Free online IGS to 3MF converter

Source format: IGS

IGS (more commonly seen as IGES, with the .igs or .iges extension) is a widely used CAD exchange format for sharing 2D and 3D engineering data between different design systems. It is used by mechanical engineers, product designers, manufacturers, and CAM/CNC workflows to move geometry between CAD platforms. Typical content includes surfaces, wireframes, curves, and sometimes solid geometry, but it does not preserve all native CAD features such as parametric history, constraints, or feature trees.

Target format: 3MF

3MF (3D Manufacturing Format) is a modern 3D printing and manufacturing file format designed to store printable models more reliably than older mesh formats. It supports units, materials, colors, build information, and multiple objects in one package. Compared with STL, 3MF is generally better for additive manufacturing because it is more compact, less ambiguous about scale, and can carry richer production data.

How to perform the conversion

Converting IGS to 3MF usually requires two stages: first, import the CAD geometry from the IGS file into a CAD or mesh-processing application; second, export or save as 3MF. Because IGS is a CAD exchange format and 3MF is a manufacturing mesh/package format, the conversion often involves tessellation (turning surfaces into a triangle mesh).

Best tool options:

• FreeCAD — good for opening IGS files and exporting meshes for 3D printing workflows.
• Fusion 360 or other CAD software that supports both import and 3MF export.
• SolidWorks, Siemens NX, CATIA, or similar professional CAD tools if available.

Typical workflow in FreeCAD:

1. Open FreeCAD and choose File → Open, then select the .igs file.
2. Inspect the imported geometry in the Part or Part Design workbench.
3. If needed, convert the imported surfaces into a solid or verify that the model is watertight.
4. Switch to the Mesh Design workbench and create a mesh from the shape using the appropriate mesh-from-shape command.
5. Export the resulting mesh as 3MF using File → Export and choose .3mf as the output format.

Typical workflow in Fusion 360 or similar CAD software:

1. Import the .igs file through File → Open or Insert → Insert CAD file, depending on the program.
2. Check that the model imports correctly and that units are interpreted properly.
3. Use the export or 3D print function to save the model as 3MF.

If your software cannot export 3MF directly: export the model as a mesh format first, then open that mesh in software that can save 3MF. For example, some workflows use .stl or .obj as an intermediate step, but direct 3MF export is preferable when available because it preserves more manufacturing information.

Notes on quality, compatibility, and limitations

IGS to 3MF is not a simple one-to-one format change. IGS stores CAD geometry, while 3MF stores a printable representation. That means the conversion usually loses parametric and feature-based CAD data. The result is typically a mesh suitable for printing, not an editable CAD model.

Units are important. IGS files may not always carry clear unit information, and 3MF expects consistent manufacturing units. Always verify scale after import and before export to avoid models that are too large or too small.

Surface quality depends on tessellation settings. A coarse mesh can produce faceted curves and poor print quality, while an overly fine mesh can create very large files. Choose a balanced mesh resolution for the intended printer and part size.

Not every IGS file converts cleanly. Files with gaps, self-intersections, or non-manifold geometry may need repair before export. If the model is not watertight, 3MF export may still succeed, but the result may not be suitable for 3D printing without fixing the geometry first.

3MF compatibility is good in modern slicers and CAD tools, but some older software may not fully support all 3MF features such as colors, materials, or multiple build items. If compatibility is a concern, test the exported file in your slicer before production.