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Water tanks; chain locker |
Most sailboats are quite limited in the amount of fresh water they carry, and when they are used as houseboats outside of a marina (where they can be hooked up directly to shore water) this translates into some amount of discomfort for the residents. When living at a mooring or at anchor (the most economical way to live aboard) it is reasonable to pull up to a fuel dock once a month to pick up water; more often than that, and it becomes a repetitive chore.
QUIDNON has plentiful room for tankage in the awkward, otherwise useless space between the centerboard trunks and the hull. It adds up to 184 cubic feet of space, which equates to 1380 gallons (5225 liters) of tankage and 11,600 lbs of water ballast. A typical shower uses 17 gallons of water, and this means that QUIDNON's water tanks will be sufficient to provide 80 showers.
To be useful as ballast, the water tanks have to be kept full. This, it turns out, is quite easy to arrange by using fresh water bladders made of weldable nylon floating inside tanks that are kept full of salt water, and at “boat pressure” (20 psi or so, much lower than house pressure) using a demand pump. The demand pump is turned off when filling a tank, and the bladders are sized to be somewhat larger than the tanks in which they sit, so that they are never under any pressure. This will make the bladders last a very long time, but spares would of course be carried, so that a new bladder can be swapped in if a tank starts to taste brackish. The tube that taps into a bladder will come out the top, to bleed off the gas that results when the tanks are filled with chlorinated water.
A secondary, fresh water pump would need to be provided for when the boat is drying out during low tide and salt water is temporarily unavailable. The switch-over between the two pumps can happen automatically using a float switch. This will help eliminate the spectacle of annoyed naked people covered in suds running from the shower to the switch panel and back when the tide goes out (and, of course, forgetting to flip the switches back when the tide comes back in and then wondering why the boat is listing to one side).
In addition to the water tanks, another source of “free” ballast comes in the form of anchor chain. A boat of QUIDNON's size requires 7/16-inch chain, about 300 feet of it, which weighs 675 lbs. Well, it's not exactly free; the cost is $2,250 last I checked; but it is otherwise necessary. Nylon rode is quite a lot cheaper, but far less reliable, and for a houseboat that spends most of its time anchored all-chain anchor rode is recommended.
Many sailboat designers find it fun to put a quarter of a ton of chain right at the bow of the boat—the part that's supposed to be especially buoyant. And then they wonder why their designs pitchpole, broach and snap off their masts. By doing so, they create a number of problems. First, obviously, is the weight issue all the way forward: adding weight there increases the angular moment of the boat, causing it to build up angular momentum when bounding up and down waves. Secondly, it is rather difficult for a single-handler to both steer the boat and work the anchor winch in a crowded anchorage, running back and forth between the bow and the helm. Third, while this arrangement makes it possible (if not easy for a single-handler) to anchor from the bow, it makes it almost impossible to anchor from the stern, which is what you want to do when you are heading toward a beach and want to leave open the possibility of getting off that beach again unassisted. This is known as “throwing out a kedge”: the anchor is let go from the transom. Question is, how do you winch in the kedge if the anchor winch is all the way at the bow?
And so, on QUIDNON, what I want to do is locate the chain locker closer to the stern than the bow, so that the anchor winch can be placed right next to all the other lines and controls. There will be two anchor rollers at the bow, tipped down so that the anchors will fall as soon as the anchor chain is given some slack. The anchor chain will drag clear across the deck, through a secondary roller in an aperture at the front of the pilot house, and down into the chain locker below. The reason the anchor rollers are spaced far apart is that QUIDNON will ride much more quietly to anchor when anchored at an angle, so that it presents a V to the waves, cutting through them, instead of slapping into each one with its blunt bow. Anchoring at an angle will also cut down on the noise and put less wear on the mainsail if it is used as a riding sail while at anchor, because then, sheeted in tight, it will always be drawing to one side instead of slatting back and forth.
What all of this adds up to is 15,000 lbs of “free” (or, rather, multipurpose) ballast, enough fresh water for 100 showers, and easy anchoring off the bow or the stern for the single-hander.
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