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  #31  
Old 10-04-2011, 06:38 PM
Petros Petros is offline
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Quote:
Originally Posted by Richard Woods View Post
But can you carry 3-4 people and sail offshore in a USD55 SOF boat??
of course not, but the one I built was not designed for that either. I can design and build a perfectly seaworthy open SOF boat for about $1000 worth of materials. Sure you will have to treat it differently and be careful about rough landings on rocks, but that is not the kind of beach you would want to land a fiberglass boat on either. You would also have to replace the skin every few years or so.

To PDB a couple of questions:

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What is your sailing experience?
Not as much as some, I have been on the water in my own small craft since I was 11, did a fair amount of recreational club sailing as crew, built 14 small boats, have owned 18 different boats. None had motors, all were either sail, paddle or oar powered. Not a lot of deep water experience except off the california coast.

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Would you cobble together a car made from USD500 worth of scrap parts and then drive it across (say) the Australian outback, knowing that if you broke down you would not get rescued??
Yes I would and I have, one of the challenges I find fun. On one such trip I bought an old, non-running toyota for $100 in Colorado, fixed it with the tools I had with me in a day, and drove it 4000 miles across the USA and back to Puget Sound with a few minor repairs along the way. I am a very experienced engineer by profession, and work on old cars and sailboats by for fun.

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Originally Posted by Richard Woods View Post
Do your three friends know how little you will be spending on the boat they will be risking their lives on??
The inexpensive small boats I have built are used in inland waters, and everyone that has been on them knows that I built them inexpensively. Cost does not always reflect quality, especially on a home built. Had I choose to build a boat for doing long open water crossings they would be designed very differently, cost more and take more time to build. It is about carefully designing to the conditions, and to the properties of the materials be they wood, fiberglass, steel, aluminum or other materials. As you know a wood boat is not inherently weaker than a fiberglass one. And SOF is not inherently inferior to a plywood hull.

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Originally Posted by Richard Woods View Post
I know that you won't get far with a SOF catamaran in the English Channel.
Perhaps, but I have never sailed the English channel, so I would not know. I did not design any of my boats for those conditions.
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  #32  
Old 10-04-2011, 06:53 PM
Percyis Percyis is offline
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Quote:
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Yes I have read the Brendan Voyage. I have also lived in SW Ireland and seen modern currachs. I always wonder how many traditional boats didn't come back from a days fishing. And how many oldtimers would prefer a boat built in modern materials, given the choice.
About those folks who never came back... I wonder the same thing about people who drive away from their homes in modern autos, only to never return to their families because of an ugly twist of fate. I wonder the same thing about catamarans, monohulls, trimarans and every power boat ever made. I wonder about drinking while out on the water. I wonder about rogue waves, heart attacks, gout and any other oceanic malady one can muster. The point is... humans will find wildly creative ways to off themselves and there is not one thing you can do about stopping it from happening, SOF boat, or not. Go to sea on a cruise ship with a hundred doctors and you can still die while on the water. Red Herring even kill people.


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Originally Posted by Richard Woods View Post
The Top Gear cross channel trip had several rescue boats at hand (in fact I believe that one car sank)
Pretty much irrelvant, actually, since the primary truck made it across in good form and even drove up the launch ramp on the other side. The point being that one should keep an open mind when thinking of a solution to what was presented as the major problem of negotiating the Channel.


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Originally Posted by Richard Woods View Post
I agree with all Peter Chech says. I had a friend who had fabric decks on his dinghy. One day he slipped and put his foot through the deck. Then he capsized. As they say, s**t happens.

Stories of boats are everywhere, Richard. Give me a day to check it all out and I'll send you a couple of dozen reports that cast ugly shadows on any boat type you can mention. If you have wood, it rots. If you have glass, it blisters, if you have carbon fiber, you have to avoid point load sources and sunlight exposure. The list goes on and on showing that there's no such thing as the perfect boat building material. Only materials that present options based on cost, ease of build, and lastly... on one's personal preferences, which are more than likely squeezed out of the emotions. To dismiss a type offhand is to confine one's optons to a smaller circle of potential solutions. I'm not inclined to go in that direction.




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Originally Posted by Richard Woods View Post
Coastal sailing is much harder on a boat than is ocean sailing. You have to anchor regularly (and in the English Channel (La Manche) tidal ranges are up to 40ft), so you need lots of warp, chain and a sharp fluked anchor. None of which are kind to a fabric hull. I'd also be very, very nervous about carrying any stores in the hulls, just because of skin wear and rips.
So, you find it impossible to build a reenforced box for the ground tackle and anchor setup.... One that keeps the pointy stuff from wailing away at the fabric? Same for the stores. I think that is boat handling 101 when you see that something isn't working so well all by itself. It seems that a prudent person would just adapt and move on. end of problem. Every year, thousands of inflatable boats make really tough trips down major, Class 5+ whitewater rivers. The hard edged stuff goes into containers aboard the boat and miraculously, it comes out the other end of the river trip intact. Stuff like shovels, weapons, crampons, axes, etc. and the reality of having a damaged boat from those items is as close to zero as it can get. I don't see the issue here.


