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.

Friday, October 9, 2015

Cockpit design: a picture plus a few thousand words

As I mentioned before, nothing focuses the mind on cockpit design like spending 150 hours in the cockpit of a sailboat more or less in one continuous stretch. Previously, I outlined my conclusions from this experience in prose, but this time I have an actual 3D rendering of my proposed design, with all the details filled in.

And nothing focuses the mind on the need to finish designing and build a houseboat that sails more than what is currently unfolding in South Carolina, which I just recently sailed through. Last week, Charleston, where I had spent a week, had fairly deep water running over the streets. Next week it will be Georgetown's turn; the entire town, where I had spent a few days too, is going to have to be evacuated. “You are lucky to be on a boat!” people keep telling me. Indeed, I am! But it's not exactly the right boat; it's a pretty good boat, but it's not QUIDNON.

What's been happening in South Carolina is but a preview of coming attractions. People are still calling it “a thousand-year flood,” not realizing that the next 10 years will bear little resemblance to the last 1000. Interesting things happen to the normal curve when you move the mean: what used to be uncommon can become commonplace rather suddenly. This is exactly what rapid global warming is doing: moving the mean. We are already most of the way a to 2ºC temperature rise, and heading toward 6ºC. It is about time we all got used to it.

We already pretty much know that the entire Eastern Seaboard of the US, where half of its population lives and where most of the infrastructure is, is going to be underwater and uninhabitable roughly by mid-century. Well before then access to potable water, the electric grid, piped natural gas, passable roads and structurally sound bridges and other trappings of civilization will become problematic for a growing percentage of population. This is because the money needed to rebuild the infrastructure after each cataclysm will not exist.

A lot of these people will wish that they were living on a QUIDNON, with its big water tanks, propane lockers, its own electricity, a bulletproof copper-clad bottom and, most importantly, the ability to float and to move about using the wind and the currents. And this thought has given me the impetus to finish the design. Here is the picture, which I hope is worth a thousand words, and worth even more with a few thousand words added.


QUIDNON has a flush deck. There is no cabintop—just a vast expanse of flat deck, 36 feet long and, at its widest, 16 feet wide, with gunwales and lifelines all around. The superstructure consists of two masts, two arches (which serve many purposes) and the cockpit. The cockpit, located just aft of the mainmast, encloses the companionway and the cockpit well. The cockpit well's floor is made up of hardwood slats with gaps between them, and drains into the anchor chain locker below it. In turn, the chain locker drains into the inboard/outboard engine well immediately aft of it. Space for the anchor chain locker and the engine well is carved out of cabin space using three full bulkheads: on one side of the bulkheads is “boat”; on the other is “sea.” Even if a huge sea breaks on deck and floods the cockpit, it will harmlessly gurgle away through the cockpit floor in a matter of seconds.

The Dodger

The dodger is a box made of polycarbonate plastic and fiberglass-reinforced plywood. Except for its top, which is slightly curved, to add rigidity and to make it shed water better, it is a box. Most dodger designs have a windshield that slants back, but this is very bad for visibility, especially when it's raining. Most working boats have windshields that slant forward; this provides maximum visibility, but looks downright ugly on a sailboat. The compromise is to make it perfectly plumb and square. Another common concession to style is to curve the windshield, but this detracts from windward performance. When going to windward, at a 35-40º angle to the wind, it is better to present a sharp corner to the wind then a flat surface. And so the dodger is just a box: simple, sturdy, and cheap to build. I made such a dodger for my current boat before I left Boston and have verified that it works quite well. The polycarbonate of the windshield and the side windows is structural; joined at the corners using aluminum angles, it is very stiff and able to deflect a big wave and any kind of wind. Below the top of the dodger is a box, which can be locked using a lid that nestles in a slot above it, and which holds the VHF radio, the chartplotter and an old-fashioned magnetic compass (still very useful for when all else fails).

