Author Topic: 10ft Other Power build  (Read 515 times)

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FishH2o

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10ft Other Power build
« on: July 14, 2017, 03:00:27 PM »
Well after some small screws ups I decided to save my good long lumber for a future build. I have decided the best way to learn is building a version that is well documented and widely used. I will use this to document the build and ask for suggestions and advise. Thank in advance for all help and comments are greatly appreciated. I have my blade blanks all cut out and will post some pictures once I have them resized.

SparWeb

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Re: 10ft Other Power build
« Reply #1 on: July 14, 2017, 09:26:40 PM »
Cool
Looking forward to seeing it!
No one believes the theory except the one who developed it.  Everyone believes the experiment except the one who ran it.

System spec: 135w BP multicrystalline panels, regulated by Xantrex C40, DIY 8ft diameter wind turbine, regulated by Tri-Star TS60, 800AH x 24V AGM Battery, Xantrex SW4024

FishH2o

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Re: 10ft Other Power build
« Reply #2 on: July 15, 2017, 10:36:16 AM »
These are the 3 blade blanks I have cut down.

FishH2o

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Re: 10ft Other Power build
« Reply #3 on: July 15, 2017, 05:19:30 PM »
Question or you guys... So, 2 of the 3 boards were without warp. I leveled the root and checked the level at each station. Now, the third board, after I leveled the root the tailing edge is higher than the leading edge. The opposite, Hugh Pigott says to take the measurements with the help of the level raising it. My question, since the leading edge is lower than the trailing edge can I shave down the tailing edge with a plane to make it level before I take my drop measurements? Or, must I lower the level to compensate for the warp?


***Edit***
Or, does it mater as long as I do the same to each?

dnix71

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Re: 10ft Other Power build
« Reply #4 on: July 15, 2017, 06:34:06 PM »
The forces are at the tip of the blades. How close are the relative weights of the blades? If they weigh the same, a thin shim washer when mounting the warped blade would place its wing tip back in line with the other two. This means less material is removed. Balance the hub first, then mount the blades, rebalance adding weight near the hub and shim to make the tips travel in a clean circle. Uness the centers of the blades are way off it won't matter much as all the work is done near the leading edge.

SparWeb

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Re: 10ft Other Power build
« Reply #5 on: July 16, 2017, 08:57:05 PM »
Your third board does look like it has a twist in it, but let me go down to basics: You will have to accept unpredictable twists if you use solid boards with knots in them. 
Dealing with this now, this way, may be a bit of tail-chasing since these boards may be too fresh to be done drying yet.  They could continue to twist later.
That's the reason behind laminating wooden blades, which has been very good at stopping warpage in my blades.
I have lots of twisted lumber in my woodshed fine for building horse shelters but not so good for making WT blades.

To deal with the blades you're working on today, you could stick to getting the incidence angle of the tips the same on all 3.
Start by clamping the root ends of all 3 together in between two (flat) boards so that they're lined up like they would be on the hub.
Lay a straight edge along the tips, and use your protractor to check the angles of all 3.  With numbers we can judge how much work it will take to fix.
No one believes the theory except the one who developed it.  Everyone believes the experiment except the one who ran it.

System spec: 135w BP multicrystalline panels, regulated by Xantrex C40, DIY 8ft diameter wind turbine, regulated by Tri-Star TS60, 800AH x 24V AGM Battery, Xantrex SW4024

hiker

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Re: 10ft Other Power build
« Reply #6 on: July 16, 2017, 11:29:47 PM »
What about steam then clamp down to a flat surface ?
WILD in ALASKA

MattM

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Re: 10ft Other Power build
« Reply #7 on: July 17, 2017, 04:02:31 AM »
actually, you can use heat treatment without steam to get any desired permanent shape to wood.  You must seal them once they are heat treated to prevent further unintended warping, although you can expect very little.  Think kiln drying.  You need a form, preferably from metal, to give the desired shape.  And you have to be careful not to burn them up if you choose to use open flame, which is the easiest method.  Look up how skis are formed.

dnix71

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Re: 10ft Other Power build
« Reply #8 on: July 17, 2017, 04:57:49 PM »
If you can build a good ski, you can build a good blade. Like SparWeb said, lamination is the key to uniformity and stability.
http://www.skibuilders.com/howto/skicon/lamination.shtml

kitestrings

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Re: 10ft Other Power build
« Reply #9 on: July 18, 2017, 08:04:09 AM »
Those look like pressure treated 2-bys.  If so they are pretty green - both in color and moisture, or preservative content.  Like a deck, they will shrink, check and move quite a bit as they dry.  I think the idea of clamping or pressing them ideally until they can dry would be a good first step.

Good luck, ~ks