How to Export STL from CAD

Export the intended source revision and body selection, record the coordinate unit and tessellation settings, then reopen the saved derivative. Keep the native design as the authority for a named hole, contact face or other required feature.

Select the source revision and intended parts

Save the native revision and list the expected output files. Decide which bodies/components belong, including hidden or suppressed items. A surface-only body needs an explicit decision; a complete-looking viewer image does not identify missing inventory.

Choose coordinate unit and mesh settings

STL has no unit declaration. Record what one coordinate unit represents. Choose binary for compact triangle records when the recipient accepts it, or text for a specific receiving requirement. Record exact exporter labels, values and units rather than only a preset name. Chord and angular settings control source approximation; they do not certify printed fit.

Follow the documented application workflow

The two workflows below were checked against official help on 26 October 2026. No installed Fusion build or authenticated Onshape export was executed. Confirm the labels in the version you actually use.

Autodesk Fusion: documented desktop workflow

In the Design workspace, right-click the intended body or component in the Browser and choose Save As Mesh. Choose STL Binary, set Unit Type, and choose One File or One Body Per File as appropriate; save the export. This selection determines which bodies reach the file. Review refinement settings offered by your installed version rather than assuming a preset preserves a small hole.

Source: Autodesk Save As Mesh documentation. Reviewed 26 October 2026 for the current Fusion help workflow. An installed Fusion build was not available for verification; this is a documented workflow, not a claimed execution in a specific build.

Onshape: documented browser workflow

Select the intended part or parts in a Part Studio and use Export from the context menu. Choose STL, Binary or Text, export units and a resolution. Custom STL resolution exposes chordal tolerance, angular deviation and minimum facet width. For separate outputs, review the option to export individual parts, then download and inspect the files.

Source: Onshape Exporting Files help, reviewed 26 October 2026. This describes the current browser help; no authenticated Onshape session or application screenshot was used.

Reopen and check the derivative

1. Preserve the source and identify the exact saved STL, not an earlier working copy.
2. Open it in the local viewer with the known unit. Confirm every intended piece and one outer reference dimension.
3. An outer span catches a scale mistake but can miss a changed opening. Record a feature the recipient actually needs, such as the width of a square hole, and verify it separately. Use the source design dimension as the requirement; the mesh viewer shows the exported approximation.
4. Use revision comparison for before/after evidence and shell interpretation for unexpected pieces. Check relevant slicer layers before accepting the next stage.

Generated-geometry example: the original square-hole block spans 40 × 30 × 10 mm with an 8 mm opening. The deliberate revision keeps those outer spans and 32 triangles but reduces the opening to 6 mm. These are owned mathematical controls, not executed CAD exports. Equal outside dimensions cannot approve that change.

Download the blank export record (CSV)

Send a concise export note

Tell the recipient what one STL coordinate unit represents, which revision was exported and which reference dimension they should check after opening the file. Example for the generated control: “r01; millimetre coordinates; outer X = 40 mm; square opening = 8 mm. Check both after opening. No CAD-application or physical-print test is claimed.”

Stop and return to source when an intended body is absent, a required feature disagrees or a solid has an unexplained opening. Repeated conversion cannot recover a native feature timeline.