I've been looking into a DIY wind machine for many years. The part that has put me off the most is making the blades. Now it seems easy enough to buy a set of professionally built blades with known specs for a decent price. Then build the rest of your turbine around them.
I have been eyeballing replacement blades for a whisper 100 wind turbine (900w rated), they were $160 a set for a 3 blade 7ft rotor (they just went up to $180). The company and one dealer haven't been helpful at all in trying to get efficiency and tsr specs. So I started looking on ebay, and was pleasantly surprised to see many sizes of new 3 blade fiberglass blades for much cheaper. Many specs are given.
Here are some examples.
6.8 ft 3 blade for $48
WindMax Low Startup 6.8FT Wind Turbine Generator Blades - eBay (item 170291377610 end time Feb-01-09 11:31:10 PST)
9.2ft for $50
3 Wind Turbine Generator Propeller Rotor Blades 9.2' - eBay (item 360121063576 end time Feb-01-09 12:46:14 PST)
10.5 ft $128 shipped
Low Speed PowerMax+105 Wind Turbine Blades 3 Rotors HUB - eBay (item 310114701126 end time Jan-16-09 23:10:02 PST)
10.6 ft 3 blade for $85
WINDMAX-10.5FT Low Start-up Speed Wind Generator Blades - eBay (item 360121045829 end time Feb-01-09 11:36:13 PST)
13.1ft for $180
WINDMAX 13.1 FT(4M) Wind Generator Blades Wind Turbine - eBay (item 360121050486 end time Feb-01-09 11:53:53 PST)
No need to carve your own at those prices IMO
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