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 four-bedroom with a kitchen, a bathroom/sauna, a dining room and a living 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. It's rugged and stable enough to take out on the ocean.

Thursday, January 22, 2015

Deck and pilot house


Most sailboats have low topsides, making them look sleek and sexy. But then the deck ends up too low to walk under down below without having to stoop. To compensate, most of them have a silly little structure called a cabin-top, which is basically an elongated box to accommodate your head while you make your way through the cabin. Many designers streamline the shape of the cabin-top. This adds nothing to the aerodynamics of the hull, while making it more likely that somebody will slip and fall while stumbling around on a wet and slippery deck. The narrow little passageways on both sides of the cabin-top, called the side-decks, are often too narrow for two people to get past each other.

On QUIDNON the topsides are high enough to provide 6 feet of headroom down below, and to keep most of the salt spray off the deck when sailing. There is no cabin-top because the deck is a flush deck—from one side of the boat all the way to the other. It is flat, not “whale-backed,” so that people can stroll about the deck with a comfortably horizontal surface under their feet. And I want to make every effort to keep it relatively uncluttered, so that it can serve as many different functions as there are situations in life.

But that, it turns out, is quite a challenge. The unavoidable obstructions are the following.

1. Two anchor rollers at the bow, with shallow channels made of SeaBoard (HDPE plastic) leading the chain past two additional vertical-axis rollers which deflect the chain from each bow roller to the anchor winch in the cockpit. The bow rollers are angled down, so that to let go the anchor it is sufficient to release the chain. This arrangement allows a single-hander to steer the boat while simultaneously laying out or hauling in the anchor, making single-handed anchoring in crowded anchorages less of an adventure and less of a menace to society. The reason the anchor rollers are offset to the sides is that, given its blunt bow, QUIDNON would make continuous slapping noises if anchored directly from the bow, whereas if anchored from the offset rollers it will cut through the waves with one of its hard chines and ride quietly.

2. All the lines to control the sails and the centerboards go to the pilot house. All but one of them go through three sets of sheaves; the foresail sheet requires one more so as not to interfere with the pilot house door. For each mast, these include:

• Halyard, with a 4-part purchase between the masthead and the shackle that attaches to the yard.
• Sheet, which goes to the sheet block. For the foresail, the sheet block is located on the boom gallows; for the mainsail, it is mounted on the roof of the pilot house.
• Aft topping lift, which is used to lift the sails off the boom gallows or the pilot house roof when raising them. Since the entire sail bundle, with the boom, the yard, 5 battens, 500 square feet of canvas, parrels and other bits and pieces weighs a lot, the topping lift is hauled up using a 4-part purchase near the masthead, same as the one used for the halyard.
• Two sets of reefing lines, each of which is attached to a block hanging off two neighboring battens, so that 4 different reefs are possible, with the deepest reef leaving up just the triangular "storm sail."
• A yard hauling parrel, which is used to pull the yard to the mast.

For each sail, two lines are not led back to the cockpit, because they hardly ever need adjusting once the sail has been rigged. These are:

• Boom downhaul, which keeps the sail from riding up the mast. It goes from the boom to a padeye on deck just aft of the mast.
• Forward topping lift, which holds up the front end of the boom when the sail is down, and is slack when the sail is up. It goes from the masthead, through a padeye in the front of the boom, back up to the masthead, through a sheave, and back down to a cleat bolted to the tabernacle.

3. Two centerboard purchases. These are 3-part purchases that slide along the deck. When tensioned, the blocks hang just above the deck, so that if a centerboard hits an underwater obstacle, the clatter of the block against the deck serves as a depth sounder of last resort. The line that goes from the centerboard to the sliding block is under quite a bit of tension, and the best material to use for it is Spectra braid of similar. To give the sliding block enough room to slide, the line from the tip of each centerboard is led up through the aft end of the centerboard trunk, over a sheave, forward to the front of the centerboard trunk, up to the deck through a 3" PVC pipe, and over another sheave. The pipe doubles as a deck drain: water is allowed to drain freely from the deck through the pipe and into the centerboard trunk.

