G-code Overview and Related Resources for Machinists
G-code, or preparatory code, is the most widely used computer numerical control (CNC) programming language. It allows CNC programmers to give directions to the machine tool with specific paths that transform a design into a solid object.
In this article, we’ll take a look at the origins of this language, give a brief overview of its functions, and provide some recommended resources that will bolster your comprehension of G-code.
History of G-code in a nutshell
In the late 1950s, MIT’s Servomechanisms Laboratory was the first to successfully implement a numerical control programming language. By the 1970s, FANUC and Siemens both pushed for the code to be standardized in manufacturing as a predominant issue was the inconsistency of the programming language and machine tool capability. Later that decade, 3D Computer Aided Design/Computer Aided Machining (CAD/CAM) systems – which optimized the manufacturing process due to their ability to decrease material waste, improve turnaround times and provide clear visual concepts – hit the market and by the late 80s, became the standard for use in CNC machining applications.
These computer aided systems enable the articulation of a design into G-code. Fast forward to present day, G-code continues to be developed and implemented in new ways in the metalworking industry.
Another accepted name for G-code is “preparatory code” which is just any CNC program that begins with the letter G. Overall, G-code is an action for the machine tool to perform. Some examples of G-code activated movements are:
- Rapid transport of tool
- Feed movements that result in a bored hole, a workpiece routed to specific dimension or a contour added to the edge of a workpiece
- Controlled feed in a straight line or arc
- Tool information like offset
- Switch coordinate systems
Thought the letter G has come to represent the entire computer language, there are many other letters used within the G-code premise.
Are you looking for a practical resource to better understand G and M codes specifically for CNC lathe programming? Codes in this book have been arranged in a logical way based on number, name and group number. Each section contains a quick description of the code, the command format, notes and some examples.
This book is great for beginners as it explains G-code programming through topics such as Cartesian Coordinate systems and G & M code definitions. This text also has tutorials for milling applications along with tutorials for lathe applications with included code and explanation.
Basic Programming Essentials: Learn Basic Batch, HTML, C-, and G- and M-code for CNC Milling Applications
If you are someone who is looking for an introduction to programming, this is a good door opener before you take a dive deeper into G-code. More of an elementary option, but a good way for someone who is looking to become more comfortable with the subject.
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