nozzlefox

3MFSTL per colour

Split a model by colour

Turn a multi-colour or painted 3MF into one STL per colour, lined up, for Cura and any slicer.

  • Nothing uploaded
  • No sign-up
  • Free, no limits

Drop a multi-colour 3MF (or an OBJ with its MTL)

or paste it, or pick it from your device

.3mf · .obj · .mtl

  1. Drop a multi-colour 3MF
  2. Check the colours and their depth
  3. Download one STL per colour

Good to know

How to split a 3MF into one STL per colour

  1. Drop a multi-colour 3MF: one painted in Bambu Studio, PrusaSlicer or OrcaSlicer, or one with an object or part per colour, as on MakerWorld and Printables. An OBJ with its MTL file works too.
  2. Check the colours. Untick any you don't want.
  3. Download the zip: one STL per colour, named by colour, all in the same place. Load them together in your slicer as one object and give each STL its own filament or extruder.

Painted models

Painting in a slicer only colours the surface; the file doesn't say what's underneath. So each painted colour becomes a skin, as deep as the colour depth, the way slicers print it, and the main colour fills the rest. 1 to 1.5 mm is enough to hide the colour behind it; go deeper for light filaments over dark ones.

When you need this

  • Cura and other slicers that ignore 3MF colours: Cura reads the shapes in a Bambu or Prusa 3MF but not the painting, so a multi-colour model arrives in one colour. One STL per colour fixes that. If Cura shows no model at all, see why Cura finds no models.
  • IDEX and tool-changer printers: give each colour its own toolhead.
  • Printing colours separately: print each colour on its own and glue or press them together.

To keep all the objects of a 3MF as they are (not merged by colour), use 3MF to STL. To check a painted file first, open it in the 3MF viewer, which shows the painting.

Questions

How do I export each colour of a 3MF as its own STL?

Drop the 3MF into the tool on this page and click Download. You get a zip with one STL per colour, named by colour and lined up, ready to load together in any slicer.

Does it work with models painted in Bambu Studio or PrusaSlicer?

Yes. It reads the painting the slicers save in the 3MF (Bambu Studio, OrcaSlicer and PrusaSlicer use the same format) and turns each painted colour into a solid skin.

How do I print a Bambu multi-colour 3MF in Cura?

Split it here into one STL per colour, load all the STLs in Cura at once, group them as one object, and set a different extruder for each.

Why are painted colours only a skin?

Painting colours the surface only. Slicers print painted areas a few layers deep and fill the inside with the main colour; the colour depth slider sets how deep.

Is it free and private?

Yes. It runs in your browser, nothing is uploaded, and there's no sign-up.