Software update: PrusaSlicer 2.6.0

Prusa Research has released a new version of PrusaSlicer. Simply put, this program ensures that a 3D design comes out of a 3D printer as best as possible. PrusaSlicer is open source and available for Windows, Linux and macOS. It is primarily developed for Prusa’s own printers, but includes a large number of profiles for printers from other brands. In version 2.6.0 we find improved tree supports and areas that need support are automatically marked. The complete changelog for this release can be found below.

Organic Supports
In this release, we are presenting our significantly improved implementation of tree supports, which we call ‘Organic supports’. We choose a new name for our supports because of their distinctively smooth shape and several differences in their behavior. Our implementation is an evolution of the tree supports by Thomas Rahm, which are significantly improved tree supports originally from Cura. We would like to thank Ultimaker Cura and Thomas Rahm for the effort they have invested into the problem.

In contrast to the previously common implementation of tree supports, the branching of our Organic supports is smarter and we made them straighter (shorter), smoother, and more stable. The cross-section perpendicular to the branch axis is guaranteed to be circular, and the algorithm automatically uses double perimeter walls for the trees where needed (this is configurable).

The Organic supports are easily removable, do not scar the surface, and are fast and cheap to print. Models can now be printed in orientations that were previously unthinkable (mirroring SLA printing capabilities) and supports for even the most complex shapes are typically easy to remove. Organic supports can be manually enforced or blocked using the Paint-on supports tool.

Automatic FDM Support Painter
PrusaSlicer now has an automatic painting tool for defining areas requiring supports, factoring in various aspects like the model’s center of mass, bed movement, potential extruder collision, material, and bridging. It can also automatically detect if a print requires supports and alert the user in the case they are not enabled.

Text embossing tool
The new Text tool lets you insert, manipulate, and edit text as a 3D object. This provides a convenient way to customize models and add elements such as notes, signs, or serial numbers directly in the slicer.

Texts can be embossed, debossed, or even used as a modifier. However, the tool even offers the ability to make the text follow curved surfaces. To change the text position, you can simply drag it on the object’s surface. The text editor automatically imports the font library installed on your device (all TrueType fonts should work).Even after closing the Text tool, the text remains fully editable. The same goes for re-opening 3MF project files. You can also create and save text styles to reuse them in future projects.

Improved Cutting tool
The Planar Cut tool has been available in PrusaSlicer for a long time. It is handy for preprocessing huge models that don’t fit the build volume or which are too complicated to print in one piece. With this release, we are extending its functionality.

You can newly cut the model at any angle. Defining the precise cutting angle can be done both by a 3D gizmo or by simply drawing a cutting plane by dragging the left mouse button while holding down the Shift key. If the cutting plane intersects the model in several different regions, you can select which parts to cut and which to keep connected by right-clicking on them.

You can select if the cut part should be placed on the bed with the newly created flat surface. You can also choose to keep the alignment of the parts, for example, for printing with a multi-tool printer.

Adding connectors and dowel pins
We understand how important it is to assemble the final parts together with an emphasis on precision and simplicity. That’s why we added an option to define various types of connectors. You can control the depth, size, and tolerances of each connector and the negative hole.

Measurement Tool
PrusaSlicer now includes a measurement tool for gauging distances between vertices, edges, and planes. You can also use it to measure angles, and to scale objects uniformly by editing the measure distance.

Dynamic overhang speed (and dynamic fan speed on overhangs)
This feature lets you slow down the print speed when printing overhangs, which enables better cooling when it’s needed. The algorithm calculates extrusion overlap with the previous layer and applies speed calculated from the overhang slowdown function. Users can control the shape of the overhang slowdown function via four input points – each point has an extrusion overlap value expressed as a percentage of the full width, and desired speed on such overlap. The speeds in between the control points are calculated via linear interpolation.

Likewise, users can create custom fan speed curves, so that extreme overhangs get increased cooling. Of course, with some polymers, too much cooling will negatively impact the mechanical properties.

Extending sparse infill
A long-standing issue was connected to bridging solid infill printed over sparse infill. The shape of such infill islands was only determined by what was above, and the infill lines were often inadequately supported as a result, leading to mid-air extrusions and possibly failed prints. PrusaSlicer now extends the lines of the bridge infill so that their ends are supported by the sparse infill on the layer below. The bridge infill is now always using ‘Thick bridges’. The new algorithm works for all infill types. The comparison image below shows exactly the same model (a cube with a counterbored hole in the top face).

Improved ensure vertical shell thickness

PrusaSlicer 2.6 improves the handling of vertical shell thickness on scraping surfaces. Previous versions used rectilinear infill to address thinning walls and potential holes in steeply sloped areas. The latest version now identifies regions where short rectilinear lines could cause vibrations and surface artifacts, replacing them with a concentric infill. This method often leads to 10-15% shorter print times without compromising quality.

Other new features

• Option to avoid crossing curled overhangs
• Exporting STL objects with boolean operations
• Assigning tool heads to different features
• Idle temperature settings for multi-tool printers
• Wipe tower stabilizing cone
• One-click import from Pritables.com
• Template filament profiles
• New experimental support for SLA
• One-file vendor profile enables adding new printers without a new PrusaSlicer release
• G-Code thumbnails can now be exported in JPG and QOI formats
• SLA hollowing is now up to 10x faster
• SLA time estimate is now more accurate for the Original Prusa SL1S Speed
• New and updated 3rd party printer profiles
• Arrange’ and ‘Fill bed with instances’ functions now take into account skirt and brim
• More intuitive Klipper firmware support
• Opening 3MF files now gives the option to import the geometry only
• New “PrusaConnect” host type with pre-filled URL
• It is newly possible to set acceleration separately for external perimeters, solid infill and top solid infill
• ‘Set Number of Instances’ now works when multiple objects are selected
• Optional scrolling to mouse cursor rather than screen center