G-Code is the common name for the programming language of CNC Machines.Somewhat of a general, catchall term for CNC programming language. Very few machines adhere to this standard today. There are as many varations as there are manufacturers.
This is how I think of G-Code. It is a simple language built off of the Cartesian Coordinate System for motion control. That is a mouthful. I don’t know if that is exactly right, but you will get my meaning in a second when we go through some code line by line. You will remember your High School Geometry soon enough. For the real pros out there, you know there is much more to G-Code then that, but it is a good place to start thinking about it.
You will see many variations of the G-Code name like:
Gcode
gcode
G-Code
g-code
G Code
G-Code
Are there other “Codes?”
In a word…Yes.We will get to that information in just a minute. G-code is also the name of any command in a CNC program that begins with the letter G. G-Codes generally tell the machine to perform an action. G-Codes can tell machines to move a certain distance in the X-Axis for example.Or, make a quick move to another location. Or, move in an arcing fashion while milling. An on and on and on.
Here are some examples of G-Codes
Remember these codes change to a certain degree between CAM Software packages and CNC Machine Manufacturers.
G00 Rapid positioning
G01 Linear interpolation
G02 CW circular interpolation
G03 CCW circular interpolation
G04 Dwell
G20 Programming in inches
G21 Programming in mm
G28 Return to home position
G40 Tool radius compensation off
G41 Tool radius compensation left
G42 Tool radius compensation right
G43 Tool offset compensation positive
G44 Tool offset compensation negative
Why does G-Code Change?
We humans like flexibility. We also like standards. G-Codes are standardized in a certain sense. Once you start to be able to read it, you can read just about any flavor of it. That is the standardized part.
All CNC machines are not created in the same way. Even identical machines are different to a certain degree. They may not have the same tools loaded or they have been slightly modified to produce a certain type of part. Interesting how people like to customize.
That is why g-code programs are not the same. You need some flexibility in the programming to accommodate all situations. Couple that with the fact that every manufacturer thinks their version is the best and you get a myriad of G-Codes out there.
Many manufacturers also try to force you to only use their code. For example, they give you a design interface to make parts and a CAM interface to produce code. They lock you into their “Black Box” so you can’t go elsewhere for service and support. They lock you in their “Family.” Sometimes they make up a completely different kind of G-Code language that no one can understand but them. They do that to keep your hands tied up.
What is an M-Code?
M-Codes are related to G-Codes. M-Codes control different machine functions.Some of these different functions are turning the CNC machine off and on.Flipping the spindle on or off. Turning a plasma torch on or off. Turning coolant on or off. You get the idea. When programming your CNC machine you may need to perform these functions.
Like G-Code, M-Codes vary from manufacturer to manufacturer and from machine to machine. As you can imagine you would need an M-Code for turning a plasma torch on and off on a CNC Plasma Cutting Machine.You don't need an M-code to turn a CNC machine spindle on and off though. Hey, the machine doesn’t even have a spindle. It’s a plasma cutter!
CNC Information Free Community Site:
If you would like to know more about CNC, head on over to http://www.cncinformation.com
You can join for Free and you get two free CNC ebooks. One is a GCode Quick Guide and the other is the CNC Info Site eBook. You also get access to the Free Video Series...Image to CNC Art when you join the community.
No comments:
Post a Comment