3D Printer G-Code- Everything you need to know

 |  Michael Gorman

All You Need to Know About 3D Printer G-Code

Many people use 3D printers without actually knowing that they have a language of their own. The 3D printers that are being made these days have a programmed language that is numerically controlled. It consists of a set of commands or instructions, which are known as G-codes. After a model is designed, it has to be broken down into a format the 3D printer understands. These commands are what make up the G-code.

The reason that these commands are known as G-codes is because they start with ‘G.’

What is a G-Code?

A G-code is the printer’s language, which humans use to communicate with the machine and tell it what to do, and how to do it. There is a command within the G-code that makes the printer move its part within the system. There are also the G-commands and the M-commands within the G-code that have assigned actions or movements to them.

The commands within the G-code tell the 3D printer what kind of actions it should perform. What temperatures to set, the speed it should use, where to move, etc. Having basic G-code knowledge is very beneficial to all makers. It gives them a better understanding of the workings of the 3D computer. Also, they can use it to verify their print files, perform machine maintenance, and debug as well.

While G-code is the standard language for 3D printers, they may also use other commands or formats. If the file format for your printer is different such as the .x3g file, it can be exported to another location. This is very important because many other file formats are just binary files. You can read them more easily when you view it in a G-code file rather than the binary form with plenty of 0s and 1s.

How does G-Code work?

Ideally, you would not need to write a G-code. Your slicer program does this automatically by converting the designed STL file to a G-CODE, which is then used by the printer. As the name implies, the slicer is responsible for slicing the model in the XY plane. Each of the slices will stand for one layer that the printer is expected to print. From the generated G-codes and M-codes, the printer is informed on how to extrude the plastic and where to deposit it.

You can also write the G-code for the printer yourself. To do so, you will have to use a text editor with the output file being.TXT. After writing the file and saving it, all you need to do is to rename it so that the suffix has the G-CODE in it. There are some coding editors (mostly used by C++ developers and Java developers), which can come in handy for writing the G-code, but the notepad might be the only thing you'll need since you'll not be writing more than some short G-Code lines.

How to generate G-code?

There is a lot of information in the G-code. You might be able to read it if you open it with a text editor, but it's improbable that you will make any sense of it. To better understand the G-code, you can use a program like the Repetier Host. With a program like this, you will be able to open the G-code and see all the paths that the print head will follow to make the print. Colors in the Repetier Host indicate the code functions

To generate the g-code automatically, you’ll need a slicing program or a 3D modeling software with an in-built slicer like SelfCAD. Another popular slicer to use is Cura. There are thousands of movements involved in printing, and the g-code can be as long as hundreds of pages. Depending on its length, it might take from tens to hundreds of hours to write all of the code manually.

With SelfCAD, all you need to do is click on the 3D Print in the main toolbar. It will redirect you to the slicing software, which is all that you need to generate the G-code and then save it on your computer. The whole process of producing the G-code is automated with the slicing programs.

To generate the G-code, the slicer combines different commands. They set up the sequence for the movement, temperature, and extension that will print the 3D model.

How to convert STL to G-code?

It's a long process to convert STL to G-code. Here are the key steps for converting STL to G-codes:

Step 1: Get a conversion tool. 

SelfCAD is a very appropriate tool to use for slicing. It's browser-based, so you don't have to download it, and it is in-built into a 3d modeling software.

Step 2: Download or design a 3D Model for the printer to print

If you’ve already designed a 3D model, and you are looking to print, be sure that when exporting the model, and save it in an STL format. Alternatively, you can also download models from sites like Thingiverse, Myminifactory, and Cults3d.

Step 3: Select/add the 3D printer to the slicer

First, you'll have to choose your printer in the slicer. If you won't find your printer you can add it yourself. Check out our article on how to add your 3D printer to SelfCAD slicer to learn how to do it. But before you print, you'll have to set up the settings for the print.

This is quite simple to achieve through: go to preferences on your screen and click on the printer you can add it yourself. Check out our article on how to add your 3D printer to SelfCAD slicer to learn how to do it.

Step 4: Open the STL file, then prepare the settings for the printer

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The next step is to open or import the STL file and place it on the printer's bed and adjust its position. Then, after selecting the material for the print and adjusting the settings of the print, you're almost good to go. Just set the support for the print and bed adhesion before continuing.

5. Slice the part to get the G-code to print

After you have configured all the settings, click on the ‘Slice’ button. The slicer will show you a preview based on your settings. 

You will also get an estimated weight based on the materials you selected and the print time. 

If you are not yet a pro in 3D printing, take your time to look through the preview and play the simulation before actually printing it. This will allow you to see little things that need adjustment and correct them before printing. You can watch our video tutorial to learn more about slicing in SelfCAD. https://bit.ly/30IfG0a.

Do you want to learn 3D modeling? Check out our interactive tutorials.

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About the Author

Michael Gorman is a highly skilled freelance writer and proofreader from the UK who currently works at best paper writing services. If you need the best essay, he’s the best essay writer for you. Being interested in everyday development, he writes various blog posts and discovers new aspects of human existence every day.


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