I don'y usuualy balance these small 4 ft blades. But what the @#*! I thought I'd just check this out.
What brought me to this point was my foam plastic pipe blades. It was very apairent from the beginning they were way out of ballance. My plastic "Jerry Blades" have allways run real smooth.
So I set up A 3/4" shaft and a pair of very free spinning bearings. You'll see in the picture the foam pipe blade has 1 blade with a slight bit of orange piant over spray (I got to close).
In the shaft jig the orange blade would allways settle pointing down. After fidling with some (black)washer weights I could set the orange blade in any position and it just stayed there. I'd give it a spin and it never stopped at the same place twice (YIPEE).
Well I did the same thing with a slightly out of ballance "Jerry Blade" .
Now out to the wind tunnel.
I just did a very quick no load open voltage test. I still had my littel duel rotor 8" jenny mounted in the tunnel. Its a 24 volt unit.
I set the mph to 11 for 4 test. Each blade twice. Once without ballance for each and once with ballance for each.
Pipe blades 11 mph out of ballance 20 volts.
Pipe blades 11 mph ballanced 30 volts.
Plastic "Jerry Blades" 11 mph out of ballance 40 volts.
Plastic "Jerry Blades" 11 mph ballanced 46 volts.
I'm very eager to check Hughs 4ft blades when my custom blade builder finnishes them.
It would seem there would be some effect on starup with out of ballance blades. Not so much on small blades but the big units?
Heres a couple pictures.
These are the foam pipe blades
Next the "Jerry Blades"
I'm not sure what effect ballance has on a loaded blade compaired to a free wheeling blade but I'm sure there both greatly effected.
You can see it din't take many washers to correct the inballance.
Jerry
