Not only vertical colour mixing but also horizontal colour mixing possible with Repetier’s mixing firmware.
I designed the article in Openscad, exported the different colour components in .amf format, then used Slic3r 1.1.7 --> file --> Combine multi-material STL files… to re-assemble the colour .amf files exported from Openscad to build a complete .amf file. I then used Slic3r 1.2.1 to slice the files to a g-code file that was used for the print.
(I tried Slic3r 1.1.7 for the slice but gave up because the layers were all messed up)
I printed the infill before the perimeters to purge the previous colour in the infill.
http://deltaprinter.co.za/tri-colour/index.html