The Lazarettes

There are upper and lower seating positions provided for by two lazarettes that run fore-and-aft. The lazarettes serve as backrests for the lower seating positions, and as seats for the upper ones. All seating positions have backrests which are angled out for comfort. The seats are surfaced with nonskid because they perform double duty as places to stand. The lazarettes provide locker space for things that are generally stored in the cockpit. The two lockers inside the dodger, with top-opening hatches, can be used to store paper charts, the logbook and navigation guides; flashlights, a flare gun and flares, emergency satellite transmitter, rigging tools, snacks and drinks and so on. The four lockers further aft have hatches that tip out, and can hold foul weather gear, dock lines, fenders and other such items, none of which belong in the cabin.

The Companionway

The companionway hatch lid hides in a slot just aft of the companionway. To close the hatch, it pulls out of the slot and flops forward over the companionway. The hatch lid holds a bug screen inside it, which can be pulled out and used separately. This, it turns out, is a very big deal at certain times. When sailing past an agricultural area with an offshore wind, flies that get blown off the land head straight for any sail they can spot. Then they get hungry, and very bitey. For those in the cockpit, swatting as many of them as quickly as possible is a good idea, because then they eat their own dead, preferring cannibalism to human flesh. For those in the cabin, the idea is to keep them out of the cabin.

The Tiller

As I explained previously, I have determined that wheel steering is a bad idea, and that a tiller is the way to go. But what sort of tiller? Having had quite a lot of experience with tillers, I designed one that I think will be particularly versatile. It is an aluminum pipe—strong and lightweight—that is precisely horizontal. It positioned so that were it to swing violently (as tillers are sometimes wont to do in sloppy conditions) it wouldn't cause too much damage.

For someone seated in the lower seating position, where the seat is at deck level and one's back is against a lazarette, it should hit that someone right below the belly button. Anywhere lower—and it may hit a kneecap; anywhere higher—and it may hit the solar plexus. If it hits even higher, it may hit the funny bone or crack a rib. None of this is helpful for one's continued ability to steer a boat. And so right below the belly button is where you want to hit an inattentive helmsman—if you have to. The gut is fairly immune to blunt trauma, being well protected by a layer of muscle (for those who do sit-ups) and a layer of fat (for those who also regularly exercise with 16-ounce weights). For the upper seating position, the tiller should hit the shin, or the sea boot if one is wearing them. This is painful, but the shin bone is strong and can take it, and the pain is rarely bad enough to force you to neglect your course-keeping duties.

Inside the tiller tube lives the tiller extension. It is made up of two more tubes, which slide inside one another and can be locked together at an arbitrary length by twisting them against each other. At the outer end is a comfortable handle. At the inner end is a hinge; when pulled out of the tiller as far as it will go, the tiller extension can be operated from any angle: seated on a lazarette, or even standing at the lifelines and looking over the side—this being very useful while docking. When pulled out only part of the way, the tiller extension can't pivot and just makes the tiller longer and increases its lever arm. This also makes it possible to steer while sheltering under the dodger as you would during a torrential downpour.

This tiller design allows for a lot of comfortable and useful steering positions: seated facing forward with one arm draped over the tiller; in the lower sitting position facing sideways, with one foot on the tiller; in the upper sitting position, with the tiller extension tucked under the armpit; standing on a lazarette and peering over the top of the dodger (as you have to in fog, when the dodger becomes opaque because it becomes coated with tiny droplets of water); leaning over the lifelines while steering toward the approaching dock; and so on.

There is one more steering position that I would be remiss not to mention: with the tiller swinging between the legs, or tapping against a thigh. When dropping anchor, or weighing anchor, or doing anything at all with the sails, it is very useful to be able to free both hands for the operation, while continuing to steer the boat, and being able to steer with your legs is what makes it possible. I once asked Chris Morejohn what his trick was for tacking the huge genoa on his Hogfish all by himself, and his laconic response was: “A sheet in each hand and the tiller up the ass.” (I am sure that he was speaking figuratively, and that we both reserve our anal sphincters for purely sanitary uses.) Here too the vertical position of the tiller is important: it should rest against the thigh; any higher, and one's continued ability to beget progeny may come into question.