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Originally Posted by Richard Woods View Post
I have designed and owned catamarans with rope lashings. But that doesn't make them SOF. I also helped build and later extensively sailed the protoytpe Wharram Pahi 35, which had rope lashed beams. We had to keep changing the lashings because of chafe and they creaked and groaned, which was disconcerting at best.

30 years ago I built a 25ft racing catamaran using 4mm ply over stringers/frames. So maybe that could be considered SOF construction. It is still sailing. We didn't worry about capsize but did worry about hitting flotsam, especially when sailing fast at night. We sailed it extensively up and down the English Channel. Our best sail was 135 miles from Plymouth to Southampton in 13 hours.

I suppose that you could refer to just about any boat on the water as skin on frame, if you look at it sideways long enough. Since the type is the basis for pretty much every craft that did not come from a hacked away log, the thread is long and continuous. I do find it interesting that you are going out of your way to argue against the genre, even though you have lashed a few boats in your days at sea.

From my experiences on the water, all boats make disconcerting noises from time to time and until one gets in the rhythm of the form, it remains uncomfortable. This includes everything from all-carbon racers to inflatables so I'm not surprised that you got spooked. I sailed back to L.A. from Costa Rica on a wooden schooner and day in and day out it made all sorts of creaky sounds. The boat ran well, sailed smoothly and made port in decent time with no problems, save for a cook who was awful.

By far and away the longest early voyages were done by the Polynesians aboard craft that were held together with lashings. Chafe and adjustments were just part of the game for those boats, and yet, they traveled enormous distances on wide open seas in all types of weather to locations that are the most remote on the planet. No fiberglass, no bolts, no mathematical degrees to calc the loads, just pure sailing skill and experience building boats that worked. How did they do it with such creaky ill-advised boats?


Quote:
Originally Posted by Richard Woods View Post
The OP has a very low budget, so I doubt if he will buy professionally drawn plans. After all the Tiki 21 plan price is about USD550, or half his total budget... In his place I'd buy a used monohull.
At last, we have a sensible option upon which we can agree.
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  #33  
Old 10-04-2011, 07:59 PM
paradoxbox paradoxbox is offline
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i've been checking out gary dierking's designs and i have his book on sailing outrigger canoes

i don't think that i'm "all over the place", basically i'm just open to many kind of designs. my requirements are not that difficult or wild - as many people have so far mentioned the polynesians did what i'm thinking of doing with ultra simple designs over far greater distances, without the aid of modern materials or technology. if they could do it so can i.

i also think it's important to understand that the okinawan islands are not very far apart. people routinely make the island hops in kayaks - if people can paddle it in a day in foldable kayaks there's no reason a small sailboat cannot do the trip. i'm not crazy enough to go out island hopping in anything but great weather in such a lightly built boat, but at the same time a monohull just won't work well in the area, i need something more portable and there are draft issues to consider (corral reefs everywhere). i also do not want to be burdened by monohull ownership problems. this is japan, boats are extremely expensive and powered boats require licenses here, but a disassembling sailing cat or proa or tri will not be bothered by the taxman and won't need moorage either.

there is the consideration that i need (want) to be able to have the boat nowhere near the water during typhoon season - it's far safer to unlash the parts and store it behind a typhoon wall which the locals build around their houses here.


i agree with the 400-500lbs weight for beaching ability, but i also intend to disassemble the boat if i beach it so it might be OK if it's heavier as long as I can keep the bow end of the boat on shore while i undo the lashings and haul up the hulls individually. okinawan beaches are pretty flat.

as far as lashing noise etc.. for me that's part of the fun, i don't mind it - remember i'm not doing huge cruises, we're talking about trips that are generally going to be less than 20 miles, from one island to another. a multihull ought to be fast enough to do that trip in half a day or less. only sometimes will it need to be able to make the 120mile trip from the okinawan mainland to the yaeyamas. that will of course be a special journey with special preparations.

keep the discussion coming, lots of interesting new thoughts and ideas, i love it. especially will check out the ndrua designs and the wa'apa for more ideas.

map of okinawa with a line showing the longest planned passage
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  #34  
Old 10-04-2011, 08:52 PM
Petros Petros is offline
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I also want to add that the Aleutes and the Greenlanders used skin on frame boats in some of the harshest environments in the world, they depended on them for their very survival. They covered hunderends of miles in them, from single seat kayaks to 35 ft plus umiaks.

