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PostPosted: Wed Sep 13, 2017 6:33 am 
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mswlogo wrote:
How about making them out of the same cloth Bob uses on his splash guards.

Just enough to deflect most water but porous enough that water will fall through if it dives.


A wavedeflector (se previous pic int post above) must be solid to keep its hydrodynamic properties so a flexible material or fabric is not an option.

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PostPosted: Wed Sep 13, 2017 6:44 am 
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Wow! I have a hard time understanding what waves you are deflecting with a duckbill type deflector. After all the negative comments here, especially by KayakingBob, who has done the research, I would think the idea would be laid to rest. Not the case, I guess.

Keith

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PostPosted: Wed Sep 13, 2017 7:02 am 
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Chekika wrote:
Wow! I have a hard time understanding what waves you are deflecting with a duckbill type deflector. After all the negative comments here, especially by KayakingBob, who has done the research, I would think the idea would be laid to rest. Not the case, I guess.

Keith



We have weird waters here in the strait between Sweden and Denmark. Choppy short deep swells, often up to a bit more then 1 meter high (3-4 feet) but very short around 3-4 meters often combined with a 2-3 knot current. These swells really get you "stuck" so a wave deflector (duckbill) might help to keep the nose up.
I am very happy for all ideas and comments. KayakBob has given me some good pointers as well as you to. But as I understand none of you has tried this kind of wave deflector??
So I still think its an idea that has to be fully explored and that might improve the handling of my TI in theese choppy deep swells.
Ohhh yes... I am very persistent... LOL!
:mrgreen:

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PostPosted: Wed Sep 13, 2017 7:16 am 
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KayakingBob wrote:
...The Sprayskirt looked nice, but was so impracticable in strong wind. Also whenever it dove, it refused to surface until all forward motion stopped. I finally destroyed it.

KB's comment about "...refused to surface until all forward motion stopped" is the one you need to worry about. If you have enough speed and the bow stops, then the thing you have to worry about is the stern not stopping...in other words, pitch-poling is next.

No, since that solid type wave deflector is not available, we have not tried it. But, KB has lots of experience and my experience has been with a DIY spray deflector given to me by a friend. It was solid cloth. Like KB observed, once it dove, it seemed like it was never going to come back up...until my boat essentially came to a stop. In rough waters, your bow dives regularly. A solid, duckbill wave deflector (again, what waves that far forward?) could be a liability. Not much good in that.

Keith

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PostPosted: Wed Sep 13, 2017 8:30 am 
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Chekika wrote:
KayakingBob wrote:
...The Sprayskirt looked nice, but was so impracticable in strong wind. Also whenever it dove, it refused to surface until all forward motion stopped. I finally destroyed it.

KB's comment about "...refused to surface until all forward motion stopped" is the one you need to worry about. If you have enough speed and the bow stops, then the thing you have to worry about is the stern not stopping...in other words, pitch-poling is next.

No, since that solid type wave deflector is not available, we have not tried it. But, KB has lots of experience and my experience has been with a DIY spray deflector given to me by a friend. It was solid cloth. Like KB observed, once it dove, it seemed like it was never going to come back up...until my boat essentially came to a stop. In rough waters, your bow dives regularly. A solid, duckbill wave deflector (again, what waves that far forward?) could be a liability. Not much good in that.

Keith


Well Keith, this is the way I see the function of the upward pointning "hard" wave deflector in the bow:
The forward motion of the kayak (sail/motor/surf) will help the nose to surface much faster and get through the wave better. That is just logical.

I have lots of respect for the experiance you guys have from sailing the AI/TI (me/myself I am still a newb) but you surely arent very positive toward testing new ideas...
Seeing is believing. The vids that I have seen on YouTube with AI sailing BIG surfs with the "duckbill" do not give any indication that your concerns are very valid.
So I really have to give this a try... ! :D
I will get this "duckbill" modification done in the future (winterproject) .... Maybe it really works like a charm. Maybe its a waist of time... But it sure looks cool nevertheless! LOL!

Oh yes... like herpes... very persistent!
:mrgreen:

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Last edited by Husse0416 on Wed Sep 13, 2017 10:46 am, edited 1 time in total.

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PostPosted: Wed Sep 13, 2017 9:13 am 
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We all sail in different waters and to a different drummer. Good luck.

Keith

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PostPosted: Wed Sep 13, 2017 10:37 am 
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Chekika wrote:
We all sail in different waters and to a different drummer. Good luck.

Keith


I will ask my mates to post my obituary in the forum if I fail!
:lol:
Seriously I am still very optimistic to try this out but its lots of work to fabricate a final "good looking" product so at first I will try some sort of simpler prototype. Maybe an aluminium skid bent into the right shape will do? :roll:
Goto find a way to fasten the prototype without drilling holes in the bow. I wonder if a couple of ratchet straps would work for a shorter testride? Worst case it will come loose and sink and you can all have a good laugh on my behalf! :lol:
"My treat!"

Anyway its an interesting project. Just the sort of thing my curiosity needs. It might just give us all some new insights.
I was accually thinking of 3D printing the second version if the prototype seems to work.
Goto check the cost for such a big "print". (I have really no idea what the cost could be for that)
..... and I still very much like the idea to integrate a furler for a jib ontop of the "ducksbill"!
:mrgreen:
Qack qack!

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PostPosted: Wed Sep 13, 2017 10:48 am 
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"I mean it sort of seems to work fine..."






