Filament Colouring using Inkjet Ink

thingiverse

So I had only a few rolls of filament left and wanted more colors, so I searched online and found some possible solutions, including printing one of the designs myself. To colorize the filament, I used marker pens, but on my first attempt, it did not work well - the ink was layered unevenly and the felt tip got stuck in the hole. Additionally, the markers only printed on one side and bled color due to residue left behind. After that, I decided to try using old inkjet ink I had lying around, but unfortunately, it was limited to four colors: CMY and black. To test this method, I printed a project from Thingiverse - http://www.thingiverse.com/thing:190118 - cut a piece of dense sponge, added blue ink, and snapped it onto my white filament. Next time, I need to remember to wear gloves. The result was a light blue print that looked great. When I tried the same color on yellow filament, I got a nice green for the fan blades. This method colors the filament evenly on all sides. I want to try mixing different colors and see what happens.