Harmonics/Noise.
I'm not sure I agree with you Eoth. Can't any number can be spaced evenly around a circle? 6 blades is spaced every 60° and seven would be spaced every 51.4°
just like a 5-pointed star is generally evenly spaced.
Uh, that's right isn't it?
Geometry wasn't exactly my strong point, but that just stood out and made me think.
I do like the gap the odd number leaves though. Sure makes getting to those PITA bolts easier. A little...
Paul