Introduction to PrusaSlicer
A Formidable Slicer
PrusaSlicer is Prusa Research’s high-powered entry in the 3D slicer market. Originally based on Slic3r by Alessandro Ranellucci, in 2016, Prusa branched off with their own in-house version, called Slic3r PE (Prusa Edition), which was released via GitHub.
As Slic3r PE departed more and more from the original software, Prusa officially renamed it in May 2019 to avoid confusion. Since then, PrusaSlicer has continued to develop and evolve, with updates every few months.
You don’t have to own a Prusa printer in order to benefit from this free and open-source program. Thanks to a rich support community, Prusa is now including printing profiles for many other manufacturers. The latest version also comes with greater SLA functionality, automatic variable layer height, and more.
In this article, we’ll be taking a look at how to begin using this slicer, give you an overview of some of the important and useful features, both basic and advanced, as well as where you can get support when you need it and some good alternatives. Let’s jump in!
Features at a Glance
Before really getting into the details, let’s give a quick snapshot of PrusaSlicer’s most notable features.
To start, thanks to the grouping of like settings, the slicer makes it very easy to customize and save various profiles. For example, a user can switch filament profiles without affecting printer settings. And with the over 110 premade profiles, its easy to get started creating your own.
Worried you’ll have to remember which highly-customized profiles you used with which project? Don’t be. PrusaSlicer allows you to save a 3MF file that stores all objects, settings, modifiers, and their parameters.
Other notable features:
- MSLA (resin) and multi-material support
- Smooth variable layer height
- Custom supports using modifier meshes
- Ability to “wipe” into infill
- Ability to repair models via Netfabb (only on Windows)
- 14 languages
In case you’re already familiar with PrusaSlicer, here are some of the coolest features that came with the latest 2.2.0 version:
- SLA hollowing
- Automatic variable layer height
- Adaptive elephant’s foot compensation
- Ability to insert pause or custom G-code at a certain height
- 3MF thumbnails when uploaded to the Prusa website
- ColorPrint for the MMU
PrusaSlicer has a clean look and feel. The various tools are distributed around the screen, and most can be controlled with keyboard commands.
The first time you open the program, PrusaSlicer will start the configuration assistant, which will guide you through selecting your printers and materials. Upon completion of the assistant, the printers and materials you selected will be accessible on the main screen.
If you’ve never used PrusaSlicer before, this is the quickest way to get your model sliced and ready to print:
- The main screen starts with a 3D view of your printer’s build plate. Import your model by clicking on the add icon on the top toolbar. Your selected model appears on the build plate.
- Manipulating your model on the build plate is simple. Changing the view is simply done by clicking and dragging. Rotation and scale tools can be exact with keyboard inputs or more organic with mouse control.
- Choose your printer, material type, and print settings on the upper right.
- Depending on your model, you can activate supports or add a brim just below the profile selections.
- Click the preview button and the application automatically slices your model, with export options in the lower right corner.
If you want to make more complex changes, there’s still much more to explore, so read on!
To best understand PrusaSlicer, there are a few fundamental aspects one should become familiar with: the two views, the three modes, and how to modify and save your settings profiles.
Note that this discussion primarily refers to the MacOS version of PrusaSlicer, although most details will be the same for the Windows version.
Once you complete the configuration assistant, PrusaSlicer opens to the 3D editor view. This is where you’ll do most of your preparation work. After importing a model, you have access to the movements, rotation, scale, and cut tools on the left side of the screen. Prusa refers to these tools as “gizmos”.
Along the top is a series of tools that enable you to duplicate objects and split multi-part objects, along with other operations. This is also where you can access the variable-layer-height tool. (More on that later.) On the right, you’ll see the main print-quality selection, the filament (or resin) settings, and your printer model (or models). You can change supports and the infill and brim settings, and the window just below shows an outline of imported objects along with any modifiers.
At any time, you can switch to the preview view. Doing so will automatically slice your model and give you a preview of the finished print. Here, you can change what’s displayed to give you a visual representation of things like volumetric flow rates, retractions, ColorPrint previews, and more. There is also a very useful window in the lower right that shows estimates of the cost, the print time, and how much filament will be used.
PrusaSlicer has three different modes for you to choose between, depending on your level of experience and the amount of tinkering you like to do. Settings are color coded depending on the mode they’re “unlocked” with:
- Simple mode, indicated with the color green, provides you with basic controls to get you started.
- Advanced mode, colored yellow, allows you to change some more complex settings.
- Expert mode, colored red, unlocks all settings and is designed for the most experienced users.
Settings are collected under three groups, each of which has its own screen: Print Settings, Filament Settings, and Printer Settings. Each set is accessed under its own tab, has its own profile, and collects specific settings into sections (e.g. “Support material”, “Speed”, and so on under Print Settings).
