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 Post subject: Re: DIY Home Made wooden Hydrofoil fins
PostPosted: Sat Mar 08, 2014 2:43 am 
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You might want to use large metal washers on the screw holes, the bamboo seem to get compressed more than other material.


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 Post subject: Re: DIY Home Made wooden Hydrofoil fins
PostPosted: Sat Mar 08, 2014 3:40 pm 
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Windfreak74,
Your foil is looking great!

To answer your questions:
>>when you mean 7% root is because you used half of the eppler 817 profile?
>>what i mean is if you used the upper half of the wing with a camber and a flat bottom (asimetrical).

7% means the eppler 817 profile was reduced in thickness from the standard 13.5% cord / thickness to 7% cord / thickness. It still maintains the full profile shape top and bottom (milled on both sides)


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 Post subject: Re: DIY Home Made wooden Hydrofoil fins
PostPosted: Sat Mar 22, 2014 3:36 pm 
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Location: Chile/Brasil
tried my foil for the first time.
i floats and board is always layed sideways on the wáter.
dont know if this is good just a observation.
wind was 8 to 10 knots with a 17 meter kite.
walked up to waist high deep wáter and tried my first tack
got up on the board and felt the beggining of lift the board popped out of the wáter.
did a canguroo hop and fell.
funny feeling!
wind did not help but i tried again same happend but i glided about 2 meters and fell to the side.
i could feel the foil pushing up but i still cant figure the balance.
tried for half an hour more but the wind was too flukey and slow.
conclusión is that foiling in sub10 knots is fun. everyone should give it a try!!
im a happy camper waiting for my next sesión.
do you guys think flotation is a good thing for the foil?


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 Post subject: Re: DIY Home Made wooden Hydrofoil fins
PostPosted: Sat Mar 22, 2014 7:31 pm 
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Welcome to the club, floatations is good. That is the correct position to start. If it sinks, you will need to prop it up to start. Once you get comfortable, use smaller kite .


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 Post subject: Re: DIY Home Made wooden Hydrofoil fins
PostPosted: Wed Apr 16, 2014 2:29 am 
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Location: Chile/Brasil
Got to go again and i cant figure out the standing position on the foil.
I think that im positioning my back foot behind the mast and i always bob up and down!
well i have all easter weekend for riding so ill keep trying.

Ive recentry got my new carbón and fiberglass fabrics for my V2 foil
im thinking of building a Wood core mast (eppler 837) of 17 or 19mm thickness with (120 mmchord)

this is my programmed layup for a 19MM mast

1 layer 15 oz triaxial carbón 12k 0/60/60(1mm)
1 layer 6oz 0/90 carbón plain weave(0,25MM)
1 layer of 15 ozz Fiberglass +-45° (1mm)
1 layer of 15 oz Fiberglass +-45° (1mm)
1 layer of 15oz Fiberglass +-45° (1mm)
10mm bamboo core
1 layer of 15 ozz Fiberglass +-45° (1mm)
1 layer of 15 oz Fiberglass +-45° (1mm)
1 layer of 15oz Fiberglass +-45° (1mm)
1 layer 6oz 0/90 carbón plain weave(0,25MM)
1 layer 15 oz triaxial carbón 12k 0/60/60(1mm)
with this layup i will get an aproximate composite skin of 3 to 4mm on each side of the core.

i can take away one layer of 1 layer of 15 oz Fiberglass +-45° (1mm) on each side to get a 17MM profile.
Do you guys think is overkill?


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 Post subject: Re: DIY Home Made wooden Hydrofoil fins
PostPosted: Wed Apr 16, 2014 3:07 am 
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They say torsional stiffness is the most critical element so wouldnt you want more of the stiffer carbon fibers on the +/-45?


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 Post subject: Re: DIY Home Made wooden Hydrofoil fins
PostPosted: Wed Apr 16, 2014 8:29 am 
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That is about the right formula. I wouldn't make it a 17mm, unless it is more carbon than fiberglass.


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 Post subject: Re: DIY Home Made wooden Hydrofoil fins
PostPosted: Wed Apr 16, 2014 2:40 pm 
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Location: Chile/Brasil
My first mast had 22 mm core with 1 layer 6oz +-45° carbón 2x2 twill(0,25MM) and a
2 oz fiberglass layer.
No problem on longitudinal flex but more torsional flex.

Maybe this is better
2 layer 6oz +-45° carbón plain weave(0,5MM)
2 layer 15 oz triaxial carbón 12k 0/60/60(2mm)
1 layer of 15 ozz Fiberglass +-45° (1mm)
1 layer of 15 oz Fiberglass +-45° (1mm)
10 mm bamboo core
1 layer of 15 ozz Fiberglass +-45° (1mm)
1 layer of 15 oz Fiberglass +-45° (1mm)
2 layer 15 oz triaxial carbón 12k 0/60/60(2mm)
2 layer 6oz +-45° carbón plain weave(0,5 MM)

Somewhere in 18mm to 19mm range.
More carbón on the outside :thumb:


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 Post subject: Re: DIY Home Made wooden Hydrofoil fins
PostPosted: Wed Apr 16, 2014 7:03 pm 
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That would be strong for sure.


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 Post subject: Re: DIY Home Made wooden Hydrofoil fins
PostPosted: Tue May 06, 2014 2:28 am 
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Joined: Tue Mar 23, 2010 1:16 am
Posts: 366
Location: Chile/Brasil
Hello Hawaiis,
after all your R&D with the wooden hydrofoil Project i have questions
which part offer the most contributing factor in performance using Wood as main material
i mean which component or part do you think needs more refining?

if not one do you think is a balance(adjustments) on all parts to make a decent Wood foil experience?

after all your trials which simple material is better suited for each each part?

considering that the drag is higher on your wooden foil, does the drag part limits your ability to wáter start?
what is an average crusing speed on the wooden versión compared to your carafino mast/fuselaje?
thanks,
Pedro


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