Fusion 360 is one of the most popular CAD tools for 3D printing — it's free for personal and small business use and produces excellent geometry. Getting the STL export settings right makes a meaningful difference to print quality. This guide covers the current Fusion 360 export process.
Method 1: Export from the Design workspace (quickest)
- With your design open, right-click on the body or component you want to export in the browser panel (left side of screen)
- Select Save As Mesh
- In the dialog that opens, set:
- Format: STL (Binary)
- Structure: One File Per Body (or One File, depending on your design)
- Refinement: High (recommended for printing)
- Units: mm (millimetres — important)
- Click OK and choose where to save the file
Method 2: Export via File menu
- Go to File → Export
- Set the file type to STL Files (*.stl)
- Click Options to access the refinement settings — set Refinement to High
- Ensure units are set to millimetres
- Click Export
Understanding the Refinement setting
The Refinement setting controls how many triangles are used to approximate curved surfaces in the STL file. More triangles means larger file size but smoother curves in the print.
- Low: Visible faceting on curves. Only use if file size is critical.
- Medium: Adequate for most prints. Some faceting on tight curves.
- High: Our recommendation. Smooth curves, reasonable file size.
- Custom: Lets you set specific deviation and angle tolerances. A surface deviation of 0.005–0.01 mm is excellent for printing.
Check units: the most common mistake
Fusion 360 designs can be in millimetres or inches. STL files don't store unit information — just coordinates. If you designed in millimetres and export to inches (or vice versa), the resulting print will be the wrong size by a factor of 25.4.
Always confirm that your export units match your design units. The easiest check: after exporting, open the STL in a slicer and verify the overall dimensions are what you expect.
Assemblies and multiple bodies
If your design has multiple bodies or components:
- For parts that will be printed separately: Export each body as a separate STL file. Right-click each body individually and save as mesh.
- For parts that should print as one piece: Combine the bodies before export (Modify → Combine) or select "One File" in the export dialog.
After exporting
Open the exported STL in a slicer (Bambu Studio or Cura) to verify:
- The dimensions are correct
- The geometry looks as expected — no missing faces or unexpected holes
- The part is on the build plate, not floating in space
Once you're satisfied, use our instant quote tool to upload the file and get a price. See also: How to prepare an STL file for printing.
Common questions
Where is the STL export option in Fusion 360?
Right-click the body or component in the browser tree and choose Save as Mesh. Exporting from the root exports everything, which is rarely what you want.
What refinement setting should I use?
High is a safe default for most parts. Custom with a surface deviation around 0.01 mm gives smooth curves without the file becoming needlessly large.
Should I export each body separately?
Yes, if the parts are separate items. One STL per body keeps them independent so we can orient and price each properly rather than printing them fused.
Why does my exported part come out the wrong size?
Check the export units. Fusion will happily write centimetres or inches, and because STL carries no units the slicer assumes millimetres and scales the part wrongly.
Can I send a Fusion file instead of an STL?
Send a STEP export rather than the native file. STEP keeps true geometry and units, so we can adjust clearances properly without editing a mesh.
Does the design history or timeline matter to you?
No. We only need the finished geometry. Nothing about how you built the model affects how it prints or what it costs.
Published 9 September 2026 · last reviewed 5 October 2026.
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