Two user reports from the same session on the deployed build, 2026-08-23.
FIRST: "if I select a shape (es a circle draw in construction lines) and then I
try to toggle contruction to obtain a full line, does not work". Reproduced: Q
converts the selection and so does the offer's Reference > Construction row —
both run m_keys_sketch['Q'] — but the CHECKBOX, the one control actually
labelled Construction, only ever called set_sketch_construction(), which arms
the mode for the NEXT entity. So the obvious control was the one route that
could not convert existing geometry, and it failed silently while also flipping
the draw mode behind the user's back. It now carries Q's meaning.
Scoped to Select mode, and that scoping is not cosmetic: drawing AUTO-SELECTS
what was just drawn (draw-then-edit), so with a draw tool armed "there is a
selection" does not mean the user picked anything — it means they finished a
line. The first version converted there and turned the box into a trap: arm
construction, draw the axis, click the box to go back to real geometry, and
instead of disarming the mode it converted the axis just drawn. The gesture
ladder's C4 rung does exactly that and reported three construction entities
where it wanted one. In Select mode the intent is unambiguous.
SECOND, and this one destroyed work: "after creation of a circle, a round angled
rectangle and a slot, and mirror of those shapes on a vertical line inside a
outer rectangle, preview is ok but application creates errors: the circle is
mirrored, but rectangle and slot are redrawn as pieces of circles screwing both
the original shapes and the copies." A screenshot came with it, and it showed
more than the words did: the ORIGINALS were wrecked too — the rounded rectangle
was drawn as a four-lobed cloud, each corner fillet having gone the long way
round, and the slot had ballooned into two near-full circles.
Measured on the rig, a slot mirrored about a vertical line:
rails 62.873 / 62.873 -> 2.082 / 62.913
caps r=21.554 sweep=-180.00 -> r=32.214 sweep=-237.66
and all four sources moved, the axis line with them
Cause: confirm_op's Mirror branch bound an Arc copy to its source with a
Symmetric constraint on the CENTRE ALONE. An arc has five degrees of freedom;
pinning two of them leaves the endpoints and the sweep free while the shape's
own coincidences still pull on them, and the solver answers with a different,
internally consistent sketch — which is what a reflex cap and a 2 mm rail are.
A circle came through the same code untouched because a circle HAS no endpoints
to leave free, which is exactly why the failure reads as "circles fine, rounded
rectangles and slots destroyed".
Three parts, and each one is here because the measurement caught the previous
one being half a fix:
1. Arcs are bound by BOTH ENDPOINTS. Endpoints before centre in the ladder:
{p0, p1} is four equations against five DoF and pins the sweep, while
{centre, p0, p1} is six and is refused — the refusal is what silently
degraded the batch to a set that left the sweep free.
2. Every copy is reflected from the PRE-BATCH source, so a batch that disturbs
the sketch cannot hand the next copy already-moved geometry.
3. THE APPLIED RESULT IS THE PREVIEW — checked on the sources AND the copies,
and on violation the whole constraint web is dropped and both halves are
restored to the reflection the preview drew. try_add_constraints rolls back
only when a solve FAILS, and every failure here came from a solve that
succeeded at something else. Guarding only the sources fixed the slot and
left the rounded rectangle's copies at a 13.8 mm rail and a 308 degree cap:
the original was safe and the copy was still wrong, which is half a fix.
The parametric link is kept whenever it provably holds the geometry, and dropped
when it does not. A wrong shape is worse than an unlinked one.
WHY NOTHING CAUGHT THIS: the gesture ladder's mirror rung reflects three
straight LINES. It sat green through the whole defect. C4b now mirrors a slot,
so the reflection has arcs in it, and grades the property the user actually
stated: the copy is the source reflected, the source does not move, and no cap
comes back reflex.