I like the efficiency of SOF so much I am contemplating building a pocket sized coastal cruiser to see how far the concept can be pushed. With rub rails and similar precautions there is no reason to think it will not be as durable as any other type of construction.
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  #35  
Old 10-05-2011, 09:59 PM
peterAustralia peterAustralia is offline
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something like this

http://www.duckworksmagazine.com/09/...ejak/index.htm


but extended by 4 or 5 ft would work
still dont think you could do it for $500
gee an eBirb costs that alone

$3000 maybe.. $500 not really

I think the above craft extended would be about the best value for money boat you are likely to get. If only that be my opinion, and not fact
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  #36  
Old 10-06-2011, 04:22 PM
peterchech peterchech is offline
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That's interesting. Makes me think, a bolger light dory with outriggers might be functional, if still limited to hull speed. But for $500-$1000, few multihulls would cruise faster than 6-7 knots anyway I imagine...

A monohull with outriggers gets you some better load carrying capacity.
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  #37  
Old 12-23-2011, 09:23 AM
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Delane Delane is offline
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Paradoxbox,

I've Sailed in Okinawa for 22 years and may be able to shed some light on the subject of weather, reefs, ports, and a host of other disciplines of navigating these waters. Plan to spend more money on the project as nothing is that cheap and relative safety should be paramount. Also have 7 different mast to choose from (all aluminum) and could make you a sweet deal on one of those. Are you in Okinawa now? I have a Trimaran at Kadena Marina.

Delane
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  #38  
Old 12-23-2011, 02:03 PM
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Richard Woods Richard Woods is offline
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Many traditional SOF boats used leather as the skin. That's a very tough yet flexible material, still to be bettered by manmade materials. Remember motorbike riders wear "leathers" to help prevent injury when they fall off. They don't use kevlar or other high tech materials

But it's heavy and although I haven't priced a cow skin I suspect it costs much more than a sheet of plywood

Richard Woods of Woods Designs

www.sailingcatamarans.com
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  #39  
Old 12-23-2011, 04:50 PM
CatBuilder CatBuilder is offline
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One thing I'm noticing is that seems like a wonderful cruising ground. It just made my "someday" list.

Another thing I'm noticing is that the OP is in Tokyo.

I'm not sure you can even buy a dinner at a nice restaurant for a family for under $500 in Tokyo.

Where will you build this boat and where will you find materials for less than $500 in Tokyo? I think that is what will kill the economics of the project.
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  #40  
Old 01-16-2012, 05:19 PM
Harry Josey Harry Josey is offline
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It seems that $1000 is too little and 3mm is too thin. It looks like you are stuck with skin on frame. After all coracles have crossed the Atlantic. I agree that usng SOF from the beach is a little daunting but our ancesters did it all the time. I think I can help solve that problem.
Back in the early days of fibreglass(the fifties) a number of boats were built using SOF as an armature or integral mould for a glass fibre lamination. The timber and fabric can be very cheap because they will be completely escapulated. I built a boat using this method so will quickly describe the method.
A stem, hog and transom were set up over cheap mould frames. These timbers remained in the finished boat but there is no reason for them to be expensive. Stringers were then screwed to the stem and notched into the transom. As they were to be included in the finished hull they were only tacked to the mould frames with panel pins. the number of stringers isn't important but the more there are the stronger and fairer the finished hull would be. It would also be heavier and more costly. Fabric was then stretched over this frame. On small boats the fabric was muslin on larger craft
a some what heavier cloth was used. Once fixed the fabric was starched. This served to both tighten and stiffen the cloth to receive the fibreglass. The first layer of mat is going to be resin rich as it couldn't heavily rolled out.
Once this had set subsequent layers could be worked normally. We didn't use
much cloth in those days, it was expensive and difficult to wet out. We developed a number of ways to produce a fairer surface. Once the lamination is thick enough on the outside of the hull thickened resin was applied with a spackler or flexible paint scraper and then sanded. the hull could then be rolled over and the mould frames removed from the inside. The pins were then cut off and the whole of the inside laminated with a layer of mat. Bulkheads and decks can then be fitted. As it is difficult to laminate the underside of decks it is better to partially complete them before fitting them for the final laminations. The resulting craft will be heavier than a lightly built plywood or foam cored boat but it is easier to build and is surprisingly tough.
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  #41  
Old 01-16-2012, 07:41 PM
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BATAAN BATAAN is offline
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Quote:
Originally Posted by Harry Josey View Post
It seems that $1000 is too little and 3mm is too thin. It looks like you are stuck with skin on frame. After all coracles have crossed the Atlantic. I agree that usng SOF from the beach is a little daunting but our ancesters did it all the time. I think I can help solve that problem.
Back in the early days of fibreglass(the fifties) a number of boats were built using SOF as an armature or integral mould for a glass fibre lamination. The timber and fabric can be very cheap because they will be completely escapulated. I built a boat using this method so will quickly describe the method.
A stem, hog and transom were set up over cheap mould frames. These timbers remained in the finished boat but there is no reason for them to be expensive. Stringers were then screwed to the stem and notched into the transom. As they were to be included in the finished hull they were only tacked to the mould frames with panel pins. the number of stringers isn't important but the more there are the stronger and fairer the finished hull would be. It would also be heavier and more costly. Fabric was then stretched over this frame. On small boats the fabric was muslin on larger craft
a some what heavier cloth was used. Once fixed the fabric was starched. This served to both tighten and stiffen the cloth to receive the fibreglass. The first layer of mat is going to be resin rich as it couldn't heavily rolled out.
Once this had set subsequent layers could be worked normally. We didn't use
much cloth in those days, it was expensive and difficult to wet out. We developed a number of ways to produce a fairer surface. Once the lamination is thick enough on the outside of the hull thickened resin was applied with a spackler or flexible paint scraper and then sanded. the hull could then be rolled over and the mould frames removed from the inside. The pins were then cut off and the whole of the inside laminated with a layer of mat. Bulkheads and decks can then be fitted. As it is difficult to laminate the underside of decks it is better to partially complete them before fitting them for the final laminations. The resulting craft will be heavier than a lightly built plywood or foam cored boat but it is easier to build and is surprisingly tough.
That is so amazingly cool. What an ingenious and obviously effective to build a long-lasting F/G boat.
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  #42  
Old 01-17-2012, 03:09 AM
Harry Josey Harry Josey is offline
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Sof Fibreglass

