# Tool Geometry 240

This class identifies the major tool angles that impact the turning operation. Includes an Interactive Lab.

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## Class Details

Class Name:
Tool Geometry 240
Description:
This class identifies the major tool angles that impact the turning operation. Includes an Interactive Lab.
Version:
1.0
Difficulty:
Intermediate
Number of Lessons:
16
Spanish, Chinese
Related 2.0 Class:
Lathe Tool Geometry 351

## Class Outline

• Objectives
• Importance of Tool Geometry
• The Face and Flanks
• Effect of Workpiece Material
• Effect of Tool Material
• Back and Side Rake Angles
• Recommended Rake Angles
• End and Side Relief Angles
• Recommended Relief Angles
• End and Side Cutting Edge Angles
• Recommended Cutting Edge Angles
• Tool Signature
• Carbide Insert Classification
• Tool Geometry for Various Operations
• Summary

## Objectives

• Describe the importance of tool geometry.
• Identify the face and flanks of a tool.
• Describe the effect of workpiece material on machining.
• Describe the effect of tool material on machining.
• Identify back and side rake angles.
• Define back and side rake angles.
• Describe the importance of rake angles.
• Identify end and side relief angles.
• Define end and side relief angles.
• Describe the importance of appropriate relief angles.
• Identify end and side cutting edge angles.
• Define end and side cutting edge angles.
• Describe the importance of cutting edge angles.
• Describe the importance of nose radius.
• Describe the role of tool signature.
• Describe carbide insert classification.
• Identify the main cutting surfaces for turning.

SME
• CMfgT

## Glossary

Vocabulary Term Definition
American National Standards Institute A private, non-profit organization that administers and coordinates voluntary standards and systems. Tool signatures and carbide insert classifications are standardized by ANSI.
back rake angle If viewed from the side facing the end of the workpiece, it is the angle formed by the face of the tool and a line parallel to the floor. A positive back rake angle tilts the tool face back, and a negative angle tilts it forward and up.
carbide A common cutting tool material developed by the combination of carbon with usually chromium, tungsten, or titanium that is used in metal cutting tools for its hardness and wear resistance.
carbide insert A cutting bit made of hard carbide material that has multiple cutting edges. Once a cutting edge is excessively worn, it can be indexed to another edge, or the insert can be replaced.
depth of cut The thickness of the material that is removed by one pass of the cutting tool over the workpiece.
discontinuous chip A chip that easily fractures from the workpiece into small, separate pieces. Brittle materials tend to create discontinuous chips.
end cutting edge angle If viewed from above looking down on the cutting tool, it is the angle formed by the end flank of the tool and a line parallel to the workpiece centerline. Increasing the end cutting edge angle tilts the far end of the cutting edge away from the workpiece.
end relief angle If viewed from the side facing the end of the workpiece, it is the angle formed by the end flank of the tool and a vertical line down to the floor. Increasing the end relief angle tilts the end flank away from the workpiece.
face The flat surface of a single-point tool into which the workpiece rotates during a turning operation. On a typical turning setup, the face of the tool is positioned upwards.
feed The rate that the cutting tool and the workpiece move in relation to one another. For turning, feed is the rate that the single-point tool is passed along the outer surface of the rotating workpiece.
flank A flat surface of a single-point tool that is adjacent to the face of the tool. During turning, the side flank faces the direction that the tool is fed into the workpiece, and the end flank passes over the newly machined surface.
hardness The ability of a material to resist penetration and scratching. Hardness is one of the key properties of cutting tool materials.
high-speed steel A type of tool steel used to machine metals at high cutting speeds. HSS is relatively inexpensive and offers excellent toughness.
lead angle A common name for the side cutting edge angle. If a toolholder is built with dimensions that shift the angle of an insert, the lead angle takes this change into consideration.
nose radius The rounded tip on the cutting edge of a single-point tool. The greater the nose radius, the greater the degree of roundness at the tip. A zero degree nose radius creates a sharp point.
side cutting edge angle If viewed from above looking down on the cutting tool, it is the angle formed by the side flank of the tool and a line perpendicular to the workpiece centerline. A positive side cutting edge angle moves the side flank into the cut, and a negative angle moves the side flank out of the cut.
side rake angle If viewed behind the tool down the length of the toolholder, it is the angle formed by the face of the tool and the centerline of the workpiece. A positive side rake angle tilts the tool face down toward the floor, and a negative angle tilts the face up and toward the workpiece.
side relief angle If viewed behind the tool down the length of the toolholder, it is the angle formed by the side flank of the tool and a vertical line down to the floor. Increasing the side relief angle tilts the side flank away from the workpiece.
tool geometry The collective angles formed by the dimensions of a cutting tool that make a tool unique.
tool signature The numerical code that describes all the key angles of a given cutting tool. A tool signature may be used for HSS or carbide inserts.
toughness The ability of a material to absorb energy without breaking or fracturing. Toughness is a key property of cutting tools because it determines the ability of a tool to withstand a sudden stress.