Bambu Slicer won't show filament change

Hi all

I have loaded a design from FUSION 360 into Bambu Slicer. I colour each part as required. I have the design as a .STEP file so that it shows the different parts to colour. In the prepare area it shows each part coloured as it should be, but when I slice it, it changes it to a solid colour. There is no filament change showing either.

The word UNO is on the first layer (base layer) in the file and is laying on the bed. The thickness of the word is 1mm into the lid.

What am I missing? Why is changing to a solid colour when slicing? Please help.


Have you selected all of your parts and “assembled” them (select parts, right click, assemble)


Thanks for the idea. However, when I right click, I don’t have an option to Assemble. I have split them and then re-assembled them, but the same thing happens. The bottom layer is the main colour of the print - not the colour I need.

Looks like the letters are not cut out in the Top.
In this case the slicer does not know which color to use and uses the main color of the assembly.