How to Export a 3D Model to 3MF for Bambu Studio or PrusaSlicer on Mac

You found the model you want to print, but it came as an .fbx, a .glb or a .usdz. Your slicer wants STL or 3MF. On a Mac the usual route was a detour through Blender: import, fix the scale, stand the model upright, export, and hope the colours did not matter.

Since version 1.5.2, Eyemesh exports straight to 3MF, a format that Bambu Studio, PrusaSlicer, OrcaSlicer and Cura all read. Here is how it works, and what ends up in the file.

Why 3MF rather than STL

STL describes triangles and nothing else. 3MF is a more recent format built for printing: it declares its unit, it can hold colours, and it is compressed. If you are not sure which one to send, we compare them in detail in STL or 3MF: which format for your slicer. For a model that comes from a game, a scan or a web viewer, 3MF keeps more of what made it look right.

Export a model to 3MF in four steps

1. Install Eyemesh from the Mac App Store and open your model: drag it into the window or use File > Open (Cmd+O). Eyemesh reads 17 formats, including FBX, GLB, glTF, OBJ, USDZ, DAE, 3DS, PLY and Unity packages.
2. Check it in the 3D view. The inspector shows its dimensions and triangle count, and the cross-section view tells you whether it is solid or hollow before you commit filament to it.
3. Click the export icon in the toolbar and choose 3MF.
4. Choose where to save. Eyemesh writes a single self-contained .3mf, ready to drop into your slicer.

What Eyemesh puts in the 3MF

• One object, not a pile of parts. A game asset or a scene is often made of dozens of separate meshes. Eyemesh merges them into a single object with every part in its place, so the slicer does not spread them across the plate.
• The right way up. Most 3D tools work with Y pointing up, printers with Z. Eyemesh turns the model so it stands on the plate the way it stands in the viewer.
• Millimetres, without rescaling. The file declares millimetres and the coordinates are written as they are, exactly like the STL export. A model authored at 40 units arrives at 40 mm.
• Its colours. Each colour of the model becomes a material in the 3MF. For a textured model, Eyemesh reads the texture under each triangle, so a low-poly asset painted with a small colour palette keeps its colours instead of turning grey.
• A clean mesh. Degenerate triangles, which 3MF does not accept, are left out.

Give an STL a colour before exporting

An STL, or any model without materials, shows up in neutral grey. Eyemesh lets you pick a colour for the model in the viewer's background menu, under Model color, or set a default for every material-less model in Settings. That colour is kept on export: an STL you tinted orange arrives in the 3MF in orange.

Convert a whole folder at once

Select several models in the browser, choose 3MF as the target, and Eyemesh queues them and processes them one after another. A pack of 30 FBX miniatures becomes 30 3MF files in one pass, and your originals are never modified. More on the export queue on the format conversion page.

What stays in the slicer

A 3MF written by Eyemesh carries the geometry, the unit and the colours. It carries no print settings: printer profile, layer height, supports, infill, filament assignment. That is your slicer's job, and the reason Bambu Studio and PrusaSlicer save their own project 3MF files. Open the exported file there, set up the print as usual, and save the project from the slicer.

FAQ

Which slicers open the 3MF files from Eyemesh?

Eyemesh writes standard 3MF, following the core specification of the 3MF Consortium. Bambu Studio, PrusaSlicer, OrcaSlicer and Cura all import that format.

Will my slicer print the colours automatically?

The colours are in the file, but what happens next depends on your slicer and your printer. On a single-filament printer the model prints in the filament you load. Matching colours to filaments remains a step you take in the slicer.

Why does my GLB model arrive tiny in the slicer?

glTF and GLB are defined in metres, while slicers read millimetres. Eyemesh does not guess a scale, it writes the coordinates as they are: a 1.8-unit figure arrives 1.8 mm tall. Scale it up in the slicer to the size you want, as you would with an STL exported from the same file.

Can I export a 3MF from a file that is already a 3MF?

Yes. Opening a 3MF and exporting it again merges its objects into one, which is handy when a downloaded file spreads its parts across the plate.

Is my file uploaded anywhere?

No. The conversion runs entirely on your Mac, nothing leaves it.