PrusaSlicer 2.9.2

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Summary

This is the final release of PrusaSlicer 2.9.2. It is functionally equivalent to 2.9.2-rc2, except for an update in translations.

Please, read change logs of 2.9.2-rc1 and 2.9.2-rc2 to see all changes with respect to 2.9.1.

When you first run the final build, it will search for all configurations produced by alpha or beta versions and offer to create a copy of the latest one.

Translations

• Updated Finnish translation (#14412, thanks to @J3r0github)

Linux build is now distributed through Flathub. Please see the respective page on our Prusa Knowledge Base for instructions.

PrusaSlicer 2.9.2-rc2

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Summary

This is the second release candidate of PrusaSlicer 2.9.2. Please, read the change log of 2.9.2-rc1 to see complete list of improvements and fixed with respect to 2.9.1

The release candidate uses the regular PrusaSlicer configuration folder.

Changes with respect to 2.9.1-rc1

• Fixed incorrect shortcut mentioned in the shortcuts list available from the SLA support points tool.
• Internal changes in the built-in downloader.

Translations

• Updated POT.
• Updated CS, PL, DE, IT, ES, FR, JA dictionaries.

Linux build is now distributed through Flathub. Please see the respective page on our Prusa Knowledge Base for instructions.

PrusaSlicer 2.9.2-rc1

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Summary

This is the first release candidate of PrusaSlicer 2.9.2. It mostly fixes bugs found in 2.9.1.

The release candidate uses the regular PrusaSlicer configuration folder.

Improvements with respect to 2.9.1

• When importing STEP files, the geometry is converted into triangulated mesh which PrusaSlicer internally works with. The triangulation is performed with some defined precision - higher precision results in higher memory requirements and slower slicing, but the triangulated mesh is closer to the geometry that the STEP described. Until now, PrusaSlicer used some hardcoded defaults. In this version, there is an extra dialog shown during STEP file import, where the required quality of the triangulation can be selected. Last used selection is kept and the dialog can be dismissed for good by the "Remember my choice" checkbox. However, there is an option in Preferences -> Other to start showing it again.

Bugs fixed with respect to 2.9.1

• Fixed a crash in the new SLA support points generator.
• Fixed freezing in the new SLA support points generator (possibly fixing #14281).
• Scarf seams were not generated at all in certain cases (#14278).
• Fixed two distinct cases of incorrect function of the sequential arrange / test feature, both resulting into extruder possibly hitting a previously printed object (#14298, #14304).
• Fixed a crash in the sequential arrange algorithm happening in rare cases when multiple instances were present.
• Fixed input data for sequential arrange XL and CORE ONE (#14354), improved precision for MK4S so the arrange is not too conservative.
• Fixed tolerance-related issue in sequential arrange test, sometimes causing rejection of valid object positioning.
• Fix a crash when loading invalid STL file (very old bug) (#14343)
• Fixed measurement of distance between parallel-aligned circles (#14360).
• Fixed inadvertent rejection of 3MFs containing only configuration and no geometry.

Translations

• Updated POT
• Updated CS, PL, DE, IT, ES, FR, JA dictionaries.

Linux build is now distributed through Flathub. Please see the respective page on our Prusa Knowledge Base for instructions.

PrusaSlicer 2.9.1

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Summary

This is the final release of PrusaSlicer 2.9.1. It is functionally equivalent to 2.9.1-rc2.

Please, read change logs of 2.9.1-alpha1, 2.9.1-beta1, 2.9.1-rc1 and 2.9.1-rc2 to see all changes with respect to 2.9.0. You can also check our blog article to get the summary.

When you first run the final build, it will search for all configurations produced by alpha or beta versions and offer to create a copy of the latest one.

Linux build is now distributed through Flathub. Please see the respective page on our Prusa Knowledge Base for instructions.

PrusaSlicer 2.9.1-rc2

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Summary

This is the second release candidate of PrusaSlicer 2.9.1. This release fixes two bugs found in 2.9.1-rc1.

The release candidate saves its profiles into regular PrusaSlicer configuration directory. When you first run it, it will search for all configurations produced by alpha or beta versions and offer to create a copy of the latest one.

Changes with respect to 2.9.1-rc1

• Test of sequential printability reported names of the colliding objects incorrectly in certain cases (the test itself was correct). #14238
• Fixed freezing of the new SLA support points generator in certain cases.
• In very rare cases, the new SLA support points generator was crashing. These cases are now detected and an error message is shown instead.

Linux build is now distributed through Flathub. Please see the respective page on our Prusa Knowledge Base for instructions.

PrusaSlicer 2.9.1-rc1

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Summary

This is the first release candidate of PrusaSlicer 2.9.1. This release is basically equivalent to 2.9.1-beta1.

