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A: Build boat; B: See A :)
By:Paul G. Jacobson
Date: 5/22/2001, 11:31 pm

: PAUL, I SEE YOU REASONING AND I HAVE HAD THE SAME ONE GOING BACK AND FORTH IN
: MY HEAD AND ALSO DRAWING ON PAPER TRYING TO SEE THIS. MY CANOE DID SPIN
: JUST AS YOU LOG DOES. BUT LOOK AT IT THIS WAY. IF YOU HAD A NARROW
: 20" WIDE KAYAK FLOODED WITH WATER BUT WITH SPONSORS ON EACH SIDE, YOU
: COULD PROBABLY CRAW OVER THE SPONSOR FROM THE SIDE AND BACK INTO THE YAK
: AND IT WOULDN'T SPIN AROUND IF THE SPONSOR WAS BIG ENOUGH.

I'll translate your "sponsors" for your "haul" for the rest of the board who are probably more familiar with solid or foam sponsons that go on the outside of the hull of a rigid kayak, or inflatable sponsons that go between the frame and the skin of a folding skin-on-frame kayak, like a Klepper or a modern Folbot. In all of these case the sponson effectively makes a wider hull, which makes he hull less likely to rotate. With the fabric skinned boats the internal sponson cna really make a profound change n the hull geometry.

: NOW PICTURE MY
: YAK AT 20" WIDE BUT WITH 4" WIDE SPONSORS ON EACH SIDE,

OK, you've demonstrated my point. The wood hull is 20 inche wide, but with an additional 4 inch sponson on each side the width of the hull is not only an effective 28 inches, but the shape of the crossection of the boat is radically changed. Your original boat has a cross section like a horizontal oval, but when you add the sponsons at the widest points on the sides of that oval, you get a shape that I can not label -- but it is significantly wider!.

: BUT ON
: THE INSIDE RATHER THEN THE OUTSIDE. OR THINK OF MY 28" WIDE YAK WITH
: AUTO TUBES TIED TO THE INSIDE UPPER SIDES OF MY YAK.

Whoa there. Let's get these numbers straight. Do you have a 20 inch wide kayak, or a 28 inch wide one? If the boat is 28 inches wide and you add 4 inch sponsons to each side you get a craft that is 36 inches wide. At this point it is less likely that the boat will flip when you try a side entry.

Now, if you put an innertube inside the boat it merely keeps out water, thus allowing the boat to float a bit higher. If you put the innertube outside of the kayak and tie it on, then it serves like an outrigger, and with the great flotation of an innertube (holding well over 100 pounds!)it is unlikely you could put enough of your body weight on the combination to ever get your boat to roll over.

: IF IT DOESN'T I STILL HAVE TWO WATERTIGHT COMPARTMENTS TO STORE CAMERAS,
: FIELDGLASSES, ETC.

Well, those should keep some of the boat above water even if it is filled.

: I SHOULD BE READY TO TEST IN A WEEK AND I WILL
: TEMPORARLY JUST STUFF A BASKET BALL IN THE STERN AND BOW FOR FLOATION.

Now there is an idea! Of course, since I have disagreed with almost everything you have planned I might as well weigh in with a volleyball and a net, instead. Those seem to attract more of the women on the beach :) and if you get marooned you cna catch fish with the volleyball net. (have I seen one episode too many of Survivor?)

: IT LOOKS LIKE I WILL HAVE TO UNSCREW THE SIDE HATCHES ON HOT DAYS TO VENT THE
: AIR PRESSURE ALSO.

Not a problem.

In fact, you could put a good sized hole in those bulkheads, say up to 1/2 inch in diameter, and not get much water in the holds. Put it at the top of the bulkhead, and if the boat is inverted during a roll the trapped air in the hold will keep water from gushing in. Just like pushing an inverted cup into a sink full of water. The air in the cup keeps the water out. open the hatch a crack and store the boat with the hull up ( the the hole is on the bottom) and any water in there drains out nicely and the holds dry up. Of course a smaller hole will let in less water in the first place. Or you can probably put in a hole and feed a piece of vinyl tubing through it, and point the hose down to the bottom of the kayak, stopping 2 inches above the bilge. Now the compartment can vent air, and if you roll the open end of the tube will be somewhere in the trapped air space in the inverted boat.

And a good sprayskirt will keep out even more water.

THANKS FOR YOUR THOUGHTS.

Hey, it's no problem to think up solutions, the hard part is actually building them -- and that's your job. Good luck with it.

PGJ

Messages In This Thread

Great Stuff Expanding Foam under Seat *Pic*
John Monfoe -- 5/17/2001, 5:32 pm
Re: Great Stuff Expanding Foam under Seat
Rick -- 5/20/2001, 11:33 am
Paul & Rick.
John Monfoe -- 5/21/2001, 6:50 am
A: Build boat; B: Try it out; C: Add flotation?
Paul G. Jacobson -- 5/21/2001, 10:18 pm
Re: A: Build boat; B: Try it out; C: Add flotation
John Monfoe -- 5/22/2001, 10:39 am
A: Build boat; B: See A :)
Paul G. Jacobson -- 5/22/2001, 11:31 pm
Re: A: Build boat; B: See A :) *Pic*
John Monfoe -- 5/23/2001, 6:25 am
Re: Great Stuff Expanding Foam under Seat
Paul G. Jacobson -- 5/17/2001, 11:55 pm
Re: Great Stuff Expanding Foam under Seat
John Monfoe -- 5/18/2001, 5:09 am
Expanding Foam elsewhere
Paul G. Jacobson -- 5/20/2001, 11:38 pm