Lastly, there must be a way to fix the tiller at any given angle. This is provided for using a tiller rack, which is a toothed rack mounted directly below the tiller at the back of the cockpit. The tiller has very restricted vertical travel—less than an inch—and is equipped with a spring-loaded detent that allows it to be either all the way up or all the way down. When forced into the lower position, it engages the toothed rack and cannot be moved sideways. This is an essential feature. The rudder is fixed at an angle when heaving to. It is fixed amidships when engaging the autopilot (which takes over the steering at a point between the tiller and the rudders). And it is clamped down at some appropriate angle when temporarily abandoning the steering because there is something more important for you to attend to.

Anchoring

QUIDNON's two anchor rollers are located on two sides of the bow, some feet apart, because with QUIDNON's hull shape anchoring at an angle to wind and waves, splitting them along the hard chine instead of taking them head-on with the bluff bow, produces much more pleasant motion and far less noise.

The anchor chain locker is located underneath the cockpit, with the anchor chains running in a channel and around rollers along the deck. The two chains converge at the cockpit, where, on the starboard side, is a manual anchor winch. The chains then disappear down holes just aft of the anchor winch, and are pulled down into the chain locker by gravity.

Two short snubbers (not shown) can be used to hook the chains right in the cockpit. Of course, a real snubber, fitted right at the bow, is always an excellent idea, and the anchors should always be secured at the bow while underway. But all other anchoring operations can be performed right from the cockpit, while steering and using the engine—a single-handers dream!

Engine

The engine is an outboard that is mounted inboard, in a well right behind the cockpit. Instead of tipping up when not in use it slides up on a track. The engine is pulled out of the water using a hoist, the line from which is found among the running rigging.

The hatch over the engine well is slightly recessed and made up of hardwood slats with gaps between them, just like the floor of the cockpit well, so that any seas that wander aboard from the stern find an easy way back down instead of inundating the cockpit and drenching its inhabitants. Inside the engine well, right below the hatch, is a baffle that deflects the flow of water away from the engine while also providing sound insulation.

The engine control box is mounted on the starboard lazarette, just inside the dodger, and includes an integrated shift/throttle lever, a starter button, a kill switch, a fuel pump switch (since there is no convenient way to access a squeeze bulb) and, for the engines that need it, a choke lever.

Running rigging

All of the running rigging enters the cockpit through the front of the dodger and goes through a block of rope clutches. It's all 3/8" 3-strand polypropylene line, and there is a lot of it, because everything is done using blocks instead of winches, the only winch being the anchor winch. The halyards alone are 200 feet apiece. A 600-foot spool of 3/8 3-strand polypropylene, of the sort fishermen use, is around $50; fancy Regatta Braid will run you almost 10 times that.

Since the line is purchased in bulk, it isn't color-coded, so that the only way to identify a line is by looking at the cluck block, which is labeled as follows:

port centerboard hoist
stbd centerboard hoist

engine hoist

fore halyard
aft halyard

fore topping lift
aft topping lift

fore reefing line
aft reefing line

fore sheet
aft sheet

The lines are paired up—fore/aft and port/starboard—because you might actually use them together, raising, reefing and lowering the two sails in tandem, dropping and raising both centerboards at once, and trimming the sheets on both sails together. Hoisting both sails together would take quite a bit of muscle: all hands on deck, and an appropriate chanty to be sung while heaving them up.

After they exit the clutch, the lines disappear into a slot which leads them to a set of take-up reels mounted in a cage at the top of the anchor chain locker, right below the floor of the cockpit well. These are spools, like the ones that rope or heavy-gauge wire comes on when purchased in bulk. Inside the hub of each spool is a loop of neoprene strapping arranged to create a “rubber band motor.” Each spool is spun up using a winch handle to tension the neoprene loop before the bitter end of the line is attached to it, then the spool is released and it spools up all of the slack. Once in a while the neoprene loop will snap and one of the dozen lines fails to disappear below deck; then it's time to lift out the cockpit well floor, grab a winch handle and a spare loop of neoprene, jump down onto the anchor chain and fix it. I believe that this is a small price to pay for not having to live in a rat's nest of line, and I am sure that once you experience this system, the usual ways of handling line will seem absolutely stone-age.

