Wood Blades First Attempt

[adaml]

Hello all,

Please may I ask for you opinion as to whether I am heading in the right direction with regard to marking out and cutting my first set of wood blades.  The carpentry side is not too much of a problem for me but I struggle with the maths!!  I was hoping all you more educated folk might be able to look at the pics I have attached and give me your opinions?

Adams files are over here:

HERE

TW.

[luv2weld]

Adam,

I'm not doing too well today with mindreading.

Please tell us about your generator. Also you can

tell us what the math is that you are referring to.

How did you determine the dimensions of your blades???

Are you using a set of plans or is this your own creation??

Is this your first generator or have you built a generator

using a set of plans from either Hugh or the Dan's?

Give us some information and we will try to help.

Ralph

[adaml]

Sorry Ralph, common error on my part, being too vague!  

Motor is a 30v Ametek.

Figures are from the Alton Blade Calculator - dimension 1.321m, 3 blades, 5 stations, rest of figures left untouched.

Based dimension on the pvc set I am currently using of the same size which spin motor up fine, reach 300rpm in 5m/sec wind.

Plans are from Hugh Piggots blade carving tutorial.  Rest of mill is my own hotch-potch!

First attempt at wood blades, always used pvc before.

Never built generator, bit advanced for me yet..........in future hopefully.

I hope this is a bit clearer?

[valterra]

If the camera is looking at the Tip, with the Leading edge on the left, the Trailing on the right, the Front (wind-facing) face on top, and the Rear on the bottom....

that looks like you're on the right track, based upon my experiences.

It really isn't as hard as it may seem based upon the plans.  

One tip, if I could -

Where there are parts where the line runs off the board (or close to it) on the edges, in real life give yourself about 1/8 inch instead.  I ruined my first couple attempts by making kerfs that actually cut all the way down to the other edge (front face trailing edge near the root to be specific)

This bladeset:

http://picasaweb.google.com/jehmobile/WindGeneratorWoodBladesV02beta#

has been flying for the better part of a year with no troubles.  It spins up pretty nice considering all the mistakes I made.  Look closely at my trailing edge for my reasoning behind the 1/8" mentioned above.

[valterra]

clarification - "not that hard" if you have the right tools.  Me, I don't have access to a bandsaw anymore.  Now I'm stuck and have a hell of a time making blades.  Your mileage may vary.

That bladeset pictured is on a 40v Ametek.  It is 4' in diameter.

[adaml]

Thanks for your comments Valterra and the encouragement.  Will press on.  I have an old jig saw and a carving knife for shaping, think I may need to invest in more appropriate plain!  It's an interesting learning curve and enjoyable too!!

[luv2weld]

Forget the carving knife!!! That will take forever and

you will have blisters on top of blisters!!!

Before you start cutting, have you read everything you

can get your hands on about Blade Carving???

Here are a few links---- should keep you busy for a couple

of days. But, hopefully will help you understand the blade

calculating and carving process.

http://www.windstuffnow.com/main/blade_design.htm

Windstuff Now  Blade Layout and Carving    NOTE: This is a pdf. You must have Adobe Reader.

http://www.windstuffnow.com/Blade-layout.pdf

Blade Design Help

http://www.windstuffnow.com/main/blade_design_help.htm

http://users.aber.ac.uk/iri/WIND/TECH/WPcourse/index.html

http://www.windmission.dk/workshop/BasicBladeDesign/bladedesign.html

http://www.ndsu.nodak.edu/ndsu/klemen/Build_Your_Own_Turbine.htm

http://www.builditsolar.com/Projects/Wind/wind.htm

Blade Carving 101

http://www.fieldlines.com/story/2007/3/8/13649/79230

How to Carve Blades with a Chainsaw

http://www.fieldlines.com/story/2008/8/4/105522/4890

And if you want to carve a blade by hand, try this instead of

the carving knife. Really a nice tool to have for carving blades.

http://www.baileysonline.com/itemdetail.asp?item=15707&catID=

Ralph

[adaml]

Thanks Ralf,

Yes most of those I have already read and re-read, esp the Windstuffnow ones, that is what I am going by.  Will keep reading though!!  Thank you again.