What's the best design software for multi-colour objects?

I’ve just added an AMS to my P1P, it’s all working well and I’ve colourised a few old models in Bambu Studio as tests.

What’s the best way to create new models in multi-colour and export them to STL for printing? My favourite tool is OpenSCAD, which does support colour, but then strips out all the colour information when exporting as STL, which is frustrating.

What software do you all use?


Personally I use Solidworks, Fusion and Onshape but on all of them there are several different ways to approach designing for multicolor printing.
Did you try to export as 3mf or amf format from OpenSCAD or save as multipart STL for the different colors? The colors as designed may not appear in the slicer when imported but usually it is easy to put colors onto the separate objects within the slicer after the import.

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Yes, I tried both AMF and 3MF, but OpenSCAD removes all colour information as soon as the model is rendered, before exporting can happen, so nothing works - I guess it’s rendering to a strict reading of the STL format, or something.

I’ve found the personal version of Fusion 360, so I’ll have a play with the UI and see what I can get out of it. It’d be nice to find a properly portable file format for this stuff, though.


When I model, I split every different colour into a separate object and then export them as one stl. When I open that stl in Bambu Studio, I right click on it and split into parts. I then colour each part as needed.


question, when you imported the STL file into Bambu Studio did you try to split the object to obtain the separate color objects?

That option is greyed out, so I assume it’s one indivisible object in the STL file once OpenSCAD has finished rendering.

What do you use to do the modelling? I’m pretty sure OpenSCAD can’t do that, although I will have a poke around and see what I can do.


When I model in fusion I try to have each item I want in a different color as a separate body. At the end I save all as mesh to a single 3mf file. Once opened in Bambu Studio it offers to import it as one assembly but with multiple parts. They can then easily be selected and colored in the objects list.

If you want to hand color / paint there is a big update in the new Bambu Studio by supporting .obj files and making use of the Vettex colors. This way you can also paint in apps like nomad Sculpt, Blender or similar. Just make sure to save there as obj and have vertex colors enabled. Apps like Nomad have it in their export menu.

All useful information, thanks. I had written Fusion off as too expensive, but I see they have a free Personal licence now, so I’ll take another look and see if I can get my head around the user interface.


I use a CAD program called Shapr3D. I do exactly what Leif3D is describing. In CAD, each colour is modelled as it’s own body and then exported as one .stl

When you open the .stl up in Bambu Studio, you split it into parts and colour each part as needed. I do it this way to avoid colour bleeding. The above picture is the leg from my Sliced Bread model.

If I were to model it as one piece and then use the colouring tool within Bambu Studio to colour the crust, it will look perfectly fine on the outside, but the colouring goes all over the place during the infill.

The leg on the left is modelled as a multi part stl, split and coloured. The leg on the right is a single part stl that has been coloured in Bambu Studio.

On the right, you can see that when it gets to the infill, the colours do their own thing and when you’re dealing with light and dark colours, the dark will show through the light on the finished piece.

Very useful, thanks, I’ll take a look at it.