Handrails

There are handrails (bent and welded out of 1-inch thick-wall stainless steel tubing) that go all the way around the cockpit, so that no matter where you stand or sit there is always a handhold within easy reach. The rails along the sides of the lazarettes and the back of the cockpit double as backrests. The vertical rails on either side of the dodger are helpful when climbing in or out of the cockpit. The horizontal rail along the back of the dodger is used when climbing in or out of the companionway, or to steady yourself while using the instruments under the dodger. The rails that wrap around the front of the dodger help you catch yourself instead of going splat against the windshield when a big wave knocks you off your feet.

Dimensions

Because there is plenty of room on deck, this cockpit design can be scaled based on the height of the intended crew. The only dimensions that are fixed are those of the companionway and the cockpit well.

Minimum height is more important than maximum height; having to stoop a bit or feeling a bit cramped is never lethal, while not being able to reach something essential, or to steady yourself because the handholds are too high or too far apart, very well can be. Women tend to be shorter than men, and rather few women are over six feet tall. And yet I have seen plenty of cockpit layouts designed for someone at least six feet tall—probably a man, and probably a man who expected some poor woman who, chances are, is significantly shorter than he is, to go sailing with him—and to actually enjoy it! This goes double for children: if you expect them to enjoy sailing with feet dangling and nothing within reach to hold on to, then your expectations are a bit unrealistic.

And so it turns out that the best cockpit design must take these considerations into account, making it possible—though not necessarily comfortable—for everyone to do everything. The shortest crew member has to be able to peer over the top of the dodger on a foggy day; the tallest crew member has to be able to stretch out (almost) all the way when lying down in the cockpit. And so the design parameter I plan to plug in everywhere is 5 feet 6 inches, or 168 cm. Of course, it will still be possible to plug in a bigger number when building a QUIDNON that is to be operated by a race of giants, as I am sure it will be.

27 comments:

  1. Nice!

    I wish I knew more about sailing. I have a feeling I am going to regret not knowing more. :-(

    - KK

    ReplyDelete
    Replies
    1. I just read, courtesy of the Friends Of The Library 50c paperback policy, Herman melevilles s first book, Redburn, His First Journey. It's an excellent book! But I pith those who read it and don't know what a spanker boom is, or what the scuppers might be.

      Delete
  2. Counterweight or spring assist for the engine hoist? I assume you want to bring it up for servicing otherwise the hydraulic engine tilt would do? As always, enjoying your stuff!

    ReplyDelete
  3. Well, Karl, that's easy to fix. There is a million places to learn sailing, and the process is immensely enjoyable.

    Alan, the engine hoist is just a hoist, of the sort used to hoist outboard engines, with a 5-part purchase. The engine tilt wouldn't work the engine is in a well, and at the bottom there is only enough room to pass the cavitation plate.

    ReplyDelete
  4. A square hulled boat and consideration for smaller people - my estimation of you just rose up a notch!

    ReplyDelete
  5. Color me impressed!

    It's been all I can do to do finally come up with a good folding table drawing board design, simple as shit and folding is important because I, and most Americans, live in cramped spaces these days. You can't buy my design in stores though, which is weird, its so obvious.

    BTW as a side note, I love in the heart if the so called silicon valley, and the digital divide is growing fast. I have a shitty tablet for my work, which pays what I made just out of high school. A windows 3.11 machine from 20 years ago would run circles around it. My actual word transmission rate as I peck this out is on a par with 5wpm Morse code. I expect my internet access to only get worse, as time goes on.

    So, give us a mailing address so we can send you random cash donations and subscribe to the Dmitry Orlov mimeographed newsletter!

    ReplyDelete
  6. Well I do intend to distribute PAPER study plans once the design is finished. Luddites, rejoice!

