Blade Materials
We have four blade materials now:
1) Wood ---- good for fatigue .... not so good for balance in a humid area. Getting hard to find clear wood but could be laminated from small pieces. A material called compreg is used for props, compreg is similar to paper sheets glued into a block then shaped.
2) Aluminum---- has lower fatigue life than steel but is often used.
3) Steel------ used in the past for autogyro and helo blades. I am considering steel for myself because of the weldability. I dont think steel could be used for a rigid rotor, most likely a teetering design will be used.
4) composite---- some materials absorb water and give balance problems. Materials are much more expensive and labor is more as well I think.
Anything else.... I think thats it for materials.