Alas the finished result didn't look sleek & shiny like a "proper" fibreglass boat,fresh from it's expensive female mould. After all the real purpose of a boat is to stand proudly in the drive or the dock to impress ones friends! Has anyone worked out the percentage of boats that never get wet or leave the marina?
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  #43  
Old 01-20-2012, 02:17 PM
peterchech peterchech is offline
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wouldn't a used beach cat do pretty much everything the op is asking for? I mean 20 footers regularly cross the atlantic, though at its shortest point... hard to find one for $1000, but not impossible either...
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  #44  
Old 01-20-2012, 04:51 PM
Gary Baigent Gary Baigent is offline
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A most underrated boat (although not by a few enlightened sailors) is the Piver Nugget 24. You can pick one up very cheaply (usually horribly modified with over built, top heavy cabin and other nonsense) - but most importantly check that the ply is in reasonable condition ... and THEN you gut it, make it flush deck with a shallow cockpit and/or put a small cuddy on it (pretty much as Piver had with the original) then a decent daggerboard and better rudder setup, get rid of the silly float fins and then find an alloy mast (or build a small wingmast) ... and you'll end up with a very good sailing design (that will shock many other yachts with its windward performance) and you'll have it for minimal expense and some (enjoyable) backyard work.
Here's my sailing mate Jacques de Reuck's modified Nugget (in the foreground, the traditional in back is an L Class Mullet boat) - this Piver has a cockpit from stern to mast step - which makes it a really great sailing boat.
Attached Thumbnails
An extremely cheap, easy to build proa, cat or tri for Okinawa island hopping?-lclass5.jpg  
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  #45  
Old 01-20-2012, 05:21 PM
Silver Raven Silver Raven is offline
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Originally Posted by Gary Baigent View Post
A most underrated boat (although not by a few enlightened sailors) is the Piver Nugget 24. You can pick one up very cheaply (usually horribly modified with over built, top heavy cabin and other nonsense) - but most importantly check that the ply is in reasonable condition ... and THEN you gut it, make it flush deck with a shallow cockpit and/or put a small cuddy on it (pretty much as Piver had with the original) then a decent daggerboard and better rudder setup, get rid of the silly float fins and then find an alloy mast (or build a small wingmast) ... and you'll end up with a very good sailing design (that will shock many other yachts with its windward performance) and you'll have it for minimal expense and some (enjoyable) backyard work.
Here's my sailing mate Jacques de Reuck's modified Nugget (in the foreground, the traditional in back is an L Class Mullet boat) - this Piver has a cockpit from stern to mast step - which makes it a really great sailing boat.
Gary - Great looking modified Piver - KISS principle - Thanks for posting. Would think that's great value for dollars spent & suprises many people when it goes past them - wonderful example of cost effective - fun & lots of sailing & all for only $3K or so. WOW I am very impressed. Caio, james
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