How to Send G-Code to a 3D Printer

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The programming language used in 3D printers is known as G-code. Therefore, if you want to learn how to make use of your 3D printer effectively, you need to understand this programming language.

​Consequently, you will be in a better position to know how to control all aspects during the printing process, how to best troubleshoot your printer, as well as the early identification and prevention of failure before they occur.

​This numerically controlled language consists of a series of commands that are referred to as G-Code, with most starting with the letter G, thus the name. However, there also are other commands that carry out machine-specific codes that begin with M. Moreover, whereas G-code is the standard programming language on most 3D printers, other devices may make use of different commands or file formats.

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If you are looking to learn how to send G-Code using your 3D printer, read through this article to have a better understanding of how to do this correctly.

How do you send or edit G-code commands?

When using a machine that accepts standard G-Code files such as many RepRap devices, then an excellent method of testing the different commands is by sending them one by one manually.

Consequently, you need to assess how well your 3D printer is responding.

All this is possible from the Simplify3D by heading to the Tools and then Machine Control Panel. Once you are in the Machine Control Panel, confirm that you are linked to your 3D printer. After that, send your 3D printer G-code command using the Communications tab.

To do this, you essentially need to input the command you want at the window’s bottom and then to press the Send button. Moreover, you can always reboot your 3D printer to restore the machine to its original state or stop its actions if you wrongly send a G-Code command.

After you become conversant with all the commands, you may feel the need to repeatedly carry out an identical series of commands either after or before every print. Fortunately, you get the option to customize routines carried out at the start and end of every print. Therefore, to ensure your 3D printer performs all its actions automatically, you have the option to update your settings by clicking on “Edit Process Settings” and then choose the Scripts tab.

On this tab, you will find numerous scripts that you can edit, with each used at a different time when you are printing. For instance, you should only make use of Ending script at the end of your print, whereas the Starting script should be used at the very start.

Furthermore, Simplify3D comes with a default profile for your 3D printer, which includes scrips that have been tested and verified. Thus, you should use this as a reference point as you get to learn how to send G-Code to your 3D printer.

Every single time you adjust any script, you need to run a quick print test to confirm that your 3D printer behaves as expected. Subsequently, you can save these new settings permanently on Simplify3D’s profile management system for future use. Additionally, if you want to monitor all the changes you have made all through, you can set up numerous profiles.

Four G-Code commands to use with your 3D printer

Liner Movement – G1

This is an essential command to learn as it possibly accounts for up to 95% of all the G-Code files. The role of this command is instructing your 3D printer to move in a straight line towards a specific location. Moreover, you can either use this command to run multiple axes or a single axis simultaneously.

Nevertheless, you need to remember that the extruder is controlled similar to all the other axes. Therefore you can retract or extrude the filament from the nozzle using this command.

Set Positioning Mode – G90 and G91

The positioning of your 3D printer can either be relative or absolute. You should make use of relative positioning when instructing the printer how far from the current position it needs to move. In contrast, absolute positioning directs it to move in a precise XYZ coordinate.

Therefore, when looking to tell you’re your 3D printer to utilize relative positioning, send the command G91, and G90 for absolute positioning. Most of your G-code files will make use of absolute positioning because the slicer has already established a specific XYZ coordinate.

Nevertheless, you should use relative positioning when you wish to move the head for a particular distance along the axis or if you are uncertain of your head’s previous position.

Perform Homing Routine – G28

It is a command which instructs your 3D printer to carry out its homing sequence, and will then transfer the tool head to the device’s far edges up to a point it comes in contact with the end stops found that position.

It is with this command that many of your print files start, thereby ensuring your 3D printer begins from a specified position. Furthermore, this command is also useful in hastily moving one axis from causing any obstruction, and this is beneficial during the print end as it allows you to take out your part.

Set Current Position – G92

You should use this command when setting your axes’ current position, and this is vital when looking to offset or adjust any of your axes’ location. It is with your E axis, that is, the filament position that this command is used frequently.

Additionally, you can choose to override the present filament position hastily, thereby setting all the future commands are now relative to the current value. You can do this either immediately before a retraction or prime command or at the beginning of every layer.

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In conclusion, you now have an idea of what is a G-code as well as how to send a G-code to your 3D printer. Furthermore, you also have known of some of the G-Code commands you can use to ensure you have an excellent grasp of the 3D printing technology. Therefore, you now are in a better position to make use of your printer to create unique and high-quality 3D models.

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