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Re: How close to rear of coaming can seat be
By:Paul G. Jacobson
Date: 1/24/2002, 1:08 am

: My "model" shows me that I need to know now how close/far from the
: rear of the coaming the back of the seat rest has to be. If you build your
: own, can you put it as far back as you can as long as your back isn't
: hitting the rear of the coaming? Or is more room required here to
: practically make the seat comfortable in long use. Also is there a minumum
: space required for the spray skirt to have to be at least a certain size
: to the rear too (makes sense, but I don't know). And is it a good idea to
: figure the seat being as low as possible. Any information on spacing the
: seat properly within the cockpit ring is very welcome, thanks.

Gee, lots of questions and no data to work from.

So, in general, my take on the cockpit issue is that you darn well better have it located in exactly the right spot if you make it small and tight, because with a small cockpit you won't be able to wiggle very far fore or aft to balance the boat. If your seat is not in the exact spot then you are looking at adding ballast to trim the craft. If this is the first time you have built this design then you may want go with a larger opening.

Taking the issue to a ridiculous extreme: Contrast this with a very large "cockpit", like in an open canoe. a solo paddler can pick any spot along the length of the craft to place his seat, and should he catch a few fish, or dump 20 pounds of ice out of his cooler after he finishes his canned beverages, he can scoot fore or aft an inch or a yard to regain the trim.

Sprayskirts, particularly neoprene ones, stretch a bit, or some are designed to have some slack in them so the paddler can shift around a bit. You lose some of this functionality with a very tight cockpit opening.

If you want a small entry in order to avoid getting water into the boat, then there are other ways to achieve the same end, and have a larger entry. Boat with higher decks, or higher edges on the cockpit coamings, for example, keep out the water that splashes on the deck.

In any given boat lighter paddlers ride higher, heavier paddlers will find they are lower in the water. If you are a heavy paddler you may need a boat that has more displacement. If the design you chose gives you the added displacement through added length, then you may be stuck with a small cockpit opening. If you get the added displacement through added width, then you might consider a very wide cockpit opening, or a small one. Here you would have a choice.

Regardless of the size of the cockpit opening, if it is effectively sealed by a sprayskirt then you'll stay dry. If the sprayskirt seal is poor then the thing will work loose and you'll get wet. Think sponge or bilgepump. In the worst case, the design of the cockpit opening can act like a funnel and you'll have half the ocean inside the boat with you.

With a small cockpit opening you may not have a lot of room for an adjsutable back brace. If you are thinking of rolling, and want to lay flat on the rear deck, a small opening may make that difficult. YOu can put padding against the back of the cockpit for a back support. Remember that this will push your entire body forward a bit, though, so your center of gravity will go forward, too. Allow for the padding when you cut the hole.

If you are sitting all the way back in the cockpit, leaning on that closed-cell foam padding, then you lose the option of storing gear or lunch in the area behind your back support. This is a very convenient area to reach into -- if you have it.

Sitting lower in the boat will give you a lower center of gravity and that is usually a very good thing. It improves stability greatly.

Whatever size opening you cut -- be it large or small -- save the piece you remove. If your original opening is too large you can can then make it smaller by removing the coaming ring and making a smaller one. Cut a ring from the panel you've removed, and glass it into place. Yes, you'll have a ring showing the kerf from your first cut, but that can be filled in with a thin piece of veneer, or wood putty. It will be decorative. Cut your new hole and install the smaller coaming ring.

My take on the matter is to err a bit larger and use a good sprayskirt, or if you go with a small opening, be prepared to rip out the first one and move it a bit, or enlarge it, if needed.

Hope this helps

PGJ

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Re: Just adding a thought or two
Joe -- 1/23/2002, 7:31 pm
How close to rear of coaming can seat be
Joe -- 1/23/2002, 9:11 pm
Re: How close to rear of coaming can seat be
Jon Murray -- 1/24/2002, 12:26 pm
Re: How close to rear of coaming can seat be
Paul G. Jacobson -- 1/24/2002, 1:08 am
That Helps. Can Xact be determined B4 PDLN?
Joe -- 1/24/2002, 1:45 am