Standard G-Codes for CNC Lathes

• G0 - Rapid Movement

• G1 - Linear Feed Movement

• G2 - Clockwise Interpolation - Circular Movement

• G3 - Counter Clockwise Interpolation - Circular Movement

• G4 - Dwell

• G9 - Exact Stop

• G10 - Set Data

• G17 - XY Machine Plane Selection

• G18 - ZX Machine Plane Selection

• G19 - YZ Machine Plane Selection

• G20 - Machine is Programmed in Inches

• G21 - Machine is Programmed in Millimeters

• G28 - Return Home (First Reference Position)

• G30 - Return to the Second Reference Position

• G40 - Cancel the Turning Tool Nose Radius Compensation

• G41 - Turning Tool Nose Radius Compensation - Left

• G42 - Turning Tool Nose Radius Compensation - Right

• G50 - Maximum Spindle Speed Limit

• G52 - Local Coordinate System Setting

• G53 - Machine Coordinate System Setting

• G54 - Work Offset / Work Coordinate System

• G55 - Work Offset / Work Coordinate System

• G56 - Work Offset / Work Coordinate System

• G57 - Work Offset / Work Coordinate System

• G58 - Work Offset / Work Coordinate System

• G59 - Work Offset / Work Coordinate System

• G80 - Cancel a Canned Cycle

• G81 - Drilling Canned Cycle

• G82 - Drilling Canned Cycle

• G83 - Peck Drilling Canned Cycle

• G84 - Tapping Canned Cycle

• G85 - Boring Canned Cycle

• G86 - Boring Cycle

• G90 - Absolute Programming

• G91 - Incremental Programming

• G92 - Thread Cutting Canned Cycle

• G96 - Constant Surface Speed Selection

• G97 - Spindle Speed Selection

• G98 - Feed Rate Per Minute

• G99 - Feed Rate Per Revolution

Standard M-Codes for CNC Lathes

• M0 - Machine Stop / Program Stop

• M1 - Optional Stop (There is a button on the controller that allows the program to stop at this point)

• M2 - End of Program

• M3 - Spindle Rotation Counter Clockwise / Spindle Start

• M4 - Spindle Rotation Clockwise / Spindle Start

• M8 - Coolant On (There are normally more coolant codes)

• M9 - Coolant Off

• M10 - Chuck Clamp

• M11 - Chuck Unclamp

• M17 - Turret Rotation Forward

• M18 - Turret Rotation Reverse

• M19 - Orientate the Spindle

• M30 - End of the Program / Reset the Program

• M36 - Parts Catcher Extend, On

• M37 - Parts Catcher Retract, Off

• M98 - Subprogram Call, Jump-to

• M99 - Subprogram End

Terms To Understand

• M - Codes - Miscellaneous CNC function programming in the standard G-Code programming format. The M-codes vary by the machine tool builder

• Modal - A term that means that two G-Codes from the same group cannot be executed on the same line of code, or at the same time.

The Order of a CNC Program

1. The Program Number

2. A Tool Change Call

3. Define a Tool Length Offset Number

4. Define a Work Coordinate System Number

5. Tool Path Code

6. Axis Zero Return

7. End of the Program

FACING THE PART - G CODE PROGRAM

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O0010 (PROGRAM NUMBER)

(LATHE PART)

G50S3000 (MAXIMUM SPINDLE SPEED)

T0101 (TOOL CALL, TOOL OFFSET CALL)

G96S1500M3 (CONSTANT SURFACE SPEED, TURN SPINDLE ON AT 1500RPM)

(FACING OPERATION)

G0G54G90X1.85Z0.0M8 ( G54 WORK COORDINATE, RAPID TO X1.85, Z0, COOLANT ON)

G1G99X0.0F.003 (FACE PART TO X0.0)

G0Z.100 (RAPID TO Z.1)

G0X2.0 (RAPID TO X2.0)

G0X6.5M9 (RAPID TO X 6.5, COOLANT OFF)

M30 (END OF PROGRAM)

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Turning The Outside Diameter - G Code Program

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O0011 (PROGRAM NUMBER)

(LATHE PART)

G50S3000 (MAXIMUM SPINDLE SPEED)

T0101 (TOOL CALL, TOOL OFFSET CALL)

G96S1500M3 (CONSTANT SURFACE SPEED, TURN SPINDLE ON AT 1500RPM)

(OD TURN OPERATION)

G0G54G90X1.75Z0.05M8 (G54 WORK COORDINATE, RAPID TO X 1.75, Z.05, COOLANT ON)

G1G99Z-4.010F.006 (FINISH TURN PART)

G0X1.85 (RAPID ABOVE PART)

G0Z.1 (RAPID TO Z.1)

G0X6.5M9 (RAPID TO X6.5, COOLANT OFF)

M30 (END OF PROGRAM)

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