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Re: DIY Home Made wooden Hydrofoil fins

Posted: Tue Nov 12, 2013 12:17 pm
by Hawaiis
Both wings have a very small positive lift profile.
The front wood fin has a flat bottom and a foil profile on top.
The rear titanium wing has a very small curve.

Re: DIY Home Made wooden Hydrofoil fins

Posted: Tue Nov 12, 2013 4:07 pm
by Bille
Hawaiis wrote: ...
The floor tile is 1 foot square, so you can see how big they are.
How much Bigger would you have made the foils, if Ya weighed
210lb , like me ?

Bille

Re: DIY Home Made wooden Hydrofoil fins

Posted: Tue Nov 12, 2013 6:18 pm
by zfennell
The rear titanium wing has a very small curve.
very cool.
I never realised that you cambered the aft foil.
how did you go about that?
is it set up for pos lift or neg lift?

thanks

Re: DIY Home Made wooden Hydrofoil fins

Posted: Tue Nov 12, 2013 7:57 pm
by Hawaiis
Bille wrote:
Hawaiis wrote: ...
The floor tile is 1 foot square, so you can see how big they are.
How much Bigger would you have made the foils, if Ya weighed
210lb , like me ?

Bille
The standard area is approximately 1 square foot for the front wing, I have experimented with1.2 to 0.6 square foot of different shape and size. I weight 145lb, if I weight 210lb, I would probably use 1.1 square foot as base.

Re: DIY Home Made wooden Hydrofoil fins

Posted: Tue Nov 12, 2013 8:03 pm
by Hawaiis
zfennell wrote:
The rear titanium wing has a very small curve.
very cool.
I never realised that you cambered the aft foil.
how did you go about that?
is it set up for pos lift or neg lift?

thanks
The titanium scraps I bought some came with cambering. I can bend them with heat too. The cambering did not have too much effect, since they are so small, I tried to mount it upside down and they don't feel any different.

Re: DIY Home Made wooden Hydrofoil fins

Posted: Tue Nov 12, 2013 10:43 pm
by kjorn
Hawaiis wrote:
zfennell wrote:
The rear titanium wing has a very small curve.
very cool.
I never realised that you cambered the aft foil.
how did you go about that?
is it set up for pos lift or neg lift?

thanks
The titanium scraps I bought some came with cambering. I can bend them with heat too. The cambering did not have too much effect, since they are so small, I tried to mount it upside down and they don't feel any different.
Yeah, I could imagine the tiny effect that the camber would have would be negligible compared to the action of the water, waves, your weight distribution and the kite all acting on the board.

Just by leaning back a little you will change the Angle of Attack way more than any neg/pos AoA of the back wing.

Re: DIY Home Made wooden Hydrofoil fins

Posted: Wed Nov 13, 2013 8:21 am
by BraCuru
Hawaiis wrote:
Looks like great fun! Impressive.
Would you make a small honest summary please?
How much did it cost you and how much time did it take to built?
Are you going to built another one?
Let us know when it breaks (how many hours on the water) and what (hope not!).
What is max speed and angles upwind, downwind with 10 and 20kts?

Re: DIY Home Made wooden Hydrofoil fins

Posted: Wed Nov 13, 2013 10:25 am
by Hawaiis
BraCuru:
I have been working on and off for the last 3 months, I have several in different stages of completion. Today the epoxy gluing the strut to the baseplate came loose, it was held by three screws, so it was just loose. I made another more robust base to hold the strut tonight.

Re: DIY Home Made wooden Hydrofoil fins

Posted: Wed Nov 13, 2013 1:02 pm
by BraCuru
Hawaiis wrote:I have been working on and off for the last 3 months, I have several in different stages of completion. Today the epoxy gluing the strut to the baseplate came loose, it was held by three screws, so it was just loose.
Thanks for sharing!
Did you count the total cost or have you been lost as me with my Bracuru Foilboards? :wink:
BTW.
What do you think to make a tuttle box in your design instead a pad mount? Probably it would be stronger in your case as it's difficult to make a pad and a mast from one piece of wood. :idea:

Re: DIY Home Made wooden Hydrofoil fins

Posted: Wed Nov 13, 2013 9:16 pm
by Hawaiis
The material cost is about $200 for the whole board and foil.
The one piece carved wood will not be as strong as one glued properly.
After the repair, the weight of the whole bottom unit is 2.55 kg
Compared to

MHL 3.7 kg
Carafino 4.35 kg
Rush Randle 5.5kg
MyWood 2.55 kg