1. Lathe Operations

3. Numerical Control CNC or Computer Numerical Control is a term derived from NC or Numerical Control. NC refers to Control of a process or automatic operation of a machine by using symbolic codes consisting of characters and numbers. NC was introduced in late 40’s to control machine tools such as Drilling and Milling machines. One of the first applications of NC machine tool was in production of helicopter rotor blades and ship propellers.

4. CNC System

5. CNC Axes +X +Z

6. Motion Statements G00Linear Movement (rapid) G01Linear Movement (feed) G02Circular Movement (cw feed) G03Circular Movement (ccw feed) CNC Programming

7. CNC Axes +X +Z 35 25 Tool at (25, 35)

8. CNC Axes +X +Z Tool at (25, 35) G00 X0 Z35 G00 X0 Z0

9. CNC Programming X Z

10. Initial Diameter = 10 mm Final Diameter = 6 mm Depth of cut = 1 mm Width of cut = 8 mm G00 X4 Z1 G01 Z-8 G00 X4 Z1 G00 X 3 G01 Z-8 G00 X4 Z1

11. CNC machine tools & programming Preparatory NC Codes G00Linear Movement (rapid) G01Linear Movement (feed) G02Circular Movement (cw) G03Circular Movement (ccw) G70Inch units G71Metric units G90Absolute dimensions G91incremental dimensions

12. CNC machine tools & programming Miscellaneous NC Codes M02End of program M03Clockwise rotation of spindle M04Counter-clockwise rotation of spindle M05Stop rotation of main spindle M07Coolant on M09Coolant off

13. CNC machine tools & programming Sample Program N01 G71 G90 M03 M07 N02 G00 X9 Z1 N03 G01 Z-25 N04 G00 X10 Z1 N05 G00 X8 Z0 N06 G01 X9 Z12 N07 G00 X20 Z20 N08 M05 M09

14. Programming for CNC machine tools TWO APPROACHES Manual part programming NC program generation from CAD models

15. CNC Programming

20. Gouging

21. CNC Programming r min