    ReplyDelete
  7. This comment has been removed by the author.

    ReplyDelete
  8. Have you calculated the fresh air and exhaust requirements for operating the engine in the well under all conditions?

    ReplyDelete
  9. The fresh air will come in through the engine hatch, which has slots in it. When the engine is in idle, the exhaust comes out of a pipe above the water. I intend to connect an exhaust hose to this pipe and pipe it overboard. When the engine is in gear, the exhaust is injected into the water alongside the prop.

    ReplyDelete
  10. What about engine steering?
    With it mounted that way it would help in some situations such as docking into the wind to be able to push sideways with the engine at 90 degrees or more. At more than 90 shifting forward/reverse may not be needed. No need to stress the bow line or need a spring line just to power the stern into the dock.
    If the engine is tiller steered does it disengage when raised?
    Which engine? I thought most current outboard engines exhaust through the prop hub. Or is that only the bigger ones?

    ReplyDelete
    Replies
    1. The engine will not turn at all, for a few different reasons. It doesn't work like you'd expect; in fact, it doesn't work at all. The engine well is too narrow. Pretty much any outboard in the 25-50hp range will work, with a lower-pitch prop. They all exhaust through the prop when in gear.

      Delete
    2. Proper KISS engineering. The only worthwhile improvement is simplification.

      Delete
  11. I'm onto 5 months of cockpit time in our (wheel steered) sailboat, and so I can say with some authority that your design looks very good! I do have a few questions:

    1. Your early design included a big roof for shade and lots of PV. Do you plan to use a bimini too?

    2. Will there be any PV, or will most/all power come from wind turbines?

    3. If water gets into the backrest lockers, is there a provision for them to drain?

    ReplyDelete
  12. I haven't reintegrated the bimini yet, but plan to. I think that there is easily room for 400-600W of solar.

    The lazarettes will have limbers that will drain into the cockpit well.

    ReplyDelete
  13. From Dave Zeiger via email:

    Cockpit looks great. One option, given the parallel, longitudinal lines is sliding structures. A thwart, for example, or a frame for a fabric Bimini (accordianed out between the forward dodger and sliding frame).

    On our boats, we've extended the cockpit aft to the rudder post. In light weather, we sit aft, with low tiller leverage. As things pick up, we slide the thwart forward for improved leverage. Meanwhile, between it and the fixed, aft seat, it makes a great ripping notch or support for projects.

    ReplyDelete
  14. Your outboard will be very exposed when working in shallow water and will risk ripping the leg off when it strikes bottom with the momentum of a fairly heavy vessel, as you say the design allows no kick up. The greatest risk will be when you are running with fair current in muddy water. I suggest you make a habit in such circumstances of running with the boards well below the outboard as an 'early warning' and be ready to immediately kill and haul the OB. You might also consider having a pair of big sweeps, or if you're alone, a sculling oar, to manage the boat going downstream. You can also use the looms of oars (never the blades of course) to pole on the bottom or bear off a bank.

    ReplyDelete
    Replies
    1. The engine is positioned so that it doesn't protrude beyond the lowest part of the bottom or the rudders with the blades retracted. But it's not a bad idea to spring-load the engine track at the bottom, so that there is an additional line to horse it all the way down that's easy to uncleat, causing the engine to come up. You are right that in shallow water the boards should be partway down, so that there is some warning before running aground.

      Delete
  15. Just arrived here from the interview with Herr Kieser [giggle]
    Course for sometime now I've understood that should matters get out-of-hand here in Manhattan, in the range of X-class solar flares aka transformer shut-down at Indian Point Nuclear facility, or flooding during my 110th birthday. The only way out is going to be sailing. Community Sailing club here I come. Thanks Dimitry.
    also found this on the bloggersphere: The Peoples Cruiser
    http://volkscruiser.blogspot.com/2014/01/is-this-year-of-trilo.html

    ReplyDelete
  16. This is a really interesting project. I wanted to comment about the concrete bottom but on that post comments are not allowed. Excuse me for commenting on it here.

