Shannon McGarry
Discover how Autodesk Fusion helps you customize CNC post processors—from quick edits to advanced configurations—and test safely before production.
Overview: Post processors in Fusion
Post processors convert CAM toolpath data into machine‑specific code (G‑code), ensuring your program runs correctly on a given CNC machine.
Autodesk Fusion provides an online library with hundreds of free post processors that you can install and customize as needed. You can browse and install posts from the Fusion Online Post Library, store them in your cloud or local library, and edit them using the Fusion Post Extension for Visual Studio Code.
For simple adjustments, Post Properties can be edited directly from the NC Program or Post dialog, while more advanced changes require modifying the post configuration file itself.
If additional customization is needed, paid services are available through the Post Services Marketplace, and new post requests can be submitted via the Post Processor IdeaStation. Any changes should always be verified using a simulator or a dry run before running the program on a live machine.
How do I find and intall a post processor in Fusion?
- Where to look: Open the Online Post Library, it contains the most up-to-date posts, including some machine-specific posts with tailored properties and functionality.
- Install options:
- Install to your personal cloud library to access posts across devices.
- Install locally if you prefer local files.
- Quick steps:
- Search the online post library for your machine/controller
- Click install and choose cloud or local
- Open Fusion and confirm the post appears in your post library
How do I edit a post processor in Fusion?
- Edit using the Fusion Post Extension for Visual Studio Code:
- The extension helps locate and identify parts of the configuration file and the generated NC code.
- Edit the configuration file (the post code) there for precise changes.
- If you prefer not to edit configuration files, use Post Properties for many common tweaks (see below).
- If you don’t want to edit yourself, use the Post Services Marketplace for paid customizations from partners.
- Missing a post? Request creation on the Post Processor IdeaStation.
Quick comparison: Post processor edit methods in Fusion
| Edit method | Best for | Skill level | Risk level |
|---|---|---|---|
| Post Properties | Small, non‑code adjustments to output behavior | Beginner | Low |
| Edit configuration file (Visual Studio Code + Post Extension) | Complex or machine‑specific behavior changes | Intermediate–Advanced (some scripting helpful) | Medium – validate changes before running |
| Post Services Marketplace (paid) | Turnkey, professionally validated custom post processors | N/A | Low (when using vetted partners) |
Can I enable 4th and 5th axes in a post?
- Many posts in the Online Post Library already support 4th- and 5th-axis code, but those axes are often disabled by default.
- Options to enable:
- Often you can enable additional axes via Post Properties (simple toggle when available).
- Some posts require edits to the configuration file itself to expose or map the additional axes.
- Guidance: See the written guide to enabling 4th and 5th axes for details on axis properties and examples. As always, proceed with caution and test thoroughly.
What are post properties and when should I use them?
- Post properties let you make many common “edits” without opening the post file.
- Where to find them: NC program or post dialog inside Fusion.
- Typical uses:
- Change header/footer text in the output file
- Enable or disable certain flags or axes (when supported)
- Adjust feedrate or spindle formatting options exposed as properties
- Benefits:
- No need to edit code
- Reversible and low risk
- Faster for quick configuration changes
Security, safety, and best practices
- Always validate edited posts in simulation or a safe dry run before executing on a machine.
- Keep backups of original posts and version your edits.
- Limit access to modified posts if they could affect production workflows.
- If in doubt, use the Post Services Marketplace to obtain professionally validated post customizations.
Ready to start editing your own posts? Download a free 30-day trial of Fusion and visit the Online Post Library to find posts and get started.
Autodesk Fusion post processor frequently asked questions (FAQs)
A post processor converts Fusion CAM toolpath data into machine‑specific G‑code so your CNC machine can execute the program correctly.
Post processors are available through the Fusion Online Post Library, which contains the most up‑to‑date posts, including some machine‑specific options.
Yes. The Online Post Library includes some machine‑specific posts that expose more relevant properties, behaviors, and functionality for particular machines and controllers.
Not necessarily. Post Properties cover many common changes—such as toggling options or modifying output behavior—without writing code. For full configuration file edits, basic scripting familiarity helps, and the Fusion Post Extension for Visual Studio Code makes navigation and editing easier.
Post properties allow you to customize output behavior directly from the NC Program or Post dialog without editing the post file. They’re best for quick, low‑risk changes such as enabling supported axes, adjusting formatting, or toggling features.
For advanced edits, you can open the post configuration file using Visual Studio Code with the Fusion Post Extension, which helps identify editable sections and preview generated NC code.
Many posts already support 4‑ and 5‑axis output, but those axes are often disabled by default. In some cases, they can be enabled through Post Properties; in others, configuration file edits are required.
Issues can occur if the wrong post processor is used, required properties aren’t set correctly, or edits were made incorrectly to the post file. Verifying output and confirming machine compatibility is critical.
Use a CNC simulator or perform a dry run with the machine in a safe state. Validate the G‑code line‑by‑line if necessary, and always back up the original post before making changes.
Yes. Posts installed to your personal cloud library are accessible across devices, while locally installed posts remain available only on the machine where they’re stored.
You can request new or improved posts through the Post Processor IdeaStation or use the Post Services Marketplace to work with a partner on a paid, custom post.
You can request community or Autodesk attention through the Post Processor IdeaStation, or hire a vetted partner through the Post Services Marketplace for paid customization and validation.
Yes. The Post Services Marketplace offers professionally built and validated custom post processors for specific machines and workflows.
Keep backups of original posts, version your changes, limit access to modified posts in production environments, and always validate output before running on a live machine.