Sweetspot G-code: Zig-Zag Pattern

G-code is remarkably easy to understand, once you master a few commands and become familiar with the required syntax. Every line is in clear text (like HTML) and the commands logically positioned with the arguments that they operate on. The full scope of the allowable syntax is beyond the purpose of this short tutorial. For a complete description, look at the G-code Primer (The NIST RS274/NGC Interpreter).

At Think & Tinker, we have the system origin (X0, Y0, Z0) defined in the lower left corner of the cutting table, near the corner of the FRONT and LEFT edges. The positive (+) X direction is to the right. The positive (+) Y direction is towards the BACK of the table. As you might expect, the positive (+) Z direction is vertically up from the surface.

Line numbers (Command starts with a N) are totally optional, but VERY handy for editing long programs. Controller software, like Mach3, often show line numbers by default.

Leading and trailing ZEROS are ignored by the G-code interpreter. They are shown in the code for clarity and can make troubleshooting much easier later on.

The code shown in the table below is what we use for ANY of our tools with cutting diameters 1/8 in. and smaller. The only things that change are the feedrates (F commands).

One of the things that you will notice about the following code is that the main section is very repitive. That makes it easy to modify by cutting and pasting blocks of text, as long as you remember set the feedrate (FXX) for each step. The code areas marked in green are essentially a header and footer that might be slightly different depending on your controller software and the way you define you local origin. The codes used in this tutorial are so generic that they should work with virtually any controller that supports NIST RS274 (V3).