Those of you who have seen my earlier posts about my wind turbine no that I need a new and better set of blades. This past week I started that project with the purchase of 12 eight foot cedar 2x4 boards. Since this is my first attempt at blade carving I decided the best approach would be to do one blade completely from start to finish before working on the second and third. That way if I get it wrong then I've ruined one blade. The following is the sequence of work done so far.
The new blades will be just under five feet long for a machine slightly under 10' diameter. I used Alton's Blade Calculator for a TSR of 6. Pictured below is the stock wood laminated with West Marine epoxy.
Pictured below is the stock with an extra plank laminated on. It will give me some extra cord width at the root.
Pictured below is the stock with trailing edge taper cut away.
Starting to cut away everything that does not look like a blade.
Here finishing sanding with a belt sander in progress...
Here the front side shaping is complete. The brown "wet" area is epoxy mixed with sawdust that I had to use to fill in an area where the chisel cut too deeply. The extra epoxy will be sanded away. This is a mistake I'll be careful not to make on the other blades. Also there was a small void in the lamination at the tip I filled in with epoxy as well.
Here is another angle. I like this photo because it shows the "bowl" at the root where the drop is greatest. The front side shaping is complete. I've started rough cutting of the back side...
Here is the unfinished back side... Give me a couple more days and my first blade should be finished.
That's all so far. In a few days I hope to have the first blade complete.
Rob