G-Code from the Machine’s Perspective
There are a handful of basic concepts you should know before we dive into what individual g-codes do and how to use them. Most importantly, you must understand what a computer language is and how to think about it.G-Code is a computer language aimed at telling your machine what to do. The trouble with computer languages like g-code is that unlike people, machines are very literal. They assume you know exactly what you want, they don’t question you about it, and they immediately try to comply, even if that means hurting themselves!
For that reason, you need to adopt an approach of being protective of your machine, perhaps even over protective bordering on paranoid. It will do exactly what you tell it to even if that means rapiding a spinning cutter with 20HP behind it directly into your expensive fourth axis and destroying it. There’s no need to be afraid of g-code, but it is important to understand it and to respect it in order to be successful. Getting to that stage is another excellent reason to spend time learning the g-code. It will give you insights into your machine that enable you to extract more performance and to protect it better from accidents. (http://www.cnccookbook.com/CCCNCGCodeBasics.htm)
|
Code
|
Category
|
Function
|
Notes |
Tutorials
|
||
| G00 |
Motion
|
Move in a straight line at rapids speed. | XYZ of endpoint | G00 and MDI.
|
||
| G01 |
Motion
|
Move in a straight line at last speed commanded by a (F)eedrate | XYZ of endpoint | G01 and MDI.
|
||
| G02 |
Motion
|
Clockwise circular arc at (F)eedrate | XYZ of endpoint
IJK relative to center R for radius |
G02 / G03 Tutorial and Examples | ||
| G03 |
Motion
|
Counter-clockwise circular arc at (F)eedrate | XYZ of endpoint
IJK relative to center R for radius |
G02 / G03 Tutorial and Examples | ||
| G04 |
Motion
|
Dwell: Stop for a specified time. | P for milliseconds
X for seconds |
Precise Timing and Speed: Dwell, Exact Stop, Backlash Compensation | ||
| G05 |
Motion
|
FADAL Non-Modal Rapids | ||||
| G09 |
Motion
|
Exact stop check | Precise Timing and Speed: Dwell, Exact Stop, Backlash Compensation | |||
| G10 |
Compensation
|
Programmable parameter input | ||||
| G15 |
Coordinate
|
Turn Polar Coordinates OFF, return to Cartesian Coordinates | G15/G16 Polar Coordinates | |||
| G16 |
Coordinate
|
Turn Polar Coordinates ON | G15/G16 Polar Coordinates | |||
| G17 |
Coordinate
|
Select X-Y plane | CNC G-Code Coordinates | |||
| G18 |
Coordinate
|
Select X-Z plane | CNC G-Code Coordinates | |||
| G19 |
Coordinate
|
Select Y-Z plane | CNC G-Code Coordinates | |||
| G20 |
Coordinate
|
Program coordinates are inches | G20 and G21: Unit Conversion | |||
| G21 |
Coordinate
|
Program coordinates are mm | G20 and G21: Unit Conversion | |||
| G27 |
Motion
|
Reference point return check | G28: Return to Reference Point | |||
| G28 |
Motion
|
Return to home position | G28: Return to Reference Point | |||
| G29 |
Motion
|
Return from the reference position | G28: Return to Reference Point | |||
| G30 |
Motion
|
Return to the 2nd, 3rd, and 4th reference point | G28: Return to Reference Point | |||
| G32 |
Canned
|
Constant lead threading (like G01 synchronized with spindle) | ||||
| G40 |
Compensation
|
Tool cutter compensation off (radius comp.) | ||||
| G41 |
Compensation
|
Tool cutter compensation left (radius comp.) | ||||
| G42 |
Compensation
|
Tool cutter compensation right (radius comp.) | ||||
| G43 |
Compensation
|
Apply tool length compensation (plus) | ||||
| G44 |
Compensation
|
Apply tool length compensation (minus) | ||||
| G49 |
Compensation
|
Tool length compensation cancel | ||||
| G50 |
Compensation
|
Reset all scale factors to 1.0 | ||||
| G51 |
Compensation
|
Turn on scale factors | ||||
| G52 |
Coordinate
|
Local workshift for all coordinate systems: add XYZ offsets | ||||
| G53 |
Coordinate
|
Machine coordinate system (cancel work offsets) | ||||
| G54 |
Coordinate
|
Work coordinate system (1st Workpiece) | ||||
| G55 |
Coordinate
|
Work coordinate system (2nd Workpiece) | ||||
| G56 |
Coordinate
|
Work coordinate system (3rd Workpiece) | ||||
| G57 |
Coordinate
|
Work coordinate system (4th Workpiece) | ||||
| G58 |
Coordinate
|
Work coordinate system (5th Workpiece) | ||||
| G59 |
Coordinate
|
Work coordinate system (6th Workpiece) | ||||
| G61 |
Other
|
Exact stop check mode | Precise Timing and Speed: Dwell, Exact Stop, Backlash Compensation | |||
| G62 |
Other
|
Automatic corner override | ||||
| G63 |
Other
|
Tapping mode | ||||
| G64 |
Other
|
Best speed path | ||||
| G65 |
Other
|
Custom macro simple call | Subprograms and Macros | |||
| G68 |
Coordinate
|
Coordinate System Rotation | G68 and G69 Tutorial and Examples | |||
| G69 |
Coordinate
|
Cancel Coordinate System Rotation | G68 and G69 Tutorial and Examples | |||
| G73 |
Canned
|
High speed drilling cycle (small retract) | ||||
| G74 |
Canned
|
Left hand tapping cycle | ||||
| G76 |
Canned
|
Fine boring cyle | ||||
| G80 |
Canned
|
Cancel canned cycle | ||||
| G81 |
Canned
|
Simple drilling cycle | ||||
| G82 |
Canned
|
Drilling cycle with dwell (counterboring) | ||||
| G83 |
Canned
|
Peck drilling cycle (full retract) | ||||
| G84 |
Canned
|
Tapping cycle | ||||
| G85 |
Canned
|
Boring canned cycle, no dwell, feed out | ||||
| G86 |
Canned
|
Boring canned cycle, spindle stop, rapid out | ||||
| G87 |
Canned
|
Back boring canned cycle | ||||
| G88 |
Canned
|
Boring canned cycle, spindle stop, manual out | ||||
| G89 |
Canned
|
Boring canned cycle, dwell, feed out | ||||
| G90 |
Coordinate
|
Absolute programming of XYZ (type B and C systems) | ||||
| G90.1 |
Coordinate
|
Absolute programming IJK (type B and C systems) | ||||
| G91 |
Coordinate
|
Incremental programming of XYZ (type B and C systems) | ||||
| G91.1 |
Coordinate
|
Incremental programming IJK (type B and C systems) | ||||
| G92 |
Coordinate
|
Offset coordinate system and save parameters | ||||
|
M-Codes
|
||||||
|
Code
|
Category
|
Function
|
Notes |
Tutorials
|
||
| M03 |
M-Code
|
Spindle ON (CW Rotation) | M03 and MDI. | |||
| M04 |
M-Code
|
Spindle ON (CCW Rotation) | ||||
| M05 |
M-Code
|
Spindle Stop | M05 and MDI. | |||
| M06 |
M-Code
|
Tool Change | ||||
| M30 |
M-Code
|
End of Program, Rewind and Reset Modes | ||||