Some tips for light helicopter swashplates / first of all you need three joint-point to control the swashplate (three points in space define a plane)/second - you need a minimum flight control movements so this points in direct link with the control rods need to be positioned an 90 degree - for minimum comand movements ( I supose you do not have a autopilot ).....heavy helico got 120 degree between controlpoints but they are provided with hidraulics and autopilot which manage the movements of swashplate as to tilt in accordance with the required axis.
If more info needed (axis of tilt and so on) contact me at codrea_d@yahoo.com