CNC PROGRAMMING G CODES AND M CODES

CNC PROGRAMMING  G CODES AND M CODES 

Computer Numerical Control (CNC) machines use a set of instructions called G-codes and M-codes to control their operation. In this blog, we will delve into what these codes are, how they work, and their applications.

What are G-codes?

G-codes are a set of instructions that tell a CNC machine tool how to move and operate. These codes are used to control the tool's movement, speed, and position during machining operations. G-codes can be thought of as a language that CNC machines use to communicate with their controllers.

G-codes typically start with the letter "G," followed by a number. The number represents a specific command, such as moving the tool to a specific position or changing the feed rate. For example, G00 is a rapid positioning command, which moves the tool rapidly to a specified position without cutting any material. G01 is a linear interpolation command, which moves the tool at a specified feed rate in a straight line.

What are M-codes?

M-codes are a set of instructions that control auxiliary functions of a CNC machine tool, such as turning on and off coolant, spindle speed, and other machine functions. M-codes can also be thought of as a language that CNC machines use to communicate with their controllers.

M-codes typically start with the letter "M," followed by a number. The number represents a specific command, such as turning on the spindle or stopping the machine. For example, M03 is a spindle on clockwise command, which turns on the spindle in a clockwise direction. M05 is a spindle stop command, which stops the spindle from rotating.

How do G-codes and M-codes work together?

G-codes and M-codes work together to control the operation of a CNC machine tool. G-codes control the tool's movement and position, while M-codes control auxiliary functions. The CNC machine tool controller interprets the G-codes and M-codes and executes them in sequence to perform a machining operation.

For example, to drill a hole in a workpiece, the G-code program might include commands to move the tool to the correct position, set the feed rate, and start the spindle. The M-code program might include commands to turn on the coolant to keep the tool cool and lubricated during the drilling operation.

Applications of G-codes and M-codes

G-codes and M-codes are used in a wide range of CNC machining applications, from simple drilling and milling operations to complex machining of aerospace components. They are essential for producing precise and accurate parts and components, as they allow for precise control of tool movement and machine functions.

In addition to their use in traditional CNC machining applications, G-codes and M-codes are also used in 3D printing and additive manufacturing. They are used to control the movement of the 3D printing nozzle and other machine functions, such as bed temperature and cooling.

1. G00: Rapid positioning
2. G01: Linear interpolation
3. G02: Circular interpolation clockwise
4. G03: Circular interpolation counterclockwise
5. G04: Dwell
6. G20: Inch programming
7. G21: Metric programming
8. G28: Return to home position
9. G40: Tool radius compensation off
10. G41: Tool radius compensation left
11. G42: Tool radius compensation right
12. G43: Tool length compensation +
13. G44: Tool length compensation -
14. G50: Scaling
15. G54-G59: Workpiece coordinate system selection
16. G71: Stock removal in X axis
17. G72: Stock removal in Z axis
18. G73: Peck drilling in Z axis
19. G74: Peck drilling in X axis
20. G76: Thread cutting cycle
21. G80: Canned cycle cancel
22. G90: Absolute programming
23. G91: Incremental programming
24. G94: Feed per minute
25. G98: Canned cycle initial point return
26. G99: Canned cycle R point return

In addition to G codes, CNC turning also uses M codes to control auxiliary functions such as coolant and spindle control. Here is a list of M codes commonly used for CNC turning with Fanuc control:

1. M00: Program stop
2. M02: End of program
3. M03: Spindle on clockwise
4. M04: Spindle on counterclockwise
5. M05: Spindle stop
6. M08: Coolant on
7. M09: Coolant off
8. M19: Spindle orientation
9. M98: Subprogram call
10. M99: Subprogram end

These G and M codes are just some of the most commonly used codes in CNC turning with Fanuc control. However, there are many more codes and variations that may be used depending on the specific application and machine being used. It is important to have a thorough understanding of these codes to program and operate CNC turning machines effectively.