VERIFIED against the user's own scene, rebuilt gesture by gesture on the rig —
outer rectangle, circle, rounded rectangle and slot, a vertical CONSTRUCTION
line as the axis, all 17 entities mirrored in one gesture:
ok the mirror axis is a construction line
ok picked the axis and all 17 entities
ok originals unchanged (moved: [])
ok every copy is the exact reflection (worst 0.000000000)
ok no source arc turned reflex — the 'cloud' failure
ok no copied arc turned reflex (6 arcs checked)
One grader correction worth recording, because it cost a round and would cost
the next one too: a reflection REVERSES ORIENTATION, so a copy legitimately
stores p0/p1 the other way round. Comparing p0 to p0 grades the storage order,
not the geometry, and reported a perfect mirror as an 8.98 mm error. Endpoints
are compared as an unordered pair.
OrcaSlicer: an open source Next-Gen Slicing Software for Precision 3D Prints.
Optimize your prints with ultra-fast slicing, intelligent support generation, and seamless printer compatibility—engineered for perfection.
Official links and community
Official Website:
Github Repository:
Follow us:
Join our Discord community:
|
⚠️ CAUTION: Several clickbait and malicious websites, such as orca-slicer[.]com and orcaslicer[.]net, are pretending to be the official OrcaSlicer site. These sites may redirect you to dangerous downloads or contain misleading information. Our only official website is www.orcaslicer.com. If you come across any of these in search results, please report them as unsafe or phishing to help keep the community secure with: - Google Safe Browsing - Microsoft Security Intelligence - IPThreat |
Main features
- Advanced Calibration Tools
Comprehensive suite: temperature towers, flow rate, retraction & more for optimal performance. - Precise Wall and Seam Control
Adjust outer wall spacing and apply scarf seams to enhance print accuracy. - Sandwich Mode and Polyholes Support
Use varied infill patterns and accurate hole shapes for improved clarity. - Overhang and Support Optimization
Modify geometry for printable overhangs with precise support placement. - Granular Controls and Customization
Fine-tune print speed, layer height, pressure, and temperature with precision. - Network Printer Support
Seamless integration with Klipper, PrusaLink, and OctoPrint for remote control. - Mouse Ear Brims & Adaptive Bed Mesh
Automatic brims and adaptive mesh calibration ensure consistent adhesion. - User-Friendly Interface
Intuitive drag-and-drop design with pre-made profiles for popular printers. - Open-Source & Community Driven
Regular updates fueled by continuous community contributions. - Wide Printer Compatibility
Supports a broad range of printers: Bambu Lab, Prusa, Creality, Voron, and more. - Additional features can be found in the change notes.
Wiki
The wiki aims to provide a detailed explanation of the slicer settings, including how to maximize their use and how to calibrate and set up your printer.
Download
Stable Release
📥 Download the Latest Stable Release
Visit our GitHub Releases page for the latest stable version of OrcaSlicer, recommended for most users.
Nightly Builds
🌙 Download the Latest Nightly Build
Explore the latest developments in OrcaSlicer with our nightly builds. Feedback on these versions is highly appreciated.
Belt Printer Builds
The nightly release ships two parallel builds: the standard build and a belt-printer build. Both are attached to the same release — tell them apart by the filename suffix:
- Standard — no suffix (e.g.
OrcaSlicer_Windows_Installer_x64_nightly.exe) - Belt —
_beltsuffix (e.g.OrcaSlicer_Windows_Installer_x64_nightly_belt.exe)
The _belt builds add experimental support for belt / conveyor (infinite-Z) printers, where the model is sliced against a tilted belt surface instead of a flat horizontal bed. They include ready-to-use belt printer profiles, the full belt slicing pipeline (mesh rotation and G-code transforms), belt-aware support generation, and a tilted-bed preview.
⚠️ Belt printer support is under active development and is not yet merged into
main— it currently ships only in these parallel_beltbuilds, produced from thebelt-printerbranch. See tracking PR #14394 and the original documentation in #12998.
How to install
Windows
Download the Windows Installer exe for your preferred version from the releases page. Both x64 and arm64 installers are published — pick the one matching your CPU.
-
For convenience there is also a portable build available.
Troubleshooting
- If you have troubles to run the build, you might need to install following runtimes:
- MicrosoftEdgeWebView2RuntimeInstallerX64
- vcredist2019_x64
- Alternative Download Link Hosted by Microsoft
- This file may already be available on your computer if you've installed visual studio. Check the following location:
%VCINSTALLDIR%Redist\MSVC\v142
Microsoft Store
Install from the Microsoft Store when you prefer a Store-signed package (helps on Windows 11 Smart App Control).
