The purpose of this project is to design and mass-produce kits for a floating tiny house that can sail. It combines high-tech modeling and fabrication and low-tech assembly that can be carried out DIY-style on a riverbank or a beach. This boat is a 3-bedroom with a kitchen, a sauna and a dining room. The deck is big enough to throw dance parties. It can be used as a river boat, a canal boat or even a beach house. Oh, and it's rugged and stable enough to take out on the ocean. Kits will start at around $50k (USD). The design has been tested in simulation and prototype; full-scale production will begin next year.

Thursday, January 15, 2015

Fresh water and anchoring

Water tanks; chain locker
Water is what makes life possible, and salt water doesn't work too well for humans. Drinking it is a very bad idea, limited amounts of it can be used in making soup, it's useless for doing laundry because salted clothes never really dry, and although some salty dogs do wash in salt water, most people prefer fresh.

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.

26 comments:

  1. So, the locker is in front of the outboard well, correct? Is this like the outboard well, or does the well have a channel for just the chain to come up?

    The chains across the deck - will there be channels with movable cover, so you don't step on them/they don't catch anything, or is this just something to deal with? That's the only issue I could see. Most sailboats, yeah, have the locker in the bow, so that is moot.

    ReplyDelete
  2. The locker is only 2-3 feet high off the bottom, with a pipe leading up to the pilot house. I haven't yet thought through the arrangement for routing the chain from the bow to the helm. At a minimum, there needs to be a fairlead or two, and ideally there would be a plastic channel to keep the chain from scuffing up the deck.

    ReplyDelete
  3. If someone drops something down the pipe, do you have access to the locker in some other way? Does the locker drain someplace, or do you think it will be relatively dry?

    ReplyDelete
    Replies
    1. Yes. The chain locker will be accessible from one of the aft cabins, through a small hinged table.

      Delete
  4. It should be trivial to run a tubing drain line to the engine well.

    ReplyDelete
    Replies
    1. Actually the engine well is uphill from the chain locker. the drain will simply be a couple of holes cast into the concrete box that the chain will sit in, together with the bottom, that will drain toward the bilge pump. But the bilge pump will probably empty into the engine well, since that's the easiest thing to do.

      Delete
  5. Dmitry:

    Let me begin by saying I love the Quidnon blog. I don’t know the first thing about sailing but I’m a longtime ClubOrlov reader and have always enjoyed the sailing aspect of your writings. Like a previous commenter noted, I hope one day we’ll get an Orlov book on seasteading along the lines of Sailing the Farm or an expansion of your New Age of Sail. A recipe for sea squirrel pie perhaps?

    Since today’s post is about water tanks, I wanted to ask about re-provisioning at sea. You mentioned previously that Hogfish was rigged to collect rainwater, and had an on-board filtration system. Is this going to be a feature of the Quidnon project? Or perhaps some other method such as evaporation of salt water? From what I’ve seen most sailboats carry only 200 gallons or so, so perhaps 1300 gallons will make this less of a concern? I may be jumping the gun with my question but I haven’t seen any mention of this so far.

    Best of luck!

    ReplyDelete
    Replies
    1. Thanks, Ronald!

      Yes, there will be a rainwater collection system—and quite an extensive one. It would produce about a hundred gallons of water for every inch of rain. I will cover it in a future post.

      Delete
  6. 17 gallons per shower? ouch. We have a 3gpm fresh water pump, but the shower head is restricted to 1gpm.. just enough to shower with... and showers are always 10 minutes or less. . I would LOVE to have that amount for water. I calculate that based on the number of showers taken on our boat (currently spouse demands a daily shower), dishes done, water drank, hands washed, we could go about 10-12 weeks on your anticipated capacity. lovely....

    ReplyDelete
    Replies
    1. And that's not even considering the ability to collect rainwater during a storm! With a community of liveaboards all living on a mooring or at anchor, it's not beyond reasoning that Dmitri could sell his extra water to friends because it would save them a trip to the marina as well. I imagine that the task of procuring and maintaining a supply of freshwater is one of the most time consuming activities of living off grid, on a boat or otherwise. All that is required is an engine driven pump of quality, and the general knowledge among the community that Dmitri has some big tanks. Eventually, someone will make an offer for his surplus.

      Delete
    2. I for one am very interested in reading about such a "community of liveaboards". How might it function now, and what provisions for possible violent collapse of states / global financial system would be taken? I feel like there's this whole community of seasteaders "out there" and I am sitting on the shore with binoculars trying in vain to see how it all works.
      How do you go about finding suitable land to raise vegetables and fruit? Do you run on an annual migratory path etc? Fascinating.

      Delete
    3. I can recommend my friend Capt. Ray. His blog is http://www.theseagypsyphilosopher.blogspot.com/ and he is pretty far ahead of everyone of thinking out this very scenario.

      Delete
    4. I have read much from the Sea Gypsy in the past, and while he certainly has many valuable contributions to make; in my humble opinion he has an overly romantic view of pre-agricultural (or post-industrial) tribal societies. The idea that such societies didn't have such modern ills as slavery or cancer is easily disprovable. That said, the man certainly knows how to live on the sea without the support of modern civilizations' resources; so if it all does come crashing down, finding and making friends with Captain Ray is on my short list of priorities.

      Delete
  7. I noticed that your water tanks are forward of midline. Are the fuel tanks going to match aft? Or did you have some other plan for balance? Or would it not really matter with this much displacement?

