Things you need to know about a vane, or known as a tail in slang.
Just because you read it here does not mean it is the only way or necessarily the right way, it just means I have found it to work.
I make my Vanes out of 16 gauge metal.
I had the mathematic equations on here
at one time to help
figure an exact size for your vane to match with the mass and lift
coefficient of the rotor you were going to use, but it seemed to confuse
some people. So let me make it simple.
Figure out what shape you want for your vane to be, the traditional arrow style, or some creation you come up with on your own. You can make your Vane in wild shapes like the batman symbol, a heart on its side, a 1/2 circle, a boot, etc. It doesn't really matter as long as you maintain a slope on the leading edge side. The simplest and easiest to make is the arrow style.
Once you get the shape of your Vane made you are ready to cut
your boom to length. Make it long enough so that your Vane can
run full length down the boom for support.
Mount the boom to your generator so that your boom runs perpendicular (at a 90 degree angle) from the rotor and you have that part done
Or you can buy a cool looking one from TLG. (click here to see it).