Windows Package Manager
winget install --id=SoftFever.OrcaSlicer -e
Mac
-
Download the universal DMG, which runs on both Apple Silicon and Intel Macs.
-
Drag OrcaSlicer.app to Application folder.
-
If you want to run a build from a PR, you also need to follow the instructions below:
Quarantine
-
Option 1 (You only need to do this once. After that the app can be opened normally.):
- Step 1: Hold cmd and right click the app, from the context menu choose Open.
- Step 2: A warning window will pop up, click Open
-
Option 2: Execute this command in terminal:
xattr -dr com.apple.quarantine /Applications/OrcaSlicer.app -
Option 3:
-
Homebrew Cask
brew install --cask orcaslicer
The Homebrew cask installs the official macOS DMG from GitHub Releases.
Linux
Flathub (Recommended)
OrcaSlicer is available through FlatHub:
Install from the command line:
flatpak install flathub com.orcaslicer.OrcaSlicer
flatpak run com.orcaslicer.OrcaSlicer
It can also be installed through graphical software managers (KDE Discover, GNOME Software, etc.) when Flathub is enabled. Search for OrcaSlicer in your software center.
AppImage
AppImages are published for both x86_64 and aarch64 (ARM64). Pick the file matching your CPU — the ARM64 build has aarch64 in its name (e.g. OrcaSlicer_Linux_AppImage_Ubuntu2404_aarch64_*.AppImage).
-
Download App image from the releases page.
-
Double click the downloaded file to run it.
-
If you run into trouble executing it, try this command in the terminal:
chmod +x /path_to_appimage/OrcaSlicer_Linux.AppImage
How to Compile
All updated build instructions for Windows, macOS, and Linux are now available on the official OrcaSlicer Wiki - How to build page.
Please refer to the wiki to ensure you're following the latest and most accurate steps for your platform.
Klipper Note
If you're running Klipper, it's recommended to add the following configuration to your printer.cfg file.
# Enable object exclusion
[exclude_object]
# Enable arcs support
[gcode_arcs]
resolution: 0.1
Supports
OrcaSlicer is an open-source project, and we're deeply grateful to all our sponsors and backers.
Their generous support helps fund filaments and other essential 3D printing materials for the project.
Thank you! :)
Sponsors
|
|
Backers:
Ko-fi supporters ☕: Backers list
Support the project
Some Background
Open-source slicing has always been built on a tradition of collaboration and attribution. Slic3r, created by Alessandro Ranellucci and the RepRap community, laid the foundation. PrusaSlicer by Prusa Research built on Slic3r and acknowledged that heritage. Bambu Studio in turn forked from PrusaSlicer, and SuperSlicer by @supermerill extended PrusaSlicer with community-driven enhancements. Each project carried the work of its predecessors forward, crediting those who came before.
OrcaSlicer began in that same spirit, drawing from BambuStudio, PrusaSlicer, and ideas inspired by CuraSlicer and SuperSlicer. But it has since grown far beyond its origins. Through relentless innovation — introducing advanced calibration tools, precise wall and seam control, tree supports, adaptive slicing, and hundreds of other features — OrcaSlicer has become the most widely used and actively developed open-source slicer in the 3D printing community. Many of its innovations have been adopted by other slicers, making it a driving force for the entire industry.
The OrcaSlicer logo was designed by community member Justin Levine.
License
- OrcaSlicer is licensed under the GNU Affero General Public License, version 3.
- The GNU Affero General Public License, version 3 ensures that if you use any part of this software in any way (even behind a web server), your software must be released under the same license.
- OrcaSlicer includes a pressure advance calibration pattern test adapted from Andrew Ellis' generator, which is licensed under GNU General Public License, version 3. Ellis' generator is itself adapted from a generator developed by Sineos for Marlin, which is licensed under GNU General Public License, version 3.
- The Bambu networking plugin is based on non-free libraries from BambuLab. It is optional to the OrcaSlicer and provides extended functionalities for Bambulab printer users.