    There's a way to post stress concrete to make it super strong. They use it for concrete slabs in the building trade. It dramatically lowers the amount of concrete needed and also lowers the amount of re-bar needed. Here's a link to a page. Also search google for concrete stress cable and Post-Tensioning Concrete. The first search term will give you pictures of what the cable looks like.

    http://www.concretenetwork.com/post-tension/basics.html

    The way it works is a steel cable is coated in plastic and laid into the concrete when poured. After it dries the cable is pulled tight. The plastic is like a bushings or conduit way that the steel cable slides in. It stresses the concrete throughout the structure.You can buy the cables or it would be easy to make them yourself out of steel cable covered with liquid rubber or plastic.

    Why am I saying this. You might could make the whole thing out of concrete. Top too. Search for "Fabric formwork". Look at this link.

    http://www.fabricforming.org/images/papers/Veenendaal,%20D.%20History%20and%20overview%20of%20fabric%20formwork.pdf

    Another

    http://www.atkinsglobal.com/~/media/Files/A/Atkins-Global/Attachments/sectors/buildings/library-docs/technical-papers/Concrete%20structures%20using%20fabric%20formwork.pdf

    If you search for "fabric formwork" you get some excellent pictures of amazing stuff. Another method of fabric formwork is to drape cloth and spray it with plaster. This link shows the hanging fabric panels. The panels can be used as sprayed or even better used as molds or concrete forms.

    http://www.fabwiki.fabric-formedconcrete.com/doku.php?id=fabwiki:research:research_efforts

    Makes you think doesn't it. You could form the whole hull from hanging fabric and spray with plaster or concrete. This would form a mold in small sections. The sections are then wired, bolted, roped or whatever together. Stress cables are added and then the whole mold is poured with concrete in one big pour. Advantages are the molds are light weight and can be formed by natural draping of the fabric. Concrete with some plastic or metal reinforcement is super tough and long lasting.Post stressed takes away the worry of tension as most stresses on the hull are tension anyways the added cables would make the concrete strong. Hulling by hitting something would be very unlikely as the concrete is strong and it could be very thick as it's needed for ballast anyways. Another idea is to make the concrete even thicker and use light weight concrete. Usually added perlite, vermiculite or foam. Millions of pounds of this stuff are poured every year. A lot of it is used for insulation on top of malls and other buildings. With a super thick concrete hull made of lightweight insulation you wouldn't need any insulation it would be built in. Repairs are as simple as spatualing on a little cement. A few metal inserts could be added before the pour and be cemented in place. If you used lightweight concrete I bet it wouldn't sink. Couldn't sink. That to me is one of the most important things. I can't believe that anyone builds boats that if they fill with water sink but some do. I think it's stupid. The first rule of making boats is that it should just not ever sink. And finally it would just be dirt cheap. You could even make all the interior out of cement and pour the whole thing in one big pour. After pouring and drying you coat the concrete surface inside and out with a good epoxy paint and you have a trouble free surface for a long, long time.


    ReplyDelete
  17. My apologies again. I didn't see this site until the other day. I'm now commenting on the tiller post. Your tiller spring idea is excellent. I really like it. The idea is I assume to not have the tiller forcefully whack you if a wave hits the rudder. Another way to do this is to operate the tiller with a rope. A rope would be tied around the tiller where you hold onto it. Route the rope in a circular circuit through the cockpit with bearings or rollers. It could even make a circuit into the cabin, the front of the boat, or where ever you wanted to control the boat from. As the rollers would have little friction pulling the rope one direction would turn the rudder one way and pulling the opposite the other way. As you can readily let go of the rope if the rudder is hit it wouldn't damage anything. This also gives you infinite placement of control of the boat as the rope can be routed wherever you can fit bearings. If you wanted to vary the ratio of rope pull to tiller movement you could get rid of the tiller lever arm all together and make a Chinese windlass. On this page look at the first drawing of Differential windlass.

    https://en.wikipedia.org/wiki/Windlass

    See the ropes labeled S and S'? Those would be the ropes routed through the cabin or where ever. As you see there's a pulley or sheave labeled R. As you can imagine you could have any number of these pulleys routed all over with the rope making a control circuit to the rudder where ever the rope went. The ratio of rope pull to rudder movement could be whatever you wish. Just like a wheel but cheap and routable.