4. Three deck beams made of 4x6 fir (or larch?) sticks, lightly fiberglassed and painted to preserve them. I initially thought of putting them below deck, but then realized that they are needed above deck for a number of reasons, plus people would curse me for this decision every time they knock their heads against it while walking through the cabin. The upper edges of the deck beams are rounded off, while their lower edges have slots in them to send through the chains and the lines. Their functions are:

• Along with the gunwales, which they abut, support the stanchion bases for the lifelines, which I will discuss in a future post.
• Reinforce the deck, especially at the masts, where the blocks through which the mast tabernacles emerge are bolted to them.
• Reinforce the deck around the deck hatch. The beams run just forward and just aft of the hole in the deck, making up for the weakness it introduces. The dam that surrounds the hatch opening works together with the deck beams, acting as a longitudinal stiffener.
• Support dinghies when they are carried on deck, bottom up, without interfering with any of the lines, and provide a way to lash the dinghies down.
• When breaking waves inundate the deck, steer them away from the pilot house and toward the scuppers.
• When all hell breaks loose and sails come tumbling down from the mast in a heap, provide lots of places to lash them down quickly.

The pilot house

The pilot house serves the following purposes:

• Keep the crew out of the elements. (As I mentioned, my goal is to make a sailboat that can cross an ocean without making the helmsman change out of his bathrobe and bunny slippers, or put down his mug of hot cocoa.) I am designing QUIDNON so that it can be sailed without a deck crew.
• Provide additional buoyancy when the boat is knocked down on its beam ends. The doors of the pilot house are close to the center-line, mounted on the outside, and the sides of the pilot house are completely watertight, so that when the boat is knocked down on its beam ends and one side of the pilot house is submerged, it remains watertight, provides additional buoyancy, makes the boat harder to capsize and increases the righting moment of the hull.
• Keep water from inundating the cabin, be it rain, spindrift, breaking waves crashing on deck or solid sea water in the event of a knockdown or a capsize.
• Provide the helmsman with a panoramic view of the surroundings and a good view of the sails.
• Provide access to the transom for handling the stern line and the aft spring line when docking.
• Provide more living space during the warm months of the year
• Provide storage space during the cold months of the year, serving as a “mud room.”
• Serve as a greenhouse for potted plants.
• Provide a large surface for rainwater collection.
• Provide a mounting surface for solar panels.
• Provide a mounting place for mainsail sheet blocks.
• Serve as boom gallows for the mainsail.

At the center of the pilot house is the helm. It shows a wheel, although my general preference is for a tiller. This is because I hardly ever steer by hand, letting the autopilot attend to the course-keeping, but when I do hand-steer it's because I want quick, precise results: I am tacking or gybing or maneuvering in close quarters. About the only time a wheel is really useful is when motoring down canals. But most people prefer a wheel.

I haven't yet figured out a way to combine wheel steering with the use of a tillerpilot (Simrad TP32 is the most cost-effective and reliable autopilot solution I have found so far for both steering a compass course and sailing to wind.) Nor do I know exactly how the steering linkages are going to be laid out. These are subjects for a future post.

The wheel is mounted on the instrument pedestal, which will carry a compass, an integrated GPS chartplotter/sonar/radar display, a VHF radio and the engine controls (starter button, kill switch, shift lever and throttle). The helmsman's seat is an armchair that pivots left and right for hauling on lines, slides forward when it's time to hand-steer, and slides back again when the autopilot takes over, so that the helmsman can use the wheel as a footrest, lean back and read a book. Directly above the helmsman's seat is a skylight, affording a full view of the sails, so that the sheets can be trimmed accurately without having to do any rubbernecking. Most of the sailing will be done by pushing buttons on the autohelm's remote control and by making small adjustments to the sheets.

