I'm totally mew to the vawt club so I'm still learning and I've learned a few thing here. I think three is probably going to prove better than two. This thing only has a TSR of about .7 so it needs a total redesign. I think the blades are too big and the venturi is in the wrong spot on the upwind side. I think I need to keep the air flow to the outside of the rotor on the upwind side till it comes past 90 degrees or it creates too much drag and the negative pressure behind the unit is wreaking havoc in the two blade design. The ropatec handles things a bit differently but I think some of the same problems may exist there too although I'm starting to see the merit in the delta and the football for the three and two blade designs.

BTW Xray that's a very fine unit you built.

I'm about to post drawings of my next learning experience with links back to the former posts so plaese give me your thoughts.