    Now I know you've centered on wood for the boat shell but I've been thinking about concrete. I love the idea of all concrete (actually cement) because it's so cheap that anyone around the world could do it. Yes I know I'm babbling. The key is to pre-stress the concrete. I got to thinking about wires first but then started thinking about rope. Rope can be made out of grass if necessary. Now in the modern countries we would use something better but just for fun I'm thinking about what people could do in a developing country with next to no money.

    Here's a guy that knows damn near everything there is to know about molding cement and ferrocement. Look at this page and you'll see he does beautiful work sand casting cement. (he also has a lot of other good pages)He says that when he sand cast it makes the cement stronger as the water runs out in the sand compacting the cement unlike forms which hold it in.

    http://harmoniouspalette.com/SandCastStone.html

    As you can see on the page fairly complicated curved structures can be made easily with this method. My thinking is you make sand molds in sections. The middle of the boat would just be repeating sections. The bow and stern would have to be done as one offs. A thin shell would be made. All the shells would be stood up and connected. cont.

    ReplyDelete
    Replies
    1. You would then need to add the rope or wire post-stress cables. To do so you use rope wrapped in cardboard or paper. Why the cardboard or paper? The rope will need to slide in the concrete channels to be tensioned. The cardboard would keep cement out of the rope or cable grooves that are in the rope. These are laid in the assembled cement shell in the same pattern as a fishing net and (most importantly) exiting the hull. Any breaks in the rope must be out of the hull on the top deck for easy inspection.

      Now you may say this is the dumbest thing I've ever heard. Boats held together by rope but that's the way the ancient Greeks and the Egyptians held together their boats and with the modern ropes we have it could be very strong. Here's a video showing exactly how they sew boats together.

      https://www.youtube.com/watch?v=xtpZPvpRMr4

      The strength could be very large using modern materials but basically I would rather use normal stuff like nylon rope. Here's a page of the tensile strength of various materials.

      https://en.wikipedia.org/wiki/Ultimate_tensile_strength#Typical_tensile_strengths

      The Ultimate tensile strength(MPa)of wood is only 40 MPa. Nylon fiber, drawn is 900 MPa. If you really wanted to get the super stuff Kevlar is 3757 MPa. After you lay in the rope tensioners you spray over them with cement from a cheap cement sprayer. Ribs and flooring could also be sand cast and all tied together with cement then sprayed. After it dries pull the ropes tight and tension the whole shell together. Notice I said to make loops outside of the hull. Each loop could be tightened with a chisel or lever put under the rope then pulled up to tighten the rope. The rope then bound in with a wedge just as shown in the video I linked. Also having the rope showing you could tension the ropes further with wedges if the rope or cable stretches.

      With the panels sand cast you could even make the panels honeycombed. It's unbelievable how strong honeycomb structures are. Ever seen honeycomb cardboard. You can stand on pieces made of the same thickness as a normal cardboard box.

      https://en.wikipedia.org/wiki/Honeycomb_structure

      I picked up a F-16 horizontal stabilizer one time. A guy asked me to help him pick it up. I bent my knees and picked it up expecting it to have some weight as it was fairly large. It weighed nothing. I was astounded how little it weighed. It made of honeycomb with thin skins.

      Once again my apology's for posting about cement when your using wood but I looked at some of your wood cost and had to at least discuss the idea that there might be another way.

      I do think the rope controlled tiller would work well though.