To the right and the left of the helmsman's seat are boxes of line. The junk rig does not require the use of winches because it uses purchases everywhere they are necessary, but this results in a really huge amount of line, which, if allowed to pile up randomly, creates a rat's nest of kinks and tangles, which can be dangerous. The row of boxes to starboard is for the mainsail; the one to port is for the foresail. There are also boxes for the centerboard purchases, each on its corresponding side. There are dedicated boxes for sheets, halyards, and centerboard purchases, and a common box for topping lifts, reefing lines and yard hauling parrels, which don't generate as big a mess. Each box is equipped with a sheave to send the line up to the box, a fairlead to let it enter the box and either a jam cleat (for sheets, which are trimmed frequently, and centerboard control lines) or horn cleats (for all the other lines, which are handled infrequently but need to be made fast very reliably. Because of the use of purchases, the line can be relatively thin and inexpensive: 1/4-inch nylon for sheets; 3/8 Dacron for centerboards and halyards, which need to be low-stretch; 3/8 polypropylene for the rest.

Just to starboard of the instrument pedestal is the anchor winch, with the chain locker directly below and the anchor chain fed down to it through a pipe. My preference is for a manual three-speed winch because electric winches kill batteries in a big hurry. Electric winches introduce unnecessary expense and complexity.

Forward of the instrument pedestal is the companionway. It is surrounded by a 1-foot-high dam (higher toward the front), which is meant to prevent water from pouring into the cabin if a wave should succeed in entering the pilot house. The companionway hatch is 2 feet wide, and has doors that resemble bulkhead doors which flop open to the left and right and hang down alongside the dam. A chin-up bar at the front of the companionway hatch makes it possible to swing down into the cabin instead of using the ladder. The companionway doors serve the following needs:

• Prevent heat from escaping when the cabin is being heated
• Prevent light pollution from the cabin from interfering with the helmsman's night vision
• Provide a way of locking the cabin securely
• Keep water out of the cabin should the pilot house get swept away by a rogue wave or a force-5 hurricane

Along the sides of the pilot house are two large settees with lockers underneath. These can serve as additional berths when two too many guests show up, or as preferred places to sleep in hot weather, when the cabin remains sweltering all night, while the pilot house gets cooled off quickly by the evening breeze.

The pilot house has 4 doors. The two that are forward are hinged, while the two that are aft are sliding doors because there is no room aft for hinged doors to swing open. They overlap their openings by a generous amount, so that they are unlikely to yield when hit by a wave. The windows in the doors are made of overlapping ¼-inch Lexan backed by square aluminum pipe. The thresholds of the doors are 6 inches above deck, to provide another defense against water ingress.

One feature of the pilot house that may not seem entirely satisfactory is the lack of ample headroom: along the centerline, it is just 4'6", while along the sides it is just 4 feet. The idea is to provide sufficient headroom when seated, but not to provide standing room of any sort. Moving around the pilot house will be similar to moving around in a minibus or a small airplane. Of course, it is possible to build the pilot house taller, but this would incur some penalties: it would create more windage and hurt the boat's performance when sailing to windward, and it would either reduce the sail area or require taller masts, and call for more ballast. And so I feel it is best to leave the pilot house as a place to sit, and the deck as a place to go and stretch one's legs.

11 comments:

  1. It seems like standing while piloting would help comfort, leverage, and health. Like a standing desk.

    Have you considered lowering the cabin floor just in the middle controls area? Steal some head room from the berths?

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    1. Actually, I found the opposite to be the case. Piloting is mostly about pushing buttons; the wheel is generally left alone. And it's harder to push buttons standing up than sitting down. Likewise, pulling on lines is easier seated, especially if there is something to push against with one leg.

      I have considered stealing some space from the cabin down below, but that creates several problems. One is that the illumination that comes from the unbroken row of deadlights all around the cabin would be lost to the aft cabins, making them into dark holes. The other is that it would require either lowering the transom or creating a large bathtub out of the pilothouse floor that would capsize the boat if it filled with seawater. None of these choices please me. I may end up raising the pilothouse roof by another 6 inches or so, bringing it up to 5 feet.

      But the underside of the pilot house will be covered with a soft liner backed up with something soft, and people generally don't mind bumping their heads against something that feels like a pillow.

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  2. Would it complicate matters too much to have a hatch over the companion way extending either side over the parts of the floor just inside the doors? When Quidnon is not under way, opening this would allow people to enter the cabin without having to be bent over for several steps, which is pretty awkward if carrying anything heavy.