The release candidate saves its profiles into regular PrusaSlicer configuration directory. When you first run it, it will search for all configurations produced by alpha or beta versions and offer to create a copy of the latest one.

Changes with respect to 2.9.1-beta1

• Linux Flatpak build uses a different runtime version to hopefully mitigate issues with some dedicated GPU cards. #13945

Localization

• Updated CS, PL, DE, IT, ES, FR, JA dictionaries.

Linux build is now distributed through Flathub. Please see the respective page on our Prusa Knowledge Base for instructions.

PrusaSlicer 2.9.1-beta1

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Summary

This is the first beta release of PrusaSlicer 2.9.1. This release introduces new algorithm for generation of SLA support point and couple of bugfixes.

To let you enjoy the beta without worries, the beta builds save their profiles into PrusaSlicer-beta directory, so you may use the beta side by side with the current release without ruining your production configuration.

New SLA support point generator

We are introducing a brand new SLA support spot generator, which replaces the existing solution and provides more precise and predictable support placement. The new algorithm better differentiates the areas requiring support – small, medium, and large islands, as well as overhangs – and adapts the support strategy accordingly.

• Small islands are supported by a single point placed at their center of mass.
• Medium islands use the Voronoi diagram to optimally place two or more supports.
• Large islands are divided into thin and thick sections, where supports are placed either along the central axis or around the perimeter for greater stability.
• For detected overhangs, the algorithm dynamically adjusts the support density based on Z height and overhang angle, minimizing unnecessary supports and ensuring even distribution.
  

The new algorithm is not randomized and it produces same results when given the same input repeatedly. In general, it is a great improvement over the old algorithm, which often failed in a spectacular manner even in seemingly very simple cases:

Additional changes make it easier to manage supports and enhance visual feedback:

• Support density can now be adjusted with a single slider – moving it instantly updates the preview, enabling smooth and quick fine-tuning.
• A new toggle for displaying the support structure allows users to hide or show the entire support construction for better model visibility.
• Manually added points are no longer ignored – when the user presses Automatic Support Generation, the algorithm considers them and adjusts the surrounding support density accordingly.
• Support types are color-coded, distinguishing islands, manual edits, and overhang supports.

Bugs fixed with respect to 2.9.1-alpha1

• CLI options export_sla and export_gcode were reintroduced after they were erroneously removed in 2.9.1-alpha1.
• When sending multiple beds to Connect, PrusaSlicer allowed characters in the filenames that Connect would refuse. This is now fixed and the names are refused immediately.
• Remove an extra 1.5s pause after toolchange on an XL printer. This pause has a meaning for MK4, but including it for the XL makes no sense and could lead to issues. #13987
• Fixed Compare presets dialog, which did not correctly filter presets when the user changed selection.
• The new option to propagate thumbnails from 3MF to the G-code when using CLI was rescaling the images incorrectly and they ended up stretched. Images are now cropped to prevent this from happening.
• Scarf seams are now suppressed on the first layer to prevent adhesion problems. #11621 (comment)
• Fix couple of links to the web manual pages.
• Disable scarf seams on thick bridges. This is beneficial for print quality and it could also cause scraping the print bed if such bridge was on the second layer. #14190
• Added sequential arrange data for HT90.
• Fix crash during interlocking calculation in specific cases. #14163
• SLA: Fixed object placement on the bed after using auto-orientation. It stayed partially under the bed.

Translations

• Updated POT
• Updated CS, PL, DE, IT, ES, FR, JA dictionaries

Linux build is now distributed through Flathub. Please see the respective page on our Prusa Knowledge Base for instructions.

PrusaSlicer 2.9.1-alpha1

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Summary

This is the first alpha release of PrusaSlicer 2.9.1. This release introduces new algorithm to detect collisions during sequential printing, multi-material interlocking, and many bugfixes - mostly of older bugs.

To let you enjoy the alpha without worries, the alpha builds save their profiles into PrusaSlicer-alpha directory, so you may use the alpha side by side with the current release without ruining your production configuration.

Arrange for sequential printing

We are introducing a completely new algorithm to detect collisions during sequential printing. But not only that by far. We have actually made a new arrange algorithm that automatically positions and orders objects in such a way that collisions are avoided. Using sequential printing thus becomes safer and very easy to setup.

Just to give some context, PrusaSlicer allows sequential printing of objects (Print Settings -> Output options -> Complete individual objects) for very long time. This approach has both pros (less travels and stringing, smaller cost of a print fail) and cons (possibly longer print time because of cooling-related slowdown). However, printing objects sequentially also means that the print head has to travel downward after an object is finished, which opens a possibility of a collision with another object printed previously.

Until now, it was up to the user to decide whether current positioning and ordering of objects will lead to such a collision or not. While PrusaSlicer had a very crude check for collisions and while it showed outline of the extruder clearance area in the scene, it was quite misleading and giving extreme amount of false positive detections, rendering it hardly usable.

