Someone already did this, but I can't find the link. Four bladed teetering is really hard to to
because the two blade systems have to interlock but not touch each other.
It doesn't really have any advantages as regular flapping hinges do the
same thing on a 3 or 4 blade head. Teetering really only makes sense on two blades.
Blade area is not that critical, I'm flying a 1 pound model with
two little 1.5" x 16" blades and can fly fast and slow....