Z offset is the parameter responsible for determining the gap between the nozzle of the 3D printer and the build plate, which makes it play a vital role in the success of the printing process due to the direct impact it has.
On the other hand, since Z offset isn’t a value that needs frequent optimization, getting it right the first time will bring fantastic improvements to your 3D printed models for the small amount of time and effort you will need to spend on configuring it.
In this article, we will analyze the Z offset parameter and how you should configure it while printing with PETG filament, in particular, as the Z offset requirement of PETG is quite different than the Z offset requirement of PLA.
So, what is the optimal Z offset value for printing PETG?
We recommend increasing the Z offset value by another 0.02 to 0.05 millimeters while printing PETG, as, unlike PLA, PETG doesn’t print well when it’s squished onto the build plate.
The increased Z offset value will create the necessary gap between the nozzle and the build plate, giving PETG enough space to avoid issues such as plastic gathering on the nozzle.
In the upcoming sections, we will analyze the relationship between the Z offset value and PETG filament in better detail, discuss the effects of different Z offset values on printing PETG, and outline how you can set the Z offset in Cura.
What Is the Optimal Z Offset Value for Printing PETG?
As Z offset is one of the more critical parameters that can easily make or break the printing process, configuring it as optimally as possible is one of the first things you should do while printing PETG.
To configure the Z offset value as optimally as possible for PETG, add an extra 0.02 to 0.05 millimeters to the Z offset value you already use for printing PLA.
Doing so will be helpful to combat commonly encountered issues while printing with PETG, such as plastic accumulating on the nozzle and holes appearing on the print by giving the plastic enough room to settle on the model instead of being dragged away by the nozzle.
If you are unsure whether your Z offset value is correct, to begin with, start by calibrating the Z offset first by using the paper method and then add the extra millimeters on top of the value you have found.
As the optimal value depends on the printer and the filament you use, experimenting with a few test prints while incrementally changing the value based on the observations you make is the best way to ensure that you configure the Z offset as correctly as possible.
What Are the Effects of Z Offset on Printing PETG?
Understanding if you have configured the Z offset correctly is all about observing the signs that an incorrect Z offset value can cause, which is why we will take a look at how different Z offset values can affect your model.
To start, let’s talk about the effects a Z offset value that is too high can cause.
A Zoffset value that is too high while printing with PETG will cause adhesion between the model and the bed to be weak due to the pressure the plastic applies to the build plate being too low.
Alongside the primary issue of bed adhesion, you may notice print lines being too rounded, gaps on the first layer due to the infill not reaching, and deformation of the first layer.
Now, let’s look at the signs that would come out due to the Z offset value being too low.
A Z offset value that is too low while printing with PETG will cause the plastic to stick way too strongly to the build plate, making it extremely difficult to remove.
Issues such as the first layer having peaks and valleys, print lines being too flat, and inconsistencies in the first layer (including parts of the layer not being printed at all) are also signs that the Z offset value is too low.
We recommend observing the printing process to identify these issues, incrementally decrease or increase the Z offset value, and run more test prints until the problems are non-existent to find the most optimal Z offset value possible.
How to Set the Z Offset Value for PETG in Cura?
While Cura does not support setting the Z offset value through the print settings like it does many other parameters, there are two alternative methods you can follow to configure Z offset easily for printing PETG.
Configuring Z Offset in Cura with G-Code
Configuring the Z offset in Cura with G-code is the more advanced method, but it comes with the advantage of not needing to download any extra plugins.
Here are the steps:
- Find out the G-code responsible for setting the Z offset for your printer’s firmware. For instance, M206 would be the command to use if your printer runs on the Marlin firmware.
- Click the Settings button located on the top menu of Cura.
- Hover over the Printer option, and click the Manage Printers option in the dropdown menu.
- Choose your printer from the left pane, and click the Machine Settings button located on the right side.
- Scroll down to the end of the Start G-Code input box (located on the left bottom).
- Enter the G-code responsible for setting the Z offset and the value you would like to set the Z offset (refer to the firmware documentation to ensure that you use the correct syntax) to and close the dialog by clicking the Close button.
If this method proves too technical, an easier way to do this configuration is to use a plugin, which is our next topic.
Configuring Z Offset in Cura with Plugins
Configuring the Z offset in Cura with a plugin is as simple as it comes, as the plugin adds the Z offset parameter to the Print Settings section of the slicer.
Here is the step-by-step guide:
- Launch Cura.
- Add the Z Offset Setting plugin to Cura from the Cura Marketplace.
- Cura will ask you to sync the settings with a pop-up, which you need to follow to initiate the installation process.
- After the installation is complete, restart Cura for the plugin to become active.
- Navigate to the Print Settings section (click the Prepare tab, and click the rightmost pane below).
- Click the three lines icon next to the search input, and choose All from the dropdown to make the Z offset parameter visible.
- Type “z offset” into the search input, which will display the Z offset parameter.
From now on, the Z offset parameter you have selected will be active for all of your prints with the PETG material profile.
As Z offset is a value that does not require frequent tuning, ensuring that it’s correct the first time you print with PETG filament will go a long way in improving the quality of your 3D printed models.
To quickly recap, we recommend adding an extra 0.02-0.05 millimeters to the Z offset value you already use to compensate for the extra space PETG requires to print without issues, as PETG isn’t a type of filament that prints well when it’s squished.