lathe cutting tool.
The cutting edges, points, and faces of the lathe tool are shown in Figure
Their names, symbols, and definitions are provided in the figure
Symbols and Definitions of Edges, Points, and Faces on a Turning Tool’s Cutting Portion
| Term | Symbol | Definition |
| Shank | The clamping part of the tool. | |
| Mounting Face | A surface on the shank or tool hole that is parallel or perpendicular to the tool’s base, used for mounting and positioning the tool during manufacturing, grinding, and measurement. | |
| Cutting Portion | The part of the tool that performs the cutting action. It is composed of elements such as the cutting edge, rake face, and flank face, which generate the chip. | |
| Rake Face | The surface of the tool over which the chip flows. | |
| Primary Rake Face (Chamfer) | When the tool’s rake face is composed of several intersecting surfaces, this is the one closest to the cutting edge. | |
| Secondary Rake Face | When the tool’s rake face is composed of several intersecting surfaces, this is the second surface from the cutting edge. | |
| Flank Face | The surface of the tool that is opposite the surface produced on the workpiece during cutting. | |
| Principal Flank Face | The flank face that intersects with the rake face to form the principal cutting edge. | |
| Auxiliary Flank Face | The flank face that intersects with the rake face to form the auxiliary cutting edge. | |
| Primary Flank Face (Land) | When the tool’s flank face is composed of several intersecting surfaces, this is the one closest to the cutting edge. | |
| Secondary Flank Face | When the tool’s flank face is composed of several intersecting surfaces, this is the second surface from the cutting edge. | |
| Principal Cutting Edge | A continuous segment of the cutting edge that starts from the point where the principal cutting edge angle is zero, and is intended to produce the transitional surface on the workpiece. | |
| Auxiliary Cutting Edge | Any cutting edge on the tool other than the principal cutting edge. It also starts from the point where the principal cutting edge angle is zero, but extends away from the principal cutting edge. | |
| Tool Nose | A very small portion of the cutting edge where the principal cutting edge and the auxiliary cutting edge meet. |
