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Re: too light to drift downwind?

Posted: Fri Dec 28, 2018 5:33 pm
by Mossy 757
I have a full-carbon Delta hydrofoil that ALWAYS lands foil-down...I wouldn't say the floating on its side thing is a carbon foil issue, it sounds to me more like a "carbon over foam/wood core" issue. Also, the Delta is insanely light, so it's not even a weight thing, I think it's a buoyancy of the foil thing and since carbon isn't buoyant (but wood/foam cores are) again I'd just think carefully before buying a setup made with cost-cutting materials.

Re: too light to drift downwind?

Posted: Fri Dec 28, 2018 5:58 pm
by Peter_Frank
Mossy 757 wrote:
Fri Dec 28, 2018 5:33 pm
I have a full-carbon Delta hydrofoil that ALWAYS lands foil-down...I wouldn't say the floating on its side thing is a carbon foil issue, it sounds to me more like a "carbon over foam/wood core" issue. Also, the Delta is insanely light, so it's not even a weight thing, I think it's a buoyancy of the foil thing and since carbon isn't buoyant (but wood/foam cores are) again I'd just think carefully before buying a setup made with cost-cutting materials.

Hi Mossy, yes your deduction is immediately correct, but it is not.

I assume you havent got any of the 1000-1500 cm2 Surf wings right?

These DO have that much more buoyancy, without being soft or fragile, so because these are maybe the most used by non-racers now, this is a new thing not really apparent before.

Small board low volume, and huge surf wings - makes the hydrofoils sit on the side quite often now, compared to earlier.

I havent seen being impossible to retrieve my boards yes, but definitely a lot harder.

As I havent experienced NOT being able to retrieve my boards, I still love the stiff and lightweight foils we got today.

But yes, maybe if there IS a way to avoid this, it could be interesting?

8) Peter

Re: too light to drift downwind?

Posted: Fri Dec 28, 2018 6:19 pm
by Mossy 757
Peter_Frank wrote:
Fri Dec 28, 2018 5:58 pm
Mossy 757 wrote:
Fri Dec 28, 2018 5:33 pm
I have a full-carbon Delta hydrofoil that ALWAYS lands foil-down...I wouldn't say the floating on its side thing is a carbon foil issue, it sounds to me more like a "carbon over foam/wood core" issue. Also, the Delta is insanely light, so it's not even a weight thing, I think it's a buoyancy of the foil thing and since carbon isn't buoyant (but wood/foam cores are) again I'd just think carefully before buying a setup made with cost-cutting materials.

Hi Mossy, yes your deduction is immediately correct, but it is not.

I assume you havent got any of the 1000-1500 cm2 Surf wings right?

These DO have that much more buoyancy, without being soft or fragile, so because these are maybe the most used by non-racers now, this is a new thing not really apparent before.

Small board low volume, and huge surf wings - makes the hydrofoils sit on the side quite often now, compared to earlier.

I havent seen being impossible to retrieve my boards yes, but definitely a lot harder.

As I havent experienced NOT being able to retrieve my boards, I still love the stiff and lightweight foils we got today.

But yes, maybe if there IS a way to avoid this, it could be interesting?

8) Peter
I'm not saying it's impossible to make a durable foil with a foam or wood core, just that if your foil is all carbon it doesn't matter what it weighs...buoyancy isn't directly related to weigh 1:1. Carbon fiber doesn't float, so if your foil is all carbon fiber, it could way 1 ounce and it'd still sit foil-down in the water.

Re: too light to drift downwind?

Posted: Fri Dec 28, 2018 7:07 pm
by Peter_Frank
But that is not only the issue really...

My foils doesnt float - but because of the now more than double surface area wings, compared to earlier wings - and very small boards too, it is a fact that they end up in the wind board on its side quite often, simply because of the wing area alone, even if the foil alone sinks.

So it is not so easy to talk about sinking or not.

Besides, a REALLY good build is both light and stiff and strong and can be buoyant, especially if high volume/area :thumb:

On afterthought - I've got wings from 520 to 1200 cm2, and the bigger the wings, the more likely they are to be able to get "stuck" on the side, especially in higher winds,

So much in fact, that I would think that even a heavier alufoil with say a 1500 cm2 surf wing or similar, could get stuck - has anybody experienced this?

8) PF

Re: too light to drift downwind?

Posted: Fri Dec 28, 2018 11:25 pm
by Regis-de-giens
I also frequently experienced my hydrofoil laying on its side when using my large 1200cm2 which never appeared with my smaller wings. When using a low LD ratio kite in strong winds in can be challenging to body drag "backward" to catch the foil.
You can see an exemple in the following video at 4 : 20 (with a 4m beginner foil kite in 25-30 knots). It lasted about 2 minutes to recover my HF and after 1 minute lost with absolutelly no progress, I finally had to put the kite at zenith and swimm backward with my legs and hands ... both funny and not funny (assumimg more wind...) .In the video I have let the full sequence but accelerated 10 times for illustration . We can see the foil on the side all along , but sorry the resulting sequence is not comfortable to look at ... :oops:
https://youtu.be/GlrlCCfIVO4

Re: too light to drift downwind?

Posted: Fri Dec 28, 2018 11:43 pm
by slowboat
Definitely can happen with large heavy wings. A friend experienced this with a 2000cm2 wing

Re: too light to drift downwind?

Posted: Tue Jan 01, 2019 3:51 am
by fun2kite
Mate, which boards are less than 2kg? the light boards I have seen all around 2.5 kg.

Yes this problem of a board sitting on a side, is real and been discussed. It's quite common with Onda wing as it is very light and floaty wing.. just refuses to sink.
TARTAX wrote:
Tue Sep 25, 2018 10:17 pm
i had the same problem with moses onda 633.
but only with low volume and heavyboards with a skimboard like construction.with this kind of boards the rail gets deep in the water ,the foil works like a dagger,the board like a sail and it starts to go away.
with strong wind it goes fast...
but now with a very light board,carbon construction less than 2 kilos the rail doesn't sink so much: so the wind hitting the board makes the board to rotate downwind and doesn't go away anymore.
so my conclusion is that with floating foils the boards with an heavy and no volume construction gives this problem