I am having a similar issue. Can you confirm that we can't render colors at all with union? I have 10 cubes of different colors. After render with union, the display has no colors. Do the STL files save without colors for different vertices?? -- View this message in context: http://forum.openscad.org/Color-in-Compile-and-Render-mode-tp4637p13693.html Sent from the OpenSCAD mailing list archive at Nabble.com.