Multicolor 3D printers have been around for a while, but most of these machines – like the Makerbot Replicator – suffer from alignment problems and the inability to mix colors on the fly. [RichRap] came up with an interesting solution to this problem by having three filament extruders feed into a single hot end, allowing him to change and mix colors on the fly.
To print in multiple colors, [RichRap] developed a three-extruder x carriage that sends colored filament to a single hot end. Unlike the Makerbot Replicator, [Rich]’s extruder can mix and blend different colors into each layer of a print.
The electronics portion of the build, [RichRap] controlled the X, Y, and Z axes of his printer with a RAMPS board, but used a slightly modified Sanguinololu board for the extruder motors. A single motor driver for the extruders is connected to a trio of toggle switches, allowing [RichRap] to switch between filaments on the fly.
[Rich] has a very cool build on his hands, but it’s far from a perfect solution. Right now, any one of the three colors can be used to print, but printing with two or three colors simultaneously requires a change in the firmware. We expect someone to solve this problem in the near future, allowing the holy grail of a CMYK print head to come to fruition.
You can see a demo video of [RichRap]’s tri-color print head after the break.