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    1. Well, I agree that it would be a nice enhancement. But it has nowhere to slide back, because it would hit the mainsl sheet blocks. It could slide sideways, but then it would interfere with the solar panels. It could fold down and up under the pilot house roof, but then it would further decrease the already low headroom, plus there is no way to make such an arrangement leak-proof. Also, any such arrangement would compromise the structural integrity of the pilot house as a source of reserve buoyancy in a knock-down and less able to stand up to a breaking wave.

      In general, carrying anything heavy (or almost anything at all) between pilot house and cabin will involve temporarily putting it down. That's how it ends up working with any design.

      I'll play with boosting the headroom by 6" to 5 feet and making the tabernacles and the boom gallows correspondingly higher. Also, having a lip around the companionway opening is a good idea, but after doing some calculations I decided that having a foot of water in the pilot house is so dire a situation for its effect on stability that if the water wants to go down into the cabin it should, because then the boat can stand up and let the bilge pump pump the water overboard. So I'll reduce the dam around the companionway opening down to 2-3" and provide a grille at the bottom of the companionway ladder to let water drain down into the bilge instead of sloshing around on the cabin sole.

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    2. Assuming that there is room under the boom, could the hatch pop up like the roof of a camper van? This would have the advantage of letting additonal light and air into the pilot house whilst being at least partially rainproof.

      I take your point about structural integrity. It reminded me of a lovely 20ft cutter, called Bina, once owned by my uncle, which had been designed and built out of wood by its first owner. It was remarkable how different it was from the mass-produced fibreglass yachts it was always surrounded by when in a marina. Reading about Quidnon, I find that the designer of Bina, who I also knew, had often thought along the same lines as you, e.g. the bowsprit was easily retractable.

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  3. Have you considered whipstaff steering for the pilot house as an alternative to a wheel? The geometry would fit better with an actual tiller (perhaps under the sole) and make for simpler connections.

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    1. Actually, that's what I have in mind, more or less. The twin rudder stocks will have short tillers through them above the level of the pilothouse deck. They will be joined to a tie-rod using ball joints. The tie-rod will have a horizontally pivoting slip bearing in the middle of it, and a vertical rod will go through it. The vertical rod will plug into a horizontal rod that will run at the pilot house floor level. The horizontal rod will rotate in two bearings, fore and aft. At the console, another rod will plug into it, and the top of that rod will have a rack that will be engaged by a pinion on the steering wheel (by shoving it forward on its axis) and a pin for clipping on the telescoping rod of the tiller pilot. So, if somebody doesn't like the wheel and just wants to steer using a whipstaff, it's a matter of unscrewing the wheel and the rack, and adding a handle to the whipstaff that's already there.

      Basically, I want to make it possible to steer no matter what happens. So if one of the rudders hits something underwater and becomes inoperative, it can be removed and hauled aboard by pulling out one pin and undoing one nut, and then the voyage can continue with the other rudder.

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  4. Don't know your specifics but I would have the two rudder posts linked directly across the boat via some bomber struts or cables. Then on the centerline have a quadrant on the strut or cable and a secondary rudder post come up through the deck into the pilot house or near, possibly under the seat. This in turn has a quadrant with cabling running to the wheel but also can accommodate an emergency tiller that keys onto the top of the post incase the wheel goes out.

    I would also recommend having attachment points on the rudders so you can easily attach line and rig alternative steering method in case the whole thing goes out.

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    1. See previous comment. That ought to be about as bombproof as anything I can think of.

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  5. Dmitry, I have a composting loo on my liveaboard. Also do liquid and solid separation, pretty completely (not always possible, of course, especially not at my age...) I think you're going to need more than a five-gallon bucket, aren't you, to have the composting one ready to empty, before the active one is full? BTW, I throw in one small scoop of sawdust, forest-floor soil, or similar soak-up/cover-up material to the bucket each time. That works well, and reduces objectionableness almost to zero, within minutes. Doesn't need to be dry; works just as well either way.

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    1. Well, the 2-bucket solution may not create real compost, but at least it reduces the moisture content, so that by the time a bucket needs to be dumped it's easier to carry to the marina dumpster. Ground coconut husks make the best absorber, but peat moss works too, as does sawdust and leaf litter, provided it's dry.

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