As RepRap has evolved it has acquired many tools and capabilities which have been developed and refined.Mostly this has been concentrated around plastic extrusion but tools exist for paste, metal, ink etc The next logical step in it's evolution would be to combine these capabilities to unlock further potential. Work is already ongoing on lots of multiple extruder designs on a single carriage. This is one potential solution. However I propose a Tool Changer!This is a work in progress and I will add more info as and when I get time.**First test of head changinghttp://youtu.be/-p9uMt9foKE**NEW Update nearly time to press printClose up of new extruder design and x carriage with sprung electrical connections.http://youtu.be/2qtQg9IiP5QWatch this space