Whichever mode you choose, all of the settings remain color coded to signify their relative complexity. Additionally, if you hover over a setting, an explanation of the function will appear, so there’s usually no need to search through the online manual.
Once you change a default setting, the profile will change to “modified”, and you can save the profile to use the same settings again. You can always revert to the default setting by clicking the reverse arrow next to the setting.
Having done all this work to set up a print, wouldn’t it be nice if you could save it all? Well, you can! Just save the project as a 3MF file. It’ll contain all of the profiles, models, and settings just as they are.
Now that we understand the basics and have seen some of the impressive features PrusaSlicer is loaded with, it’s time to dig a little deeper into all the settings we can play with.
This screen has a number of sections you’ll need to define for every print job. Of particular importance are the following:
- Layers and perimeters: This grouping includes the basic settings behind aesthetic detail and quality.
- Infill: This collection has everything to do with infill.
- Support material: Apart from support settings, here’s where you can add a raft.
- Speed: A potentially overwhelming number of speed settings!
On this screen, you can adjust settings that depend on the filament in use. The most obvious are the extruder and bed temperatures, but you also have the option to tweak fan and advanced settings.
If you’re just starting out, there isn’t a whole lot you’ll need to change here. However, as you progress, you may want consider the following two settings:
- Retraction length: Helps with a number of print quality issues
- Lift Z (or Z-hop): Helps with dragging and stringing problems
The printer settings screen is also where you can insert custom G-code.
PrusaSlicer has a number of notable features beyond the standard slicing settings. This is where you can get very technical with your slicing, if that’s your thing.
One of the most powerful tools PrusaSlicer has is the ability to use modifier meshes. These are shapes created within the application that aren’t printed but affect settings for printed parts. These modifiers do things like block or enforce supports, adjust layer heights, change infill patterns or densities, and set specific numbers of perimeters.
Variable layer heights can reduce print times without sacrificing print quality. Previously, layers could only be manually adjusted, but now you can select automatic options that analyze the model and apply the best layer height settings. The tool essentially works by changing the layer height based on the shape of the model.
Another layer-related feature is adaptive elephant’s foot compensation. Elephant’s foot is that bulge you sometimes get in first layer. With this feature activated, you can adjust how much it shrinks the first layer to compensate for whatever effect you may be experiencing.
Inserting a pause or custom G-code at a certain height is a very useful feature. Pausing at a particular layer allows the user to, for example, insert a magnet into a hole or swap filament colors.
ColorPrint is a feature that originally provided a way to pause prints in order to manually swap filaments at a programmed layer height and show previews in the editor. Despite the MMU2S (Multi-Material Unit) now being available, ColorPrint is still a very popular and useful tool for single-extruder, non-MMU printers. The latest version of PrusaSlicer allows printers with the MMU to also access ColorPrint for enhanced functionality.
Now that Prusa is making its own resin printers, PrusaSlicer has some SLA functionality. Choosing the Prusa SL1 as your printer switches the interface to SLA mode, giving you access to several new tools, such as SLA hollowing and supports.
A useful tool is the “optimize orientation” option found when right-clicking on a model and opening the contextual menu. This analyzes the model for the best orientation for SLA printing.
The new hollowing tool gives you the ability to change wall thickness and add variable-width drainage holes, saving expensive resin when solid models aren’t necessary.
This feature allows automatic and manual supports to be generated. And while the SLA functionality is only meant for the Prusa SL1 printer, there is the option of exporting the supported model as an STL file, which can then be imported to some other SLA slicer, such as ChiTuBox.
Community & Company Support
Just like for the MK3S, Prusa Research provides excellent support with PrusaSlicer. The online knowledge base is extensive, from configuration and operation to all of the various settings. And if you can’t find the information you need, their user-based support forum is another option. You can search for and read other users’ questions, comments, and suggestions. You can ask your own questions, too, after signing up for a free account.
This support has extended beyond Prusa Research, as they now supply community-created profiles for several other 3rd party printers. This is in line with the Prusa ideology to keep things open-source and supportive of the greater 3D printing community.
To install 3rd party profiles, simply run the configuration assistant and select your printer. Current 3rd party models include the BIBO 2 Touch, the Creality Ender 3, the LulzBot Mini, and the LulzBot TAZ 6.
There are several good alternatives to PrusaSlicer. Some have different strengths or offer different functions, and most support a greater variety of printers. And while earlier versions were quite different from each other, the disparity between them is becoming less significant as they are all refined over time. Below are some key points about the major alternatives.
- Ultimaker’s Cura: Cura is perhaps the most popular slicer among the 3D printing community. It’s free, open-source, and powerful.
- Simplify3D: Simplify3D is the number one paid, professional, all-in-one slicer platform.
- ChiTuBox: The resin slicer scene isn’t as developed as that of FDM, but programs like ChiTuBox aim to change that. This free tool is capable and cross-platform compatible.