Issue with KiCad StepUp export board colors

I started using KiCad StepUp today with the intention of fitting together multiple PCBs to make an enclosure in Fusion 360. I had almost no trouble getting the board in FreeCAD with traces and silkscreen, and I exported it as a STEP for Fusion. However, when I import the board into Fusion, everything (copper, tracks, silkscreen, pads, etc) on the bottom of the board has a kind of yellowish color to it. This happens both in the appearance and physical material menus, and I can’t visibly change either of the two (although they appear to change in the face preferences menu). The top of the board is fine and the strange color doesn’t occur in FreeCAD before export. It happens with seemingly any board I put into Fusion. Even stranger, when I enter the rendering workspace in Fusion, the colors on the bottom display up as expected. As a final test, I opened up the same STEP file in FreeCAD and found that the bottom also displayed as expected. What could be causing this? Too many materials for Fusion to display? Some other weird error?

@maui, author of StepUp is a member here. Might be after hours for him.

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this is a known issue in Fusion STEP format parsing… (IIRC it has been found in this forum or in FreeCAD forum)… you could check it using i.e. CADAssistant of OCC to load thew file and check it or with other STEP viewers.


Thanks for the reply. I know the files are fine because they show correctly in the render view and in FreeCAD. Do you know if anyone has found a fix for it in fusion? It’s not too much of a problem for me right now as the physical geometry is unchanged, but I could see it becoming an issue in the future.

you may find a workaround here:

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