Minimum cruising cat-size & cost

Discussion in 'Multihulls' started by Alex.A, Feb 24, 2010.

  1. catsketcher
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    catsketcher Senior Member

    Coastal is different

    Gday Alex

    I am pretty sure you can do fine with a 9 metre cat especially along the coast. I think that a cat is a really good boat for coastal cruising for wimps or people with families on board. You can hide in rivers that have barred entrances and when conditions are good whiz along to the next spot where you can tie to a tree. You just need a different way of thinking.

    I was happy enough living on a very small tri with my wife and kid.

    BUT I wouldn't go crazy with the rig or the boat. The crab claw rig will be more expensive than a secondhand normal rig. I would urge you to be circumspect in the new ideas you put into the cat. I talk from some experience of failure of the novel.

    For Kankama I had all these new ideas - she was going to be like no other cat.

    - inverted flotation - After owning a Twiggy (they did capsize a bit in the 80s) I wanted inverted flotation fore and aft. It was pretty easy to get inverted flotation up front but down back I made a big 1.6 by 2.0 metre box instead of a cockpit to keep us afloat upside down.
    -swinging davits - that was a good one - they swung into the path of the mainsheet during a gybe
    -vertical tiller - a godsend on a Twiggy but stupid on a large cat
    -air stuts on the dodger roof to raise it to headroom height - oh man - it just looked really crazy when up that high. I could not bear the thought of my boat looking that dumb.
    -wishbone boom - absolutely bloody brilliant bit of a kit for a big cat. You should all get one for cats over 35ft.
    -no spreader rig with inner forestay - love that storm jib on the inner forestay when the wind is up. Fits right in with the wishbone. Synergy.

    Only two good ideas and they weren't even mine. All the crazy ones have been sawn off and replaced. Now Kankama is a pretty normal looking cat (albeit with a wishbone but I do love that thing).

    If you want to save time and money build something similar to what other people are doing and BUY someones plan. You will save truckloads of both.


    Phil Thompson
  2. Alex.A
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    Alex.A Senior Member

    Hi - thanks Phil - just running through the options and learning....
    Want to follow this thought through as far as possible because there are a lot of people who'd like a decent boat at less cost - also many (it seems) who are interested in new and different idea's ie crabclaws and wondered if there's anything in it?
    Have no plans to self design, only self build! and will probably go with normal rig anyway....
    It's like pc's - there's windows and everyone uses it because everyone uses it- and it's not the best solution.
    There is little in the mkt for different though - why? Cant be because there isn't a mkt for it - no matter how small - and obviously designers design for what will sell, after all they need to make a living.
    I also come back to a very important part of the whole process - a boat that is practical, capable and also appeals and thats what i am still searching for.... I live in a third world country- no matter how much it pretends it isn't and feel that cheaper solutions would get more people back on the water- new and old.
    I also like fanie's aftmast idea's but it wont necessarilly be any cheaper than a conventional rig.
  3. rayaldridge
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    rayaldridge Senior Member

    This is excellent advice for 99.9% of builders, but I'd hate for it to be 100%.

    From the viewpoint of a novice designer who's never going to make a business out of the craft, I'm just not interested in doing something that someone else has already done-- and probably done better.

    Of course, the risk (and really, the certainty) is that some of your efforts will go horribly wrong when you restrict yourself to original design. But that's the price paid for progress.

    I've never been interested in gambling, and I lived for several years in Las Vegas. But these days I can sort of see the appeal. When you try to build something that hasn't really existed before, you at least have a chance at a jackpot, though more than likely you'll come up snake eyes.
  4. terhohalme
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    terhohalme BEng Boat Technology

  5. catsketcher
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    catsketcher Senior Member

    Beware the innovation!

    I agree with you here Ray. I reckon you have gone about it the right way with Slider and your new boat.

    1 - You put your own money where your mouth is. There have been a few designers (mostly out of the scene now) who used other people's money to innovate. That can be dangerous when done in the extreme. One innovative new cat I tried to test wouldn't tack due to its breakthrough rudder design!
    2 - You kept it small. If Slider didn't work then you would be able to pass it off as an interesting little sidetrack. If she was 32 ft then she would be a significant dead end in your life.

