Improving those Chinese blades

[gizmo]

In Oz we can pick up the 200 Watt Bergey clone windmills for less than $400, and a set of the fibreglass blades for only $120, or less if you scope out ebay. But these windmills are gaining a reputation of noise, lots of it.





I wanted to see if I could use these fibreglass blades as a cheap turbine for my F&P based windmills, so I ordered in 3 blades and set about making a few changes to reduce the noise. The blades are 1020mm long, and with extenders could make a turbine 2.2m or more in diameter, perfect for the F&P motor.

The modifications I made gave more power, but noise was proving to be a problem until I read a story here on Fieldlines http://www.fieldlines.com/story/2007/3/28/205619/172

I made a similar modification to my Chinese blades and it worked!





I've written up a full article about the modifications, so if you have one of these Chinese windmills and want more power and/or less noise, or just want to use the blades for your own windmill, then this might help.

http://www.thebackshed.com/windmill/articles/ChineseBlades.asp

Glenn

[CmeBREW]

Thanks Gizmo!

     I also GREATLY appreciate you and Electonbaby sharing this very nice little trick. I think most everyone will try this especially those with smaller windmills that make that horrible wirling noise. I know they outlaw windmills in many locations exactly for that reason. I hope this eventually over-turns those rules and laws. I can't wait to try this on all my future mills.  -Nice website--Very good instructions. Thanks!

[Slingshot]

Glenn,

I read through your article, but you did not mention whether there was any observable impact on output (better, worse, or perhaps just shifted the powerband) after you glued on the weedeater line.

[Norm]

I haven't had a noise problem ....don't usually

have enough wind or high enough tip ratio...

but looking ahead I may have someday and this

little trick would be nice to know....thanks for

sharing....

                 ( :>) Norm.

[gizmo]

Hi Slingshot.

When David ( who was testing the blades ) added the weed eater cord, held in place with tape, he said he didnt notice any change in performance. I'm sure there would be some, either good or bad, but it looks like its undetectable without the right equipment. My only regret is I dont have any good wind here for the next few months so I cant give any accurate power figures.

Glenn