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Re: Shop: increasing initial stability
By:Paul G. Jacobson
Date: 5/9/2008, 1:47 am
In Response To: Shop: increasing initial stability (PatrickC)

: To increase initial stability on an existing kayak...what would you
: recommend?
: I thought about an add on "skin" that would make the sides flare
: out 30 degrees....they would be 6 feet long maybe 7" wide..centered
: on the paddler...probably made of closed cell foam with a thin backing
: with the ends tapered sharply for clean entry.

: any other suggestions? These are to increase initial stability a bit while
: fishing.

Anything you add to the width of your boat, which is below the water line, is going to increase the drag. Adding 6 or 7 inches on each side makes the width 12 to 14 inches wider. That is a lot of drag, and, it will affect the ability of the boat to track.

Anything you add above the water line will have no effect until it gets wet and starts displacing some water. So you can be rocking quite a bit (no added stability there!) before your additions take effect.

What you need is something that is in the water at the time you want the added stability, and out of the water when you want to paddle.

Any kind of outrigger will add stability. The bigger the thing is (greater displacement) and the further it is located from the centerline of your boat, the greater the effect.

You've already seen how shifting a weight some distance affects the leecocking of your boat when you used that 15 pound dumbell. Now consider something that would displace about 15 pounds of water (roughly a volume of 1/4 of a cubic foot) This doesn't have to actually weigh 15 pounds. It can be something as light as a fraction of an ounce, (so it can be easy to carry) just as long as it has the necessary volume. Think about a 1 gallon ziplock plastic bag. Open it, a gently puff into it, and zip it shut. You have a gallon of air trapped inside, and it will displace a gallon of water, or about 8 pounds.

Such a plastic bag may be too fragile for regular use, though. Instead, look at an inexpensive drybag. They frequently are sold by the volume they can contain. Open it, shake it out a bit and it will fill about halfway with air. Close it and tie it to the end of a spare paddle, or a cheap 2x4.

Mount the other end of this stick to your deck (other posters have suggested ways to do this, so I won't repeat that) and you'll have something as stable as a raft--and as sluggish to paddle if you try to do so with the float in the water. Get it out of the water (stow it on the deck) and your paddling will be normal.

This greatly improves your stability to one side, so shift your body weight a bit toward the outrigger. Or, use an outrigger on both sides of the boat.

This is an inflatable float that you don't have to pump up. It will be soft and saggy, but it will displace water and keep you stable. Of course if you want to huff and puff you can use a tube to inflate the thing until it is rigid, but for your purpose that isn't needed. To deflate it for storage, open it, and roll it up.

For something rigid and quick to make, get a piece of 4 inch drainpipe and two end caps. Either PVC or ABS will work. The longer the piece the greater the displacement. Mount it to a 2x4 so it forms a "T" shape, then mount the other end of the 2x4 to your boat and have the pipe line up parallel to the centerline of your boat. When you are not using this as an outrigger, it makes a good storage case for your fishing rods.

Just some thoughts. Good luck with your outrigger

PGJ

Messages In This Thread

Shop: increasing initial stability
PatrickC -- 5/3/2008, 9:58 pm
Re: Shop: increasing initial stability------WebKit *Pic*
PatrickC------WebKitFormBoundaryuhMQ6B+zsJB83qWB -- 6/22/2009, 10:32 pm
Re: Shop: increasing initial stability------WebKit
Bill Hamm -- 6/23/2009, 1:28 am
Re: Shop: increasing initial stability
Paul G. Jacobson -- 5/9/2008, 1:47 am
Re: Shop: increasing initial stability
Fred G -- 5/5/2008, 8:12 am
Re: Shop: increasing initial stability
PatrickC -- 5/5/2008, 9:55 am
Re: Shop: increasing initial stability
Fred G -- 5/5/2008, 4:23 pm
Re: Shop: increasing initial stability
Mike Savage -- 5/5/2008, 7:00 pm
Re: Shop: increasing initial stability
prasad bhatla -- 5/8/2008, 3:00 am
Re: Shop: increasing initial stability
JohnK -- 5/4/2008, 6:42 pm
Leeboards?
vk1nf -- 5/4/2008, 7:28 pm
Re: Leeboards?
JohnK -- 5/4/2008, 7:55 pm
Re: Shop: increasing initial stability
mike allen -- 5/4/2008, 3:32 pm
Re: Shop: increasing initial stability
Mike Scarborough -- 5/4/2008, 10:37 am
Re: Shop: increasing initial stability
PatrickC -- 5/4/2008, 11:04 am
Re: Shop: increasing initial stability
kent LeBoutillier -- 5/4/2008, 9:54 am
Re: Shop: increasing initial stability
Rob Macks / Laughing Loon CC&K -- 5/4/2008, 9:49 am
Re: Shop: increasing initial stability
Kudzu -- 5/4/2008, 9:00 am
Re: Shop: increasing initial stability
Brian Nystrom -- 5/4/2008, 7:58 am
Re: Shop: increasing initial stability
Bill Hamm -- 5/4/2008, 2:45 am
Re: Shop: increasing initial stability
PatrickC -- 5/4/2008, 10:27 am
Re: Shop: increasing initial stability
Nick Schade - Guillemot Kayaks -- 5/5/2008, 9:34 am
Re: Shop: increasing initial stability
PatrickC -- 5/5/2008, 10:32 am
Re: Shop: increasing initial stability
Kent LeBoutillier -- 5/5/2008, 11:49 am
Re: Shop: increasing initial stability
Thomas Duncan -- 5/5/2008, 12:35 pm
Re: Shop: increasing initial stability
Bill Hamm -- 5/5/2008, 1:56 am
Re: Shop: increasing initial stability
Craig Robinson -- 6/23/2009, 2:08 am
Re: Shop: increasing initial stability
Paul G. Jacobson -- 6/23/2009, 5:15 am
Re: Shop: increasing initial stability
Charlie -- 5/4/2008, 2:48 pm
Re: Shop: increasing initial stability
Rob Macks / Laughing Loon CC&K -- 5/4/2008, 11:21 am
Re: Shop: increase initial stability..test result
PatrickC -- 5/4/2008, 9:20 pm
Re: Shop: increase initial stability..test result
Rob Macks / Laughing Loon CC&K -- 5/5/2008, 9:35 am
Re: Shop: increase initial stability..test result
PatrickC -- 5/5/2008, 10:13 am
Re: Shop: increase initial stability..test result
Dave Houser -- 6/23/2009, 3:34 pm