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South Bend lathe Chip Formation Chip Breakers Feeds and Speeds Tool Materials. Tool Properties Tool Wear Surface Finishes Cutting Fluids CNC Lathes. Fundamentals of Cutting. South Bend Engine Lathe. Chip Formation. Discontinuous Continuous Built up edge. Chip Breakers.
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South Bend lathe Chip Formation Chip Breakers Feeds and Speeds Tool Materials Tool Properties Tool Wear Surface Finishes Cutting Fluids CNC Lathes Fundamentals of Cutting
South Bend Engine Lathe
Chip Formation Discontinuous Continuous Built up edge
Chip Breakers • On the Cutting Tool • In the Material • Inclusions • Sulfur
Speeds, Depth of Cut • Depth of Cut • Speed
Feed Rates or
Cutting Time Considerations • Material removal rate • Time to Cut
Tool Materials • High SpeedSteel (HSS) • CoatedCarbideInserts
High Hardness Resist Abrasion Resist Chipping Hot Hardness Resist BulkDeformation (E) Chemical Stability Adequate Thermalproperties Consistent ToolLife Geometry Tool Properties
Tool Wear • slow death mechanisms: gradual wear on flanks, or rake face of tool (crater) • abrasion, adhesion, diffusion, chemical • sudden death mechanisms: unpredictable, catastrophic failure • brittle fracture, chipping, plastic deformation
Tool Life • Taylor's Equation: Surface Speed • Variation in material hardness • within piece and piece to piece • Variation in tool material and geometry • Vibrations • Changing surface characteristics of workpiece
Surface Finishes • Tool Geometry and Feed rate
Surface Finishes • Surface Speed and Depth of Cut
Cutting Fluids • Reduces Cutting Temperature • dimensional stability • reduces thermal tool wear • Acts as Lubricant • reduces forces and energy consumption
Cutting Fluids • Flood Cooling • lowers temperature • reduces oxidation • Mist Cooling • Better Visibility • gets to inaccessible areas
Effects of Coolants • On workpiece • cracking, staining, chemical attack • On machines • bearings and slideways • On environment • breathing apparatus, and disposal