Thursday, February 20, 2014

USA 35b Air Foil

Silhouette of airfoil with 6 degree angle of attack shown.  Rectangle with thick black lines are 1.5" by 7.25"

It looks like the amount of whittling that needs to be done for my windmill blade(s) can be reduced if I can talk my good friend John into running the 2 X 8 through his planer and take three degrees off the bottom and 20 degrees off the top.

One other nicety will be if I can be smart about the warpage.  If I am lucky enough to get edge grain (quarter sawn) I won't have to think about warpage.  If I cannot get edge grain then  I think bark-side-down is preferred.  That will add some concavity to the bottom surface which is not a bad thing.

I mentioned to Kubota that I wanted to put up a wind turbine. 

"Oh, yeah, right.  Do you know how much those things cost?"

That is when I told him I was going to make it.  I got that look, you know the one.  It is the same one crazy people get when they claim they can spin straw into gold.

Any idiot can make a windmill.  It takes a special idiot to make a cheap and simple wind turbine that actually makes some power.


  1. Hell, the Dutch have been making them for years. Can't be much to it.

  2. Good point.

    I had further conversation with Kubota. It turned out that the only picture he had in his head were these

    I doubt that I could afford the structural steel -or- aluminum -or- the copper wire on one of those suckers.

    Making something that spins in the breeze is child's play. Heck, maple seeds have been doing it for millions of years before people showed up. The art and science is matching it to the load and sizing the components between the spinny thing and the load.