RepRapPro has their Tricolour Mendel out. It is designed to work with three colours or three different plastics at the same time. They also plan future usage of electrically-conducting plastics, magnetic plastics and soluble support materials. Great to see that the technology is advancing. Hopefully first reviews of the working machine in real world applications will be out soon. It is priced around 1000 USD.
Specs:
http://reprappro.com/Tricolour_Mendel
Specs:
- Build volume: 210x190x140mm
- Overall size: 500x460x410mm
- Printing materials: ABS, PLA, 1.75mm diameter thermoplastic.
- Build surface: PCB-heated bed to reduce complexity of assembly and to ensure parts do not warp. Computer interface: USB
- X-carriage: Three Z-adjustable deposition heads.
- Accuracy: 0.1mm
- Resolution: 0.0125mm
- Building speed: 1,800 mm/min
- Moving speed: 12,000 mm/min
- Deposition rate: 33 cm3 / hr
- Motion: Linear ball bearings on X and Y axes, Igus low friction bushings on Z axis.
- Pre-soldered electronics with built-in microSD card slot for standalone printing.
- enhanced widely-used Marlin firmware allowes the addition of a slave controller board to drive the extra extruders.
- Arduino-compatible Melzi electronics for both the master and slave controllers.
http://reprappro.com/Tricolour_Mendel