What the Free 3MF Splitter does
A 3MF file is a package, not a single mesh. Inside the ZIP-style container there's model XML, build items, object resources, material definitions, textures, thumbnails, relationships, and a pile of slicer-specific metadata. That structure is what makes 3MF more capable than STL - and it's also why "just pull one part out of this file" feels harder than it should.
This splitter opens the package in your browser, finds the main model file, and creates separate downloadable 3MF files from the build items, object resources, or the material and color triangle references it can read straight from the model XML.
Everything happens locally. The file is never uploaded to PrintNexus - which matters when the model is a client's file, an unreleased design, or just a 200 MB monster you don't want to push through an upload form.
How to split a 3MF by color, object, or build item
Build-item splitting is the cleanest mode. If your slicer or CAD tool exported separate printable items in the build section, the package already knows which object belongs on the plate - splitting along those lines almost always imports cleanly.
Object splitting gives you one downloadable 3MF per object resource. Use it to break apart simple assemblies or to figure out which object resource actually holds the part you care about.
Material/color splitting is for painted files. When mesh triangles carry 3MF property references - the way Bambu Studio and OrcaSlicer store painted color regions - the splitter groups matching triangles and exports the regions you select. You can pick several color regions before splitting, and the tool will create one part file per selected region plus a remaining body when geometry is left over. This mode is the most experimental, because slicers don't all store painted regions the same way.
Cutting a model in half
Manual cut is for models that are too tall, too wide, or awkward for your print bed. Choose Manual cut from Split source, pick the X, Y, or Z cut axis, then choose whether the solid side A or ghosted side B should stay active after the cut. Move the Position slider until the preview plane sits where you want the split, and use Tilt A and Tilt B when the seam needs to lean through the model instead of staying square.
Each cut saves the side you removed as a cut piece and keeps the chosen side as the current remaining body. You can move the plane again and cut that remaining body without the viewer snapping back to the original full model. Connector method can be None, Cylinder, or Square. If you use a connector, the connector side toggle chooses which half gets the plug. Always open every output in your slicer before printing, especially near painted areas because triangles crossing the cut may need repainting at the seam.
Why you should still inspect splits in your slicer
3MF is flexible, and every slicer writes its own flavor of metadata. A file from Bambu Studio, OrcaSlicer, PrusaSlicer, or Fusion can carry extra relationships, components, textures, build transforms, and vendor tags that don't survive a split intact.
That's why the splitter reports what it found before exporting anything. Build-item and object splits are usually straightforward; color splits depend entirely on how the original file stored its regions. Open every output in your slicer before committing a print to it.
Good uses
- Separating a multi-object 3MF into smaller, manageable files.
- Checking whether a painted Bambu Studio model actually exposes its color groups in the 3MF.
- Pulling one build item out of a large project package.
- Making quick inspection copies without uploading the model anywhere.
- Seeing what a slicer really put inside a 3MF package.
Limits
This is a package-level splitter, not CAD repair software. It doesn't remesh parts, heal geometry, generate connectors automatically in every mode, rebuild slicer-specific settings, or guarantee that every painted model splits into printable pieces. If an output imports strangely, try a different split mode or finish the cleanup in your slicer or CAD tool.