Due to their role in preventing issues like stringing, blobbing, and oozing, retraction settings are some of the most significant values to configure correctly to ensure that the printing process goes as smoothly as possible.
As the optimal values for retraction settings show differences among different filament types, it’s not always easy to get the settings correctly from the get-go, especially if you are using a filament for the first time.
Today, we will look at the optimal retraction settings for PETG filaments in particular, as more and more 3D printing enthusiasts are making the switch from PLA filaments to PETG filaments with each passing day.
So, what are the best retraction settings for PETG?
While the optimal retraction settings for PETG depend on your printer, here are some values you can use to start experimenting with to find the optimal configuration that works for you.
- Retraction Speed – 20-30 mm/s
- Retraction Distance – 2-7 mm (shorter for direct drive, longer for Bowden)
- Retraction Minimum Travel – 1-2 mm
In the upcoming section, we will discuss both retraction speed and retraction distance in greater detail and explain the reasoning behind the values we have just mentioned and how you can further optimize these values for the printer you’re using.
What Are the Best Retraction Settings for PETG?
Finding the optimal retraction settings for the filament and the printer you use is one of the more challenging things in 3D printing, as it requires a decent amount of effort and time spent on experimentation.
As the optimal values for retraction speed, distance, and minimum travel for PETG vary between printers, let’s start by diving into how the retraction speed parameter works first.
Retraction speed determines how quickly the printer retracts the filament from the nozzle.
We recommend a retraction speed between 20 mm/s and 30mm/s for PETG.
It’s best to keep the retraction speed as closely as possible to the top of this range as retraction speed also affects print speed, which is why we recommend starting at 30mm/s, and gradually moving down in 1mm/s increments if you experience issues such as gaps or filament breakage.
Now, let’s do the same thing for retraction distance.
Retraction distance is the distance value for how far back the printer will retract the filament from the nozzle.
For using PETG filament with direct-drive extruders, we recommend a retraction distance of 2 to 4 millimeters.
On the other hand, with Bowden extruders, a value between 5 to 7 millimeters is optimal.
As a rule of thumb, the retraction distance should never be greater than the length of the nozzle, as such a value is almost guaranteed to cause issues.
Finally, let’s take a look at retraction minimum travel.
Retraction Minimum Travel
Retraction minimum travel decides the minimum distance of a travel move that will trigger a retraction.
We recommend a retraction minimum travel distance of 1 mm to 2 mm for PETG filament.
Once again, keeping this value as high as possible is optimal to refrain from unnecessary retractions, which will slow the printing process down.
By starting with a 2 mm retraction minimum travel distance and moving down in increments of 0.1 mm, you should be able to find the optimal value after some experimentation.
Configuring PETG Retraction Settings in Cura
Configuring retraction settings for PETG filament in Cura is mostly a breeze, thanks to Cura’s intuitive and easy-to-use interface.
Here is a step-by-step guide for configuring retraction settings in Cura for PETG filament:
- Click the Prepare tab on the top menu of Cura.
- Click the middle panel, where you can see the currently selected filament and nozzle size.
- Click the Material dropdown menu, and choose Generic PETG.
- Click the rightmost panel to bring up Print Settings, and hit the Custom button (not necessary if you’re already in Custom mode).
- Type “retraction” into the search box to bring up all settings related to retraction.
- Click the icon next to the search box, and choose All from the dropdown menu to make all print settings visible.
Following these steps will set your active filament to PETG and allow you to configure retraction settings for it.
Alongside the three main retraction settings we have talked about (retraction speed, distance, and minimum travel), Cura offers a few additional retraction-related settings you can configure, which we have listed below:
- Retraction Extra Prime Amount
- Maximum Retraction Count
- Z Hop When Retracted
- Minimum Extrusion Distance Window
Configuring PETG Retraction Settings in PrusaSlicer
Adjusting the retraction settings for PETG filament in PrusaSlicer is also a straightforward task with how easy the slicer’s user interface is to navigate.
Here is a step-by-step guide for configuring retraction settings in PrusaSlicer for PETG filament:
- Click the Plater tab on the top of the PrusaSlicer window.
- Choose Generic PETG from the Filament dropdown on the right pane.
- Click Printer Settings from the top of the window.
- Click Extruder 1 (you will have to configure each extruder separately if you have multiple) from the left pane.
Following these steps will make PETG the active filament and bring you to the menu for configuring retraction settings.
PrusaSlicer also offers a few additional retraction settings you can use to optimize the retraction process further:
- Detraction Speed
- Retract on Layer Change
- Extra Length on Restart
- Wipe While Retracting
- Retract Amount Before Wipe
What Happens to PETG With Too Much Retraction?
While it’s a widely known fact that too much retraction can cause PETG to cause stringing and blobbing due to the excess filament that oozes from the hotend, the opposite scenario isn’t talked about too often.
In a nutshell, too much retraction will prevent the printhead from extruding the correct amounts of PETG, which will cause the model you print to have gaps due to under-extrusion.
Since the printhead pulls the filament back during the retraction process, too much of a pull would mean that the filament won’t be able to make its way to the nozzle on time.
Because of this, arbitrarily setting the retraction settings to levels that are too high isn’t the solution to your problems with stringing and blobbing due to the simple fact that it will cause a whole new set of problems.
It’s undeniable that getting the retraction settings right is vital for a successful 3D printing experience no matter the filament you’re using, and PETG is no exception to this.
While it’s true that finding the optimal retraction settings that will yield the best results depends on a lot of factors that require experimentation on your side, there is no way around it if you want your models to be free of issues like stringing and blobbing.
We hope that this has been an informative read, and we will see you next time!