These times are now gone:

In addition, 3D model of the extruder is rendered when browsing through the Preview using the horizontal slider (as seen above). This is to help the user asses the situation. When a collision is detected, an error message is shown informing the user about which object was crashed into. The error does not block export of the G-code.

As of now, the feature is only provided for Prusa printers (except MK2 and HT90, the latter of which will be added before 2.9.1 final), because it requires detailed information about the extruder geometry. Printers by other manufacturers may be added later, if we are provided with the necessary data by the community. The exact format of the data may still change at this point (in general they are reasonably simple sets of extruder slices in heights where they change significantly plus the model for visualization). Testing and collecting feedback on the function as a whole is a priority at this point.

When PrusaSlicer does not have this extra information, it falls back to a very simple generic model based on extruder_clearance_radius and extruder_clearance_height config options. These options are in slicer for years and were used for the crude sequential printing check, we decided to keep them for this single purpose. The values were moved from Print Settings to Printer Settings, as they describe the physical geometry of the printer. The "fallback" model used for the algorithm is seen on the picture below, printing MK4 parts on an Ender:

Note that the horizontal slider has two modes - it can either browse through the whole print, or just the top layer. For assessing sequential printability, the first mode is probably more useful. The switch was in Preferences, but we have now also duplicated in it the slider settings menu in the bottom right corner, so it is readily accessible:

The algorithm heavily relies on z3 solver. Thanks to Microsoft for developing the library and releasing its source code publicly.

Related to #1052, #1095, #1662, #6474, #7787, #8948, #10216, #10709, #11834, #12592, #12815 and possibly others.

Multi-material interlocking #11588

Printing with multiple materials is often challenging regarding proper connection between adjacent parts. Especially some materials do not bind well together, meaning that the boundaries form weak spots in the resulting print. The same problem (to a lesser degree) affects prints with multiple extruders of the same material. To alleviate these issues, PrusaSlicer now has an option of interlocking the neighboring parts together:

The option can be turned on in Print Settings -> Multiple Extruders -> Advanced, where one also finds a couple of related parameters.

The feature was originally developed in Ultimaker Cura and it was later ported into OrcaSlicer. The implementation in PrusaSlicer was ported from there, with only minor modifications. We would like to express our gratitude to everyone involved in the development of this feature.

Configuration options to simplify printing with different materials

While PrusaSlicer in fact supports many scenarios in multitool/multimaterial printing, it was never very user friendly to set everything up in the user interface. In 2.9.0-beta1, we introduces an additional config option to help setup printing with multiple nozzle diameters. In this release, we are adding a similar tool to help with bed temperatures. The bed temperature is defined in Filament Settings, and it is not intuitive to see what happens if two filaments with different bed temperature in the config are used.

There is a new option in Print Settings -> Multiple Extruders -> Extruders -> Bed temperature by extruder, which specifies the extruder to take bed temperature from. Setting it to zero (which is the default) uses the simple logic that the first layer temperature is always taken from the first printing extruder, and the same applies to the second layer (which has a separate temperature settings).

A slicing warning informing the user about using differing bed temperatures now contains a hint to use this new parameter.

Other improvements with respect to 2.9.0

• Added a new configuration parameter for speed for printing solid infill above bridges (Print Settings -> Speed -> Over bridges) so it is possible to slow this difficult-to-print infill without slowing down the entire print.
• Add a new configuration parameter for speed of solid infill on the first layer (Print Settings -> Speed -> First layer solid infill speed).
• When sending multiple beds at once into Connect, the upload file dialog no longer allows to select a filename. Only the "bulk" naming dialog is shown after a printer is selected. This means that individual filename defaults retain correct print statistics (estimated times etc), instead of being overwritten by the filename for the first bed. #14078
• There are three buttons in SLA Material Settings - Material printing profile which set the values of all the tilt-related fields to predefined values corresponding to the legacy Fast, Slow and High viscosity profiles.

Bugs fixed with respect to 2.9.0

• Fixed incorrect visualization of travels in Preview when custom z-offset was used.
• Fixed uncommanded move to a random location in rare cases (caused by an uninitialized variable), possibly leading into digging the nozzle into the bed. #13826, #14079
• Fixed incorrect size of exported thumbnails when slicing using CLI (since 2.9.0, the thumbnail from the 3MF propagates to the G-code).
• Fixed rendering of bed numbers in Preview so they never render on the toolpaths. Also, the bed numbers newly show when viewed from under the bed. #13814
• Make wipe tower position and rotation accessible in placeholder parser again. #13684
• Fixed update of "state icons" in the Preview thumbnails when using Object Manipulation panel.

