There are plans available for "Al's Autogyro". It is a tractor design with coaxial, two-bladed rotors. Because the rotors are set up to be counter-rotating, there is no need for flapping blades, etc to offset centrifugal force problems or unbalanced lift forces. However, I built an "Al's Autogyro" according to the plans and found that one of the rotors would always be "lazy".

The two rotors could be interchanged and the one in one of the positions (top or bottom) would always just barely get rotating. I don't remember whether it was always the top or bottom one, but it always was the same location that was lazy.
As I recall it never did get off the ground.

Maybe it was my poor craftsmanship, but I really tried to get the thing to fly.

Bill