In most cases, it should be possible to conduct the 3D printing process without modifying any of the more advanced parameters (that are hidden by default) in Cura, as these parameters, for the most part, are reserved explicitly for more experienced users that would like to have complete control of their prints.
On the other hand, in some cases, the parameters considered to be advanced or expert-level by Cura are related to some of the core parameters that require configuration on a print-by-print basis, which makes it vital to have a good grasp of how the more advanced parameters operate since they will also require adjustments.
In today’s article, our topic will be one such parameter in Cura, known as the minimum extrusion distance window, which is one of the parameters that we can consider to be essential for retraction to work correctly, and as a result, one that requires precise configuration for a successful print, even though it’s an advanced parameter.
So, what is the purpose of the minimum extrusion distance window parameter in Cura?
The minimum extrusion distance window parameter in Cura determines the length of the filament that the Maximum Retraction Count parameter will apply to, with these two parameters combining to determine the maximum amount of retractions that can be performed on a particular portion of the filament.
In the upcoming sections, we will be examining the minimum extrusion distance window parameter of Cura in more detail, find out how to configure this parameter as optimally as possible for a successful printing process, and finally, go through the steps you will need to take to find and modify this parameter in the settings of Cura.
What Is Minimum Extrusion Distance Window in Cura?
Even though the name of the minimum extrusion distance window parameter does not reveal much about its actual definition, which does make it sound cryptic at first glance, the purpose of the parameter is actually pretty straightforward to understand.
The minimum extrusion distance window parameter in Cura is one of the two parameters that determine the maximum number of retractions that can take place during the 3D printing process, along with the maximum retraction count parameter, essentially allowing you to limit the number of retractions.
In a nutshell, the maximum retraction count parameter specifies the maximum number of retractions that can take place within a particular length of the filament, where this length is determined by the value of the minimum extrusion distance window.
When the two are combined, we obtain a clear rule that states only a particular number of retractions are allowed within a specific portion of the filament, with the 3D printer having to ignore any further retractions past this point.
For instance, in a case where the maximum retraction count value is set to 100 and the minimum extrusion distance window is set to 10 millimeters, the 3D printer is only allowed to perform 100 retractions on the same 10 millimeters of the filament, and any further retractions will not occur within the exact 10 millimeters once the count is hit.
Once the retraction performed 100 retractions ago becomes farther than 10 millimeters, which happens naturally as the 3D printing process naturally goes on due to more and more filament being extruded, a retraction is allowed again, following the same formula.
While limiting the number of retractions can seem unintuitive at first, especially considering that an insufficient number of retractions can easily lead to commonly encountered issues such as stringing and blobbing, performing too many retractions on the same piece of filament comes with problems of its own.
When the same portion of the filament is retracted over and over, the extruder gears eventually end up chewing the filament to a point where it becomes impossible for them to make contact with the filament correctly, causing the issue known as filament grinding, where the filament may either end up coming out in small chunks or not be able to move down at all.
As the occurrence of such a scenario will essentially cause print failure, limiting the number of extrusions through the minimum extrusion distance window and maximum retraction count parameters becomes essential for the success of the 3D printing process.
How to Configure the Cura Minimum Extrusion Distance Window Parameter Optimally?
As the minimum extrusion distance window will directly determine whether the 3D printer will be performing the retractions optimally or not, configuring it to be as precise as possible is one of the best things you can do to improve the quality of your prints.
We recommend configuring the Cura minimum extrusion distance window parameter the way that Cura suggests, which is to set it to be equal or close to the value of the retraction distance parameter, as this will ensure that the retraction count is refreshed enough to avoid filament grinding.
Once you configure the minimum extrusion distance, we recommend modifying the maximum retraction count parameter to perform further tuning if you’re facing issues related to the retraction.
In a nutshell, in cases where you’re facing issues related to the filament not being retracted enough, such as stringing and blobbing, increasing the maximum retraction count is what you will need to do.
On the other hand, in the exact opposite scenario, where the filament is retracted way too much, causing the problem of filament grinding, you will need to decrease the maximum retraction count value.
How to Find and Modify the Minimum Extrusion Distance Window Parameter in Cura?
Since the minimum extrusion distance window is a parameter that Cura considers to be expert-level, there will be an extra step you will need to take before you can find this parameter in the print settings section and apply the adjustments of your choice.
Below, you can find a step-by-step guide for locating and modifying the minimum extrusion distance window parameter in Cura:
- Click the Prepare tab on the top of the Cura window.
- Click the pane on the right to bring up Print Settings.
- Click the Custom button if you see it. Else, skip this step.
- Click the “three lines” icon next to the search input, and choose the All option.
- Type “minimum extrusion” in the search input and press enter.
- Input the desired value in the input labeled as Minimum Extrusion Distance Window.
Once you’re done adjusting the minimum extrusion distance window, remember to modify the maximum retraction count parameter value as well, since these two parameters work together to determine the number of retractions that can occur in a particular piece of the filament.
Even though the minimum extrusion distance window parameter has a very simple purpose, the fact that it has a significant impact on the health of the retractions that your 3D printer will perform during the printing process makes it a parameter that requires precise configuration.
To quickly recap, you can limit the number of retractions that your 3D printer performs during the printing process by configuring the minimum extrusion distance window parameter in Cura, which practically specifies the length of filament where the maximum retraction count value will be in effect.
Since too much retraction and too little retraction can both cause significant problems for the 3D printing process, it’s vital to configure the minimum extrusion distance window and maximum retraction count parameters in a balanced way where the number of retractions performed doesn’t cause issues on either end.
Mike started his 3D printing journey with the Anet A8 when it first came out back in 2017, and has been obsessed with 3D printers ever since. Nowadays, he primarily uses his Ender 3 to print functional parts that make his life more convenient whenever possible.