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PostPosted: Wed Sep 13, 2017 11:26 am 
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As long as it's angled up enough it should work. Videos certainly show it can work. Accept that little incident at 3:30 on the first video :)

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PostPosted: Wed Sep 13, 2017 3:00 pm 
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mswlogo wrote:
As long as it's angled up enough it should work. Videos certainly show it can work. Accept that little incident at 3:30 on the first video :)


I really think the "incident" at 3:30 very clearly shows that the concern of toppling over or totaly submerging as an effect of the wave deflector is totally unjustified. The AI works itself through the wave upwards and comes out just fine in the end just because of the wave deflector. Without the "duckbill" I can surely suspect the AI would have dived even deeper and then maybe rolled or toppled over as is would have loost speed and got sideways in the surf. To keep up the momentum and some speed is imperative to have rudder control.
Theese videos are shot with a light stock AI without much gear aboard at all.
So the duckbill might work very differently with my own "overloaded" TI with a total weight maybe 3-4 times that of the stock AI.
But my intent is not to take my own TI surfing, I just want a safer ride. :)

Anyway the vids clearly shows the duckbill in action, very inspiring!
Great vids! Big thanks to Mat Coburn
:)

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Last edited by Husse0416 on Wed Sep 13, 2017 10:19 pm, edited 1 time in total.

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PostPosted: Wed Sep 13, 2017 9:43 pm 
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The "incident" at 3:30 is simply the Island broaching. It has nothing to do with diving or pitch poling. Broaching is when a boat, coming down a wave, reaches the bottom, the wave trough. Of course, the bow reaches first and slows greatly. The stern, traveling faster, tends to turn sideways to the wave. It is called "broaching." It represents a danger to the boat because the boat is now sideways to the wave and may possibly be tipped over--sideways. A simple kayak or an Island in kayak mode would be in great danger when broaching. It takes a skilled paddler to prevent capsize in a broach. The Island with its aka/amas stays upright in the video. If the broaching occurs in shallow water, like at a beach, considerable damage could be done to the AI/TI as the wave slams it sideways into the beach.

Keith

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PostPosted: Wed Sep 13, 2017 9:57 pm 
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Chekika wrote:
The "incident" at 3:30 is simply the Island broaching. It has nothing to do with diving or pitch poling. Broaching is when a boat, coming down a wave, reaches the bottom, the wave trough. Of course, the bow reaches first and slows greatly. The stern, traveling faster, tends to turn sideways to the wave. It is called "broaching." It represents a danger to the boat because the boat is now sideways to the wave and may possibly be tipped over--sideways. A simple kayak or an Island in kayak mode would be in great danger when broaching. It takes a skilled paddler to prevent capsize in a broach. The Island with its aka/amas stays upright in the video. If the broaching occurs in shallow water, like at a beach, considerable damage could be done to the AI/TI as the wave slams it sideways into the beach.

Keith


Well I get that Keith but I still dont believe a wave deflector of this kind would increase the risk of pitch poling on the contrary it will help the bow to surface faster and avoid the risk instead. And going downwind or very fast if the conditions are that rough that the risk is eminent for poling I would probalbly have the sail furled 2/3 or more anyway.
But I do apreciate your concerns for thinking safe...
All the best!
/Gustav

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PostPosted: Thu Sep 14, 2017 2:50 am 
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I guess the ideal, if hard to make would be a "louvre" arrangement with slats angled up 45 degrees, water cant spray upwards yet if submerged it would offer minimal resistance to rise through the water. Something like that would probably have to be moulded whole rather than made up, so a DIY version would be difficult to make


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PostPosted: Thu Sep 14, 2017 3:29 am 
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WAVERIDER wrote:
I guess the ideal, if hard to make would be a "louvre" arrangement with slats angled up 45 degrees, water cant spray upwards yet if submerged it would offer minimal resistance to rise through the water. Something like that would probably have to be moulded whole rather than made up, so a DIY version would be difficult to make


The final version will be made in g/f resin or carbon but to develop and to try this out will take time and be made in at least three or four steps.
1. Very simple prototyoe wood or aluminium. Temporary strapped on to the bow.
2. After messuring and designing the furling jib/spinnaker I will make a base mount on the bow that will also serve as a fixing point for the wavedeflector.
3. Then i wilm make a mould of the entire bow so I can do resin casts and try different designs to ge the right hydrdynamic effect.
4. After finishing the design it will be laserscanned and then new moulds fabricated for vacum molding it with g/f or carbon.
So its a slow process running at least in about 2 years time total.
Next fall I hope I have some data and results from test with the first prototypes. Maybe the wave deflector will be very ineffective on the larger heavier TI (that is accually my biggest concern). But it shure seems to work on the AI.
Please notice that this is and will continue as a hobby project. I am not a professional boat designer so I set my standards at a hobby level. Usually my work is fine, sometimes a big fail and occasionally a real sucess.
If the results and design of the wavedeflector would work really well I will of course make it avaliable for purchase but this is not my motive to do this and we are still a long way from any of this.

Once I get this project going I will keep you all updated with the progress (or lack of it).
/Gustav

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PostPosted: Thu Sep 14, 2017 6:53 am 
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Curious where you sit on the TI?

I mostly sail on lakes which could have smaller swell but I sit in the back seat when solo and pretty much never have the bow submerge. Even with two people (lighter one in the front), I still really never have the bow go under. Even though its lake sailing, I have done some downwind sailing in fairly big swell and the TI sailed from the back seat just rides over the swell.

So I dont really have any problem to solve where I would need something like this but maybe that is dependent on where you sit. On my 2010 AI, I did have a problem with the bow punching through waves and sometimes submarining - almost capsizing. My opinion.. the TI sailed from the rear seat just doesnt need anything like this.


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