CNC Basics - What You Need To Get Started

Introduction

This video is about the core workflow used to run a hobbyist CNC router. It focuses on three-axis CNC routers, which are the most popular among hobbyists.

Three Main Sections of Workflow

• The basic workflow required to run these can be broken down into three main sections.

• First, you come up with a really clever design on the computer.

• Second, you take the design and create instructions that describe how to carve it. This process is called CAM.

• Third, we need to hand these instructions over to the machine. This is usually done with a digital interface.

Computer-Aided Design (CAD)

In this section, we learn about CAD software and its importance in creating designs for CNC machines.

CAD Software Options

• Beginners can use simple 2D graphic programs like Inkscape or Illustrator.

• Programs created specifically for hobbyist CNC machines include CAMLab, Carbide Create, and Easel.

• Professional-level CAD programs like SolidWorks or Fusion 360 are also available.

Computer-Aided Manufacturing (CAM)

In this section, we learn about CAM software and its importance in creating instructions for CNC machines.

Creating CAM Instructions

• The first step when creating our CAM instructions is to define our material.

• Second, we need to choose our cutting tool.

• We can also define the speeds and feeds using cheat sheets found online.

Creating CNC Instructions with Fusion 360

In this video, we learn how to create instructions for a CNC machine using Fusion 360. We cover the process of defining material and bit info, writing the body of the instructions, exporting them in G-code format, and finally sending them to the machine.

Defining Material and Bit Info

• Define material and bit info before creating instructions.

• Material refers to what we're cutting while bit info refers to the tool used for cutting.

Writing Toolpaths

• Write toolpaths that tell software what shapes to cut out.

• Toolpaths are paths through space that our cutting tool follows.

• Achieving this differs from software to software but is easy in Fusion 360.

• Set up one toolpath for inner design and a 2D contour toolpath for outer shape.

Simulating Cuts

• Use CAM software to simulate cuts before sending them to the machine.

• This helps catch potential problems before plowing through material or breaking the machine.

Exporting Instructions in G-code Format

• Export instructions in a language that the machine can understand.

• Most machines read something called G-code which stands for Geometric.

• The software writes G-code automatically so there's no need to learn how to write it yourself.

Understanding G-code

• Having a basic understanding of G-code will help avoid unwanted problems as you get more into CNC machines.

• Put simply, G-code tells the machine where to travel by plotting points on a Cartesian plane.

• The code includes lines that plot each shape of the design based on toolpaths defined earlier.

Sending Instructions to Machine

• Send instructions from computer to machine using a control box that includes a microcontroller.

• Strap in material and place appropriate bit in the collet.

• Place machine in starting position manually and adjust router speed before hitting run button.

Avoiding Errors

• Most errors are caused by including features or settings without knowing it.

• Be careful to only include what you want the machine to do.

Conclusion

• If you're ready to dive into CNC machines, subscribe for more Fusion 360 CAM tutorials and CNC projects.