Troubleshooting & FAQ

The import dialog was probably left on Geometry Only mode, or the file doesn't have embedded color data.

Re-import and confirm Material Mode is set to Import Materials. After import, select an object and check the Slicer Info sub-panel in the 3MF N-panel tab — if it's empty, the file never had slicer color data embedded at all.

MMU paint data only converts to an editable UV texture when you import with Material Mode → Import MMU Paint Data. Standard import reads the data as materials but doesn't build the texture.

Re-import with that mode selected, then switch to Texture Paint mode to see and edit the zones.

You're importing with Import MMU Paint Data on a high-poly model. This mode subdivides every triangle and paints segmentation data onto a texture — it's inherently slow on dense meshes.

If you just need to view the file, use Import Materials instead. It's much faster and still brings in the colors. Use the paint import mode only when you actually need to edit the zones.

Check the Location setting in the import dialog. Keep Original places objects where the 3MF file stored them, which can be far from the world origin if the file came from a slicer with a build plate offset.

Re-import with Location → World Origin or 3D Cursor to bring everything to a known position.

If you exported with Material Export Mode → Standard 3MF but the original file had Orca-specific paint data, the colors get written as standard materials (colorgroups/basematerials) — not as per-triangle paint zones. The slicer receives colors but not the zone assignments.

To preserve the slicer paint zones, export with Material Export Mode → Paint Segmentation and select the right slicer format.

The most likely cause is that Auto mode didn't promote to Paint Segmentation because the objects have no paint textures. Check that your object actually has paint data: select it, press N, and look for the MMU Paint sub-panel in the 3MF tab.

If the sub-panel is empty, Initialize Painting was never run — there's nothing to export as paint segmentation. Either initialize and paint first, or use Object or Face Colors for material-based coloring instead.

This usually means objects that look the same color actually have different material datablocks — same RGB, different material names. PrusaSlicer maps by extruder slot, not color value.

In Blender, select all objects that should share a color, then open the Material Properties panel and re-assign them all to the same single material. Only one material entry should exist for each color. Re-export and PrusaSlicer will map them to the same extruder correctly.

Services that don't support 3MF component hierarchies reject files where objects are parented to an Empty. Enable Flatten Hierarchy in the export dialog — this writes all objects as top-level build items with no component nesting.

If the service supports full-color texture printing (like JLC3DP's full-color service), use Material Export Mode → Standard 3MF instead of Paint Segmentation. Standard export preserves the texture data in spec-compliant format that these services can read.

Segmentation encoding is the slowest part of the addon — it recursively subdivides every triangle and traverses the painted texture.

Try lowering Subdivision Depth in the export dialog (default 7). Dropping to depth 5 or 6 is roughly an 4–8x speedup with only a modest loss in color boundary sharpness, and is often enough for most models.

A few things contribute to large exports:

• High Subdivision Depth on a dense mesh — reduce depth or reduce polygon count first
• High-resolution paint texture — the texture is embedded in the archive. A 16K texture is around 256MB uncompressed
• No compression — check Archive → Compression in the export dialog (default 3 is a reasonable balance)
• Many unique objects with no shared geometry — enable Use Components if you have repeated meshes in the scene

Geometry node setups that use instancing (like the Text node, or any node that outputs instances rather than realized geometry) don't export correctly on their own. Add a Realize Instances node after the last node in your graph before the output, then export again.

You can confirm this is the issue by applying the modifier to a duplicate object first — if the applied result looks correct in the viewport, the Realize Instances node is the fix.

The MMU Paint panel only appears in Texture Paint mode. Switch the interaction mode (top-left of the 3D Viewport) to Texture Paint, then press N and look for the 3MF tab.

The mesh already has a paint texture — you're in active paint state, not setup state. If you want to start over, the paint texture can be deleted from the UV Editor or Image Editor header.

A non-constant brush falloff creates soft edges that the encoder can't cleanly assign to a single filament. The panel shows a warning when this is the case — click Fix Brush Falloff to snap the brush to Constant. Then run Quantize to Filaments before exporting to clean up any accumulated blur.

Use Reassign Filament Color in the filament list. Select the filament you want to replace, click Reassign, and pick the replacement. It bulk-replaces every pixel of that color across the entire texture in one operation — much faster than painting over it.

Lower the Region Similarity value (default 0.20) and run it again. A lower value requires regions to be more similar before merging adjacent patches, preserving finer distinctions.

If similar-looking filament colors keep getting merged, also check that the entries in your filament list are sufficiently distinct from each other.

No. You can export any Blender scene directly. For plain geometry, just go to File → Export → 3D Manufacturing Format (.3mf). For MMU painting, use the Initialize Painting workflow in the 3MF N-panel on any existing mesh. A reference import is only needed if you want to embed a slicer's printer config — and even that can be replaced with a saved Slicer Profile.

Not currently. Cura uses a blue-channel PNG encoding for color zones that is completely different from the Orca/Bambu or Prusa formats. It's on the research list but not implemented.

You need either a saved Slicer Profile embedded in the export (see Slicer Profiles), or the file you originally imported from had embedded config data to round-trip.

Check the Slicer Info sub-panel in the 3MF N-panel after import — if it lists config file names, those will carry through automatically. If it's empty, configure the slicer manually or load a profile first.

Import and export defaults live in Edit → Preferences → Add-ons → 3MF → Import and Export tabs. Slicer Profiles live in the Advanced tab. Filament list data and paint textures for a specific model are stored on the mesh/scene in the .blend file.

Minimum supported version is Blender 4.2. The addon is primarily developed on Blender 5.0. If something looks or behaves differently from what this guide describes, check that you're on 4.2 or newer.