Flexible Polymer for blade hub?

[Matrix1000]

I'm looking for a flexible yet stiff piece of something or other to use as a hub for my turbine blades for use with the downwind turbine design using hornet or jerry blades.

I'd like to find some kind of material that would be stiff enough to hold the blades out under normal operating conditions yet allow them to bend back slightly under high winds to shed wind. +<

I talked to Pohl Spring Works today and they mentioned 'blue clock' spring/steel.

Has anyone had any experience with this stuff, and would it be ok to use without having to worry about it cracking and throwing a blade in a year.

They also mentioned that some sort of polymer might be good but couldn't recommend any type specifically as they were unfamaliar with it.( I was thinking of plain rubber mud flaps or something a little thicker)

Is there anything that you can think of that would work for this purpose?

[gatu]

I am not sure if it would provide sufficient flexibility, but you could consider a deep mounting at the hub with a rubber block glued on each side of the blade, and the whole assembly bolted through the hub ring. By having bolt holes through the blade bigger than the bolts, the blade would rotate back as thrust increased. The flexibility of the system would be set by the stiffness and thickness of the rubber. An added advantage of the system would be that at high loading, the blade would tend to pitch regulate, reducing its aerodynamic efficiency, so reducing loads.

[Electric Ed]

I believe, in addition to the spring machanism, that you will need a linkage to ensure that all the blades deflect equally.

Electric Ed