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Splash Deflector versus Bow Submergence - Hey Tom Kirkman??
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Author:  FraznDaf [ Tue Mar 26, 2013 3:15 pm ]
Post subject:  Splash Deflector versus Bow Submergence - Hey Tom Kirkman??

Tom,

First of all, I APPLAUD your ingenuity and craftsmanship!!!!

Reading the posts about the large splash screens made of loose weave cloth,
some folks noted that the bow can submerge under a large swell, ususally going downwind. The problem seem to lie at the surface area of the cloth can PREVENT the bow from rising back up to the surface using postive bouyancy.
Soooo,,,,,,
Another post demo's a solid plastic Batwing concept that sits in front of the mast preventing splashes and holding the bow up as it buries nose down into a wave.
Folks opined that attaching a plastic wing to the bow can add lots of stress to the entire bow.
Sooo....... Can you envision a Split Wing installed behind the forward hatch that pivots on a horizontal mast in front and the back corners bungeed to the fwd crossbar??
IMAGINE 2 Right Triangles with the apex bolted to fabricated crossbar in front and having bungee on the bottom corners attached to the AMA CROSSBAR
This way as the forces get too strong on the wings - the bungee will give and spill water in either up or down direction, as the bow is burying or rising????
WHATCHATHINK????

Author:  Slaughter [ Tue Mar 26, 2013 10:01 pm ]
Post subject:  Re: Splash Deflector versus Bow Submergence - Hey Tom Kirkma

I get what you are suggesting and reckon that there is no reason why it wouldn't work. I do though, have to defend the splash guards and just correct a couple of your comments. I haven't used Bobs spray skirts so I can't really comment on their functionality. There are plenty of customers out there that will certainly defend them to the hilt with a lot more knowledge on them than me. The plastic splitter design is really aimed at 'splitting' a wave and reducing some of its power. It was never intended to hold water either above or below it but to flex and allow any excess forces, either up or down, to be deflected and pass. Without going through the treads again, I don't think there was ever any comment about it adding stresses to the bow ???? If there were, well I can categorically assure anyone attempting to make one that.... 'there isn't'.

I have used mine perhaps a dozen times now and would never be without it.

Author:  Tom Kirkman [ Wed Mar 27, 2013 4:30 am ]
Post subject:  Re: Splash Deflector versus Bow Submergence - Hey Tom Kirkma

I haven't made anything like that yet and so anything I offered would only be a guess at this point. As our weather improves and I'm back on the water more over the next few weeks I'll give it some thought and see what I can come up with.

Are you primarily wanting to prevent the splash that gets tossed back into the cockpit? If so there is something out there used in another application that no one has adapted to a boat yet. At least as far as I know. It breaks up water into tiny droplets in an instant, and deflects them. I need to take another look at it.

Author:  FraznDaf [ Wed Mar 27, 2013 7:46 am ]
Post subject:  Re: Splash Deflector versus Bow Submergence - Hey Tom Kirkma

Tom and Slaughter,
My Post compares 2 different problems w AI/TI bows - splash or spray hitting AMAs then deflecting into cockpit VS burying bows into wave troughs.

Some solutions to the first problem create a bigger second problem
I might have misunderstood some of the posts about the large mesh weave spray deflector.

I understood that it could hold the bow underwater a bit too long under a large wave
I then read about Slaughters design slicing thru a wave or flexing up/down in a large wave to shed the water force burying the bow. I thought folks worried about pressure on or near front hatch could distort it allowing large intrusion of water!

Others opined about Adding bouyancy to the bow thru xtra flotation or using water flow to raise the bow, especially going downwind on a windy day and burying the bow into a wave trough. ( another topic for sailors to chime in on "Surfing" waves thru a wave trough in the ocean-tricky!) I have had to lean backwards to hold bow up, even on a large lake in my TI going downwind w high winds - 15kts +

So my idea was to split a plastic wing, attached away fr hatch and mebbe solve the splash and submarine probs together??!!

Author:  cuda_kev [ Fri Mar 29, 2013 5:06 am ]
Post subject:  Re: Splash Deflector versus Bow Submergence - Hey Tom Kirkma

G'day all,

A few months back I purchased Shufoy's AI (with the custom anti-dive add-on from FINN), my first impressions were that it works great but I was concerned about the added stress at the attachment point. So currently I still have it fitted, but I have fashioned a backing plate to fit in side the bow hoping to distribute any additional loading.. i.e; not peeling the deck off the bow..

Author:  Tom Kirkman [ Fri Mar 29, 2013 12:55 pm ]
Post subject:  Re: Splash Deflector versus Bow Submergence - Hey Tom Kirkma

Okay, as the splash doesn't bother me (nor the submarining) I haven't given a great deal of thought to making any sort of splash guard for either my AI or TI. This afternoon I was piddling around back in the shop and decided to give it some thought. If I wanted to reduce the splash without adversely affecting the boat's ability to surface after plowing through or under a swell, here's what I'd do...

Think "bristles." Instead of a curtain, guard or spray fabric type of arrangement, think bristles - like the ones you'd find on the end of a push broom. (Synthetic bristles of course, as you don't want them to soak up water.)

You'd want them long enough that you could have enough length to block the majority of the water that comes straight back into the cockpit, although this may not require the length you might think. A few inches might do it. A slotted track running back from the bow on both sides of the hull, perhaps to the forward Ama area, would hold a strip of tightly bound bristles. While these would be sufficient to break up water splashes, they wouldn't overly impede the ability of the hull to resurface from underwater. They'd just flex downward.

I'd have to spend a day scrounging some parts and pieces to actually make one and try it (and I may do that just for kicks) but this is the route I'd take if I was going to try and tackle the issue. There'd be no moving parts. Nothing that stands much chance of breaking or being torn off, cost should be minimal and I'd expect it to be very effective.

Author:  davew [ Fri Mar 29, 2013 1:19 pm ]
Post subject:  Re: Splash Deflector versus Bow Submergence - Hey Tom Kirkma

The nosediving gives me a rush of impending disaster with the knowlege that the bow will rise eventually.

Author:  Slaughter [ Sun Mar 31, 2013 4:33 am ]
Post subject:  Re: Splash Deflector versus Bow Submergence - Hey Tom Kirkma

A beautiful piece of script Dave. Sounds like it was plucked from the tombstone of a AI sailor that nose dived once too often.

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