Course

G-code Basics for Beginners

This is a basic course for anyone who wants to learn how to read, understand and safely check simple CNC programs.

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Course description

The course “G-code Basics for Beginners” helps you build a step-by-step understanding of the basic logic of CNC programming: from control program structure and coordinates to tool movements, technological commands, editing and simulation.

The material is designed for beginners and built so that the learner does not just memorize commands, but understands what happens to the machine on each program line. Special attention is given to safe code reading, coordinate checking, finding dangerous movements and preparing a program to run.

The course is a good foundation before studying more complex topics: cycles, tool compensation, subprograms, macro programming and practical programming for specific CNC control systems.

Course price

39 EUR

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What you will learn

After completing the course, you will be able to:

understand the structure of a simple CNC program;
read G-code line by line and understand the machining sequence;
distinguish preparatory, technological and machining commands;
understand the X, Y, Z axes and the part zero;
read absolute and incremental coordinates;
understand the difference between G00, G01, G02 and G03;
find dangerous movements, especially along the Z axis;
check the spindle, feed, tool and coolant;
understand work offsets G54, G55 and G56;
perform basic NC program editing;
check a program in a simulator before practice;
understand what cycles, subprograms and simple code optimization are.

Skills in this course

G-code programming Manual CNC programming NC program reading NC program editing Program simulation Program debugging Toolpath checking CNC cycle programming Subprogram usage Program optimization

Lesson plan

Full course plan

The plan is organized by modules and moves from CNC program structure and coordinates to modes, movements, program checking, editing and the next learning level.

1 2 3 4 5 6 7 8

01
CNC program structure and G-code reading logic
In this section, you will learn what G-code is, how a control program is structured, and why the machine executes commands in the exact order in which they are written.
02
Machine coordinate system and program zero
This section explains how the machine understands the tool position, what the X, Y and Z axes are, how machine coordinates differ from work coordinates, and why the part zero is the foundation of the entire program.
03
Program modes: G90, G91, G20, G21
This section covers the basic modes that define how the machine interprets coordinates and units of measurement. These commands are especially important because they can completely change the meaning of a program.
04
Tool movements and toolpath building
This is one of the key sections of the course. You will learn how the tool moves in space, how rapid movement differs from feed movement, and how to read straight and circular toolpath segments.
05
Tool control and tool offsets, spindle, feedrate and coolant
This section covers commands that control the technological part of machining: tool selection and tool change, tool length and radius compensation, spindle speed and rotation, feedrate and coolant.
06
Practical reading of a simple milling program
In this section, you will learn how to read a simple program from beginning to end: machine preparation, tool movement, cutting passes, machining depth, stop commands and program completion.
07
Safe G-code editing for beginners
This section explains how to safely edit a simple NC program: changing coordinates, feedrate, spindle speed and comments without breaking the overall machining logic.
08
Basic introduction to cycles, subprograms and optimization
This section gives a basic introduction to more advanced G-code features. It does not require deep macro programming, but the learner should understand why cycles, subprograms and basic optimization are useful.