3MF to OBJ

preslice writes OBJ from the meshes it has already read, so the export happens in the tab and your .3mf is left alone.

How do I save one mesh as OBJ?

1. Drop the .3mf on preslice.co.
2. Open the 3MF Content tab and expand Mesh objects.
3. Click Export OBJ, under Export STL, on the mesh you want.

The button sits on each mesh, not on each object, so an object built from three parts lists three meshes. The file takes the mesh's name, and an unnamed mesh saves as mesh-<id>.obj, such as mesh-3.obj.

How do I save every mesh at once?

Export all as OBJ sits in the Mesh objects header. It writes one ZIP named after your file, so benchy-plate.3mf gives you benchy-plate-obj.zip with one OBJ per mesh inside.

What does the OBJ keep?

The mesh name, and the position the part was modelled at, not where the slicer put it. Numbers are in millimetres, but an OBJ has no place to write the unit, so the next program has to assume it.

What does it lose?

Paint and colour, units, plates, and every print setting. The .3mf still has them. See 3MF against STL for the same trade.

OBJ or STL?

Both hold triangles and nothing else here. Pick OBJ when the next program wants named parts, as Blender does. Pick STL when it is a slicer or a print service. See 3MF to STL.

Can I get OBJ from my slicer?

Toolpaths are the printed lines, not the model. For the model from Bambu Studio or OrcaSlicer, use the steps above.