    ReplyDelete
    Replies
    1. Yes, the fuel tanks, the chain locker and the propane locker and the engine are all going to be aft, and will balance out the water tanks somewhat, but mostly the balance will be adjusted by adjusting the thickness of the bottom concrete slab. It will probably average 3-4 inches, but will increase to 5-6 around the midline (where the boat will settle when drying out) and also aft of the midline. That is going to be a rather intricate calculation.

      Delete
  8. And with this much water storage, you might want to consider a WaterStep type DC clorinator, to keep the inside of the water bladders free of growth.

    ReplyDelete
    Replies
    1. There shouldn't be much growth in the bladders because there will be no air in them, and therefore no aeration and no oxygen. I'll make sure to use black pipes, so that no light gets in either, because that causes algae, which then die and stink. Half a cup of Clorox once a year is what I usually do to keep fresh water tanks fresh.

      Delete
    2. While half a cup per year might be enough assuming we can still buy bleach in bottles, a bottle of bleach doesn't keep longer than about two years. And if you're planning on collecting rainwater, there WILL be plenty of oxygen in your tanks following any good rain. Also, use copper pipes, or place a real silver coin into each of your bladders; the slow corrosion of either of these metals introduces free ions into the water, and is very effective against a wide swath of waterborne pathogens (but not algae, which just makes the water stink and taste bad). Copper pipes are the ONLY reason that Legionnaires' disease is so uncommon in the United States, since it has been shown to survive for more than 24 hours inside a new bottle of bleach. However, don't use both metals at the same time.

      Delete
  9. Dmitry, I recall you once saying that the attraction of squareboats included the ability for a couple of adults to drag it up onto a beach and back into the water. With all this talk of ballast, how would you ever move QUIDNON manually? It sounds like it would need 20 men.

    ReplyDelete
    Replies
    1. Actually the anchor winch will help get it up on shore, albeit slowly. The water tanks would need to be emptied first, of course, to lighten the load.

      Delete
  10. First thoughts is to have a central run for the chain from bow to locker. Off-center obviously but since there is not much tension on that part of the run you can even have curves in it. As it exits the run at the bow you have the winch and a single robust fairlead, then deck skid surface to the chocks. You can have the winch controls at the chain locker so you can draw the chain in and worm it in figure eights so it will pay out easily.

    The chain run could be surface mount with a large radius cover so as not to be a toe stubber, or have it run under the deck between the deck and cabin roof insulation. Line the bottom with HDPE (HDPE is easily welded) and you could even separate it into two tracks if you want. Also HDPE is readily available in tube. Build it so it is serviceable obviously.

    I know you are trying to keep the decks clean but this would only be up on the foredeck and would make the winch way more useful. I would also recommend a third anchor chock and roller in the very center as I believe this is the one you will use most in transit.

    Just tossing it out there in the spirit of the project.

    ReplyDelete
    Replies
    1. I thought of running the chain under the deck, but I really hate making any extra holes. A channel, open at the top, made of HDPE and running down the centerline of the deck right next to the masts is probably the easiest and tidiest approach.

      Delete
  11. Sorry if I go overboard (pun intended) with my input but I live for this stuff. Its such a wonderful break from my collapse/doom obsession.

    The chain run can also house the electrical and control cable if you go electric. If not then I definitely recommend mounting the winch at the bow if it is manual as it will be much stronger there.

    When single handing you can just let the chain pile up on a section of outdoor carpet as it comes off the winch then pull it back to the locker later.

    I would use a beefy double bollard as your fairlead in front of the winch. There is nothing like a solid bollard on the bow. I actually have one in my junk pile, also I made some before too.

    Man I wish you were doing this project out here I would love to help out.

    ReplyDelete
    Replies
    1. Having the winch at the bow causes the single-hander's problem of running back and forth between bow and helm to avoid hitting other boats in a crowded anchorage. Plus I have this interesting idea of making it possible to do everything and anything without setting foot outside of the pilot house.

      Delete
  12. Something occurred to me that might be a problem. You may have already considered this, Dmitri, and I don't know much about fiber in concrete; but I know that normal concrete can't take tension well at all, and pressure compounds. So with a rectangular box several feet long to the long side pressurized to 20 psi is going to be holding several thousand pounds of static tension on each inner face. I've personally seen concrete fail due to a 4 psi static pressure against a flat face, so I'd recommend you check your numbers with another engineer with experience with concrete pressure vessels. It would be unlikely to fail catastrophicly, but even a crack is going to ruin your day and maybe swamp your cabin.

    ReplyDelete
  13. Thank you for worrying. I worry too. I have looked at concrete barge construction that complies with California building codes. The design strength is 4000 psi. They use #4 rebars, fusion coated, on 12" centers. There are some special requirements with supporting the mast steps. I am considering using I-beams to spread the load across the bottom and tie in with frames and deck beams. I am going to call up the California houseboat people, and see if I can get them to do a bit of consulting on this project. Leaks from cracking are unlikely because I am going to sheathe the bottom in fiberglass. So it will really be a fiberglass hull with concrete used to spread the load. I am still worried about the joint between the plywood/fiberglass topsides and deck and the concrete/fiberglass bottom. But I think that if I overdesign the hell out of it, it will last 80 years like the design life of the concrete houseboats I am reading about.

    ReplyDelete