Is this a viable idea / why hasn’t it been done yet?
CNC milling machines have ability to simply change tools. Tools are parked somewhere in the milling area or in a separate chasis and the spindle can automatically pick up specific tools when needed.
Could you transfer the idea to 3D printing? You would have a carriage that could pick up different tool during printing. Tool would consist of extruder + hotend + nozzle. Tools would be parked somewhere in the printer. The XY holder would pick up the tool it needs and quickly switch to a different one.
Benefits over bowden + multiple nozzles:
- can have direct drive
- can have different extruders and hotends, each one suitable for particular filament or section in the print
Benefits over bowden + single nozzle:
- no retraction and priming on each filament change
- less wasted material
Unique new possibilities:
- pick and place head, for example for automatic insertion of metal or electronic parts
- nozzles of different diameters to optimise speed of printing
- complexity and reliability: need elegant mechanical solution for mounting and locking onto carriage.
- price: each tool would have it’s own extruder, hotend, etc. There is also additional mechanics for tool changing