How to Use Post Processing Scripts in Cura? (Detailed Guide)

With its ever-expanding toolkit that makes life much easier for 3D printing enthusiasts, Cura is easily the first software that comes to mind whenever we think of slicers.

Alongside the large array of parameters you can fine-tune to take your prints to the next level, Cura offers even more ways to improve the printing process through scripts and plugins, which allow you to add extra, custom features to the slicer.

Today, we will be focusing on the post-processing scripts functionality in Cura in particular, which is one of the quickest and most effective ways of implementing a piece of custom functionality to your slicer software for regular usage.

So, how to use post-processing scripts in Cura?

To use post-processing scripts in Cura, click the Extensions tab on the top menu, bring your mouse over to the Post Processing option, and click the Modify G-Code that appears as a result.

Press the Add a Script button in the dialog that pops up, choose the post-processing scripts you would like to use to activate, and configure it through the pane on the right.

In the upcoming section, we will go into greater detail about post-processing scripts in Cura and explore the more advanced features it offers, such as implementing your own custom scripts into Cura.

How to Use Post Processing Scripts in Cura?

Since the post-processing scripts feature can benefit beginners and more advanced users alike, let’s start with the rudimentary usage of post-processing scripts first.

Here are the steps you can follow to use the built-in post-processing scripts in Cura:

  1. Click the Extensions tab on the top menu of Cura.
  2. Bring your mouse over the Post Processing tab.
  3. Click the Modify G-Code tab that pops up to the right.
  4. Click the Add a Script button, and choose the script you would like to use from the list.
  5. Configure the script through the parameters on the right pane.

By following these steps, you can activate and use the post-processing scripts Cura comes with, but the extent of this feature doesn’t end there.

In fact, the best thing about the post-processing scripts feature is that it allows you to implement custom scripts; specifically tailored to fit your needs.

Here is how you can add your custom scripts to Cura:

  • Download the post-processing script you would like to add or write your own, which should be a Python script (.py file).
  • Copy the script file to the scripts directory of Cura, located in \AppData\Roaming\cura\scripts for Windows.
  • Restart Cura.

The next time you open the post-processing scripts dialog up, you should see your custom script in the list when you press the Add a Script button.

Please note that the scripts you would be downloading are community-made, meaning that they are essentially 3rd party, and not supported by Ultimaker.

As a result, we only recommend downloading (or writing your own) scripts if you are an advanced user who has experience with reading and writing Python code to ensure that the scripts aren’t malicious in any way.

What Are Post Processing Scripts in Cura?

There is no denying that post-processing scripts come in handy in many scenarios by providing features that contribute to the printing process, usually in the quality-of-life department.

In a nutshell, post-processing scripts are pieces of code that read the G-code Cura produces when it slices the model and modify it with the functionality they offer before Cura sends the final output to the printer.

For instance, a simple example of a very functional post-processing script would be a piece of code that pauses the printing process at a certain height.

To explain in a very simple way, the method such a script would use is to read all the G-code lines, detect the G-code where the printer would be reaching the desired height, and add a pause G-code, such as the M0 (Unconditional Stop) command.

Since it’s possible to read the entire G-code and modify the existing G-codes or add any G-code you wish, it’s practically possible to implement any feature that the printer allows through post-processing scripts.

To write your own post-processing scripts, all you need to do is get yourself familiar with G-code and learn the Python programming language – one of the most popular programming languages right now with many sources (and a great community) you can use to learn.

Cura Post Processing Scripts Not Working – What to Do?

In some cases, it’s possible for some post-processing scripts not to behave the way you intended or not display any behavior at all despite being active.

The most common reason behind Cura post-processing scripts not working is an incompatibility between the G-codes the script utilizes and the G-codes your printer recognizes.

As there is no standard for G-code to ensure that all firmware supports the same G-codes, there are situations where a script may work for one firmware but not for the other.

For instance, let’s think of a script that adds the M701 G-code to trigger a filament load when the printer reaches the desired layer.

As the M701 G-code is only compatible with some firmware, such as Marlin and RepRapFirmware, a printer that runs on a firmware that doesn’t support this G-code (such as Repetier) will ignore this G-code or throw an error.

If you have experience with the Python coding language, you can most likely find out the G-codes the script utilizes and modify them in a way that would work for the firmware of your printer.

Wrapping Up

While the real strength of the post-processing scripts feature is more leaned towards advanced users, the fact that Cura comes with some practical scripts out of the box also makes it a fantastic feature for beginners.

To quickly summarize, you can navigate to the post-processing scripts dialog in Cura by navigating to the Extensions menu on the top bar, bringing your mouse over the Post Processing menu item, and clicking the Modify G-Code menu item that pops up.

Within the dialog, you can use the Add a Script button to choose the script you would like to use from the menu and use the parameters on the right pane to configure it.

Happy printing!