mm123521
01-01-2012, 07:54 PM
All,
I built a twin electric outrigger this summer.
As most of you know, there is a limited number of props available in right and left rotation.
I have been cutting down 457's to various diameters between 50mm and 56mm, then cupping the trailing edge, with good success.
Now, I want more center-of-blade pitch, and have been experimenting with bending the entire blade, not just a trailing edge cup.
Check out the pictures.
I built an aluminum block with a cavity cut into it.
I filled the cavity with a low temperature (175 degrees F) fixturing alloy.
Then cast the whole blade into the fixturing alloy.
Then bend the whole blade close in to the hub, using an adjustable wrench.
Then melt the prop out of the fixturing alloy.
This procedure preserves the basic shape of the blade, while it gets bent.
The pictured 457 was 3.3 inches pitch, now its 3.87 inch.
I wonder if it will work OK?? Gotta wait till the spring, the water is frozen right now.
If you look at the middle picture closely, you can see a slight bend near the hub.
So far, I Have a pair of 457's cut down to 51MM with 4.0 inches pitch and a pair 55MM and 3.87 pitch.
What say, all you prop guy's, will this work?
Looking for 100MPH with a 16 pound, twin outrigger, 6S, 1800KVA, running near 40,000 RPM.
Mark
I built a twin electric outrigger this summer.
As most of you know, there is a limited number of props available in right and left rotation.
I have been cutting down 457's to various diameters between 50mm and 56mm, then cupping the trailing edge, with good success.
Now, I want more center-of-blade pitch, and have been experimenting with bending the entire blade, not just a trailing edge cup.
Check out the pictures.
I built an aluminum block with a cavity cut into it.
I filled the cavity with a low temperature (175 degrees F) fixturing alloy.
Then cast the whole blade into the fixturing alloy.
Then bend the whole blade close in to the hub, using an adjustable wrench.
Then melt the prop out of the fixturing alloy.
This procedure preserves the basic shape of the blade, while it gets bent.
The pictured 457 was 3.3 inches pitch, now its 3.87 inch.
I wonder if it will work OK?? Gotta wait till the spring, the water is frozen right now.
If you look at the middle picture closely, you can see a slight bend near the hub.
So far, I Have a pair of 457's cut down to 51MM with 4.0 inches pitch and a pair 55MM and 3.87 pitch.
What say, all you prop guy's, will this work?
Looking for 100MPH with a 16 pound, twin outrigger, 6S, 1800KVA, running near 40,000 RPM.
Mark