      Delete
  18. I have an idea about the ballast also. Some of your ballast is water ballast and some you say you're going to use concrete. The concrete is just pure weight and adds no purpose. It also can't be dumped if you're marooned on a sand bar, rock or whatever. Why not use ALL water ballast? Yet make the water useful. A tool. All the water ballast would be in a box. Inside the box would be a rubber or butyl FRESHWATER bladder that almost filled the box. As you use the fresh water you could pump sea water into the box surrounding the freshwater bladder. Hence the amount of ballast never changes. You could start out with a huge reserve of freshwater compared to a normal boat while never compromising the boats ballast which would stay the same weight all the time. If you get somewhere where the boat needs to be removed from the water and freshwater is available you could dump all the freshwater and seawater ballast making the boat super light, in comparison to a huge concrete rock that you can't remove. If you get stuck on some rock or bar you could dump seawater ballast to get unstuck. Would be a good trick for beaching. Fill the seawater ballast as full as possible and run up on the beach. When you want to leave pump it out at high tide and float off. You could always fill it up after you're at sea.

    ReplyDelete
    Replies
    1. I looked around a little and found these guys, who I have no financial interest in, and wow they have bladders covered.

      http://atlinc.com/pillow.html

      I also noticed they have fuel bladders. Hmm...you could also build boxes and place the fuel bladder in and cover with sea water. As the fuel declines pump in sea water over the bladder in the box. The great advantage in the sea water bladder idea is you're carrying maximum fuel, water, etc. when you start and never just losing space to ballast that serves no purpose. Sea water could be pumped from front to back to trim like an airplane pumps fuel from wing to wing.
      The lifetime of the bladders should be great. Think of inner tubes in tractor tires. They last a long time with great stress on them. Since they're in boxes they'll be easy to drain and remove if needed. You would need to strap them down and maybe have a liner so they wouldn't rub on the box.
      Fluids also make a far better heat storage mass than any rock or concrete. Water is the best heat storage material there is.

      Something interesting. There's guy named Michael Bradley who built floating pontoon boats in the third world for fishermen. He simulated the balsa logs they used to use with foam. He had a great idea. He used a windmill to turn a prop. That way no matter which way you went as long as their was wind it was efficient to travel.

      http://www.michaelbradley.info/lowtech/windmotor.html

      http://www.michaelbradley.info/articles/windmills1.html

      This always interested me. Since the windmill is self starting and sort of furls itself with higher winds. A gear off of the bottom, or rope or belt drive, could also drive an alternator charging the batteries. Since it self furls itself you could have very large wind sails for low force winds which would also work for large winds. In a storm you could head which ever way was safest instead of which way the sails turned you. If you fed power to the propeller you could maneuver the boat in the storm. Changing the whindmills opening could regulate power to the propeller. If you made the windmills sails rectangular then if all else fails you could turn the sail into a somewhat inefficient Chinese junk sail and carry on.

      Micheal Bradly has a good page on speculative curragh ideas which is right up your ally. It's called,
      "Hot Air and Ancient Wonders: Technology for dummies, or building massive monuments and surviving the coming social Deluge"

      http://www.michaelbradley.info/books/hotair/hotair1.html

      Delete
  19. Hi Sam,

    Thanks for your thoughts, but I think you are mostly thinking about some other design, not QUIDNON, which is fiberglass over plywood. Concrete has been discussed and abandoned.

    One comment: the tensioned spring in the rudder linkage is to avoid damage in case the rudder strikes GROUND, not water. If the spring can be flexed by waves, it isn't tensioned right.

    ReplyDelete
    Replies
    1. My apologies. Got a little carried away. Some of what I was doing was just thinking out loud. I've always been enamored with the idea of a cement boat because of it's durability. As you said all that that tying of the wire up and making sure the cement is done in one big pass is the stopper. If someone could make a cement like MgO which sticks to cardboard, was easy to work with, decent cost and most of all consistent it would be the thing to have. Alas...

      Yes I totally missed the tensioned spring ideas purpose. It's a very good idea you have there.

      QUIDNON looks excellent. I sure it will be fabulous.

      Delete
  20. Hi,
    Have you seen the rope hinges at http://www.yrvind.com/present_project/

    ReplyDelete

Comments not directly related to the Quidnon project will be deleted.