Bugs fixed with respect to 2.8.1

• When object and support layers end up too close to each other in a print with a wipe tower, the wipe tower layer was extremely thin and therefore very large. This is now fixed by merging such layer.
• Fixed invalidation problem resulting in missing infill when "wipe into this object's infill" was used. #13779
• Fixed incorrect fan speed until the first toolchange in multimaterial prints when "Prime all printing extruders" was enabled. First primed tool speed was used instead of the first printing extruder. #13721
• Measure tool was incorrectly disabled when any object was sunk under the bed.
• Fixed processing of meshes with cavities in SLA slicing. #13786
• Fixed gaps in the wipe tower in the first layer, appearing in specific cases.
• Fixed two independent cases when slicer incorrectly reported a cryptic error message referencing negative spacing. One was in Arachne perimeter generator (#13429), the other in multimaterial segmentation (#13836).
• Fixed undefined behaviour leading to crashes when extra assertion level was enabled during compilation (and possibly in other cases). #13859
• Fixed extrusion collision detection between a single object and wipe tower. #13444
• Fixed incorrect "slicing status" icon in the Preview when manipulating with different beds.
• "Wipe while retracting" was not working correctly in cases the extrusion was a single line instead of a loop. A "wipe" in a random direction was...

PrusaSlicer 2.9.0

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Summary

​This is final release of PrusaSlicer 2.9.0, introducing multiple beds, scarf seams, Printables integration, improved support for multiple nozzle diameters, paint-on fuzzy skin and many more improvements and bugfixes. The final release fixes three bugs found in 2.9.0-rc1. See the release logs of 2.9.0-rc1, 2.9.0-beta1 and 2.9.0-alpha1 for the complete list of changes with respect to 2.8.1.

Important note for Linux users: As noted before, we are now using Flathub as the only official distribution channel of PrusaSlicer on Linux. The reasons behind this decision and what it means for you are described at the end of 2.9.0-alpha1 release log.

Bugs fixed with respect to 2.9.0-rc1

• Fixed a crash in a specific case when slicing multimaterial-painted objects (#13676, #13798).
• Fixed a crash when slicing multimaterial-painted objects on a printer with less extruders than painted.
• Fixed highlighting of the active bed in case that the bed has a big custom model which would overlap neighboring beds (mentioned in #13791).

PrusaSlicer 2.9.0-rc1

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Summary

This is the first release candidate of PrusaSlicer 2.9.0. This release fixes couple of bugs found in 2.9.0-beta1.

The release candidate saves its profiles into regular PrusaSlicer configuration directory. When you first run it, it will search for all configurations produced by alpha or beta versions and offer to create a copy of the latest one.

Important note for Linux users: As noted during 2.8.x releases, we are now using Flathub as the only official distribution channel of PrusaSlicer on Linux. The reasons behind this decision and what it means for you are described at the end of 2.9.0-alpha1 release log.

Bugs fixed with respect to 2.9.0-beta1

• Windows specific: Export G-code button in the right panel was flickering on mouse move.
• The Slice Now button did not update after loading an object from the shape gallery (#13777).
• Fixed undefined behavior when sending G-code to print host. The issue only manifested on macOS with address sanitizer (#13766, #13759, #13750).
• A tenth bed was offered to the user after loading the project already containing maximum number of beds (a visual glitch, it was not possible to actually use the bed).
• Fixed empty thumbnail after adding a custom object into the shape gallery (bug introduced in 2.9.0-alpha1).
• Fixed freeze after a communication with Prusa Account returned a specific error code. This bug was uncovered by a problem on the server side couple of days ago which affected many PrusaSlicer users (#13768, #13762, #13765, #13762, #13745, #13757, #13758, #13748). Extra countermeasures were applied on both sides and they should prevent this from happening again.
• Fixed incomplete update when switching from FDM mode to SLA: out-of-bed status of volumes and thumbnails in bed selector were not updated correctly.
• Fixed a crash during slicing introduced between 2.9.0-alpha1 and 2.9.0-beta1.
• Fixed a crash when switching application language while using the bulk slicing screen.
• macOS specific: Loading screen displayed when web content is being loaded did not show.

Localization

• Updated POT.
• Updated CS, PL, DE, IT, ES, FR, JA dictionaries.
• Updated RU dictionary (#13438, thanks to @AndylgTom and Dmitry Sorkin).

Note on localization on Linux

When installing PrusaSlicer using Flatpak, only English and the system language are installed by default. In case you want to switch PrusaSlicer to another language, it is necessary to configure Flatpak to use these languages first. For example

sudo flatpak config --set extra-languages "pl_PL;de_DE"

will configure Polish and German for Flatpak. It is necessary to reinstall the application after.
Running the command with additional --user parameter will only configure the languages for current user, in which case sudo is not required.