Jerry;
So glad we could get you on the new board I know I really appreciate your input on a regular basis.
Right now its all by observation and my observations are that it runs faster than either stock or mike modded but its still rough with no knife edge on that trailing edge. I'll measure it later on for the precise dimensions of the cuts.
It was just what looked good and I free handed the first one with a razor knife and just copied it on the second.
The measurements from memory are 1.5" wide at tip with leading edge left stock. I started that radius from the root about 7" out from the point on the root section edge the radius is smooth from there to 1/2 the width of the blade at like 14 inches. then tapered to 1.5 inches on the tip.
I am fairly certain that the trailing edge being rough is impeding performance some. I don't have accurate measurement gear hooked up but we have reported 8 mph winds and mounted on my truck in the field putting out 20 volts from that 30 volt tape drive motor and will do 4 amps into a short before it slows down to a crawl. Diameter is 48" and they weigh 1.5 pounds including the arbor.
I am confident that dressing the trailiing edge to a knife edge would improve performance a lot because it wooshes while spinning. A slight radius on the tips might improve performance also.
Still got 8 blades to play with to see if these thinner blades can be gotten up to higher rpms for these tape drive motors at lower wind speeds.
Have you tried cutting these blades with a hot wire cutter or other means besides saw and razor knife?
Cheers.
TomW