    My advice for anyone thinking of new rigs, different foils, etc is to do it small if they have to do it. Your first approach probably won't be your best.
  6. rayaldridge
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    rayaldridge Senior Member

    Phil, I appreciate the encouraging words. I tried my best to make sure every element of Slider was in line with current thinking, except for that one weird idea-- seating in the hulls of a 16 foot cat. I was mightily tempted along the way to try all sorts of other ideas, but I think a useful truism in design is to not have so many innovations that you can't tell what went wrong, should the boat turn out to be a failure.

    You're absolutely right about trying things out at a small scale first, and I think the original poster has mentioned that he might do so. The project I'm about to launch is sort of an approach to providing a simple platform for experimentation cheaply and easily. It's a 14 foot cat made as low-tech as possible, but with the hulls that were successful on Slider. The greatest innovation on the new boat is the barndoor rudder system, and it may be that it won't tack any better than the boat you mentioned above.


    But if it works, it will be a real cat, with fairly modern hull forms, that can be built for 500 bucks, will sail in 8 inches of water, and can be cartopped. It'll be a long time before I even draw plans for it, since I feel that any new boat ought to get a few months of testing in all the conditions it's likely to meet, before it's offered to builders. But eventually, if I can make it work, the plans will be very cheap, and I hope it will prove to be a platform for folks to try out new ideas without risking much time or money. You could put a biplane rig on it, like Tony Bigras did with Miss Cindy, for example.

    Anyway, small is beautiful, and much less risky, as you say.
  7. Alex.A
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    Alex.A Senior Member

    Phil - where do i find pics of your boat and whats your web adress?
    Ray - like the sounds of your new creation - slider too.
    Terhohalme - nice but well out of budget!

    Wharram has built a 27' version of wayfarer but dont think as cruiser - said it's for fishing.... will have to wait and see.
  8. ThomD
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    ThomD Senior Member

    One thing I really like about canoe sterns is the potential versatility in the ultimate storm (not an experience I can actually speak to unless canoes in whitewater or the great lakes count). My experience in small boats on very large lakes with cold water, and extreme storms is that often getting turned around is the nub of my problem. When I mentally sketch out how things might go and when I might want to deploy a para anchor, or a series drogue, and from which end of the boat, it isn't always the same end. Lets say you are tooling along under series drogue but worry about where you are drifting, do you want to switch out to a parachute which has to come from the opposite bow. Or if the parachute breaks, ties up, etc... I need to deploy my series drogue from the bow, but don't want to be making haste in reverse with flat or scooped ends. Lots of potential scenarios, when a boat that isn't entirely directional would seem an advantage. I don't think the Wharram really meets my needs because of the fixed rudders. But there are double enders, possibly with the rudders in cassettes that might provide a lot of flexibility.

    The main thing that makes me reject double ends is that over the 30 years I have been designing canoes and multihulls I have swallowed the kool-aid on bow overhangs, or flared hulls in many cases and have eventually come around to less poetic solutions that involve managing where I put the displacement. More displacement is good just like more beam in a multihull is good and the beam has doubled over the years. Whatever the solutions that something like the TIKI 30 provides. it is hard to not see the potential for a 26ish foot boat that would outperform it in every way including survival and cost the same to build. What about the 30 footer with the same dock fees and building budget? That is 30 feet on the waterline and carries a lot more volume, with less wind drag, etc...

    Yeah I can see what the overhangs and points do for me, but how much displacement could I occupy with the same pile of plywood if I designed it right?
  9. Alex.A
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    Alex.A Senior Member

    Space the only loss but then not everyone needs it and those that do have plenty of boats to choose from. There are a lot of couples and singlehanders that might go for such a boat? The rudders are a problem - would prefer to kick-up.... calls for lateral thinking. Underhung but still able to kick-up? Rudders could be set on inner side of hulls but hardly optimal.
    Why does simlicity have to be so complicated?
  10. rayaldridge
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    rayaldridge Senior Member

    Folks have taken a crack at kick-up spade rudders. One solution is to have the whole unit, transom and the aft part of the hull included, kick up.

    But for a cruiser, I think in many if not most cases, a transom-hung or outboard rudder will be adequate... and also simpler, cheaper, and easier to fix and maintain.
  11. Alex.A
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    Alex.A Senior Member

    Nobody has picked up on the looks thing.....
    Do people like canoe hulls ?
    And the there's the rounding of everything - complex shapes that take longer to cut out and fit - and then fit an interior to..... time is (more) money and more wastage? But square looks dated.
    Where else can costs be cut or time saved without too much compromise?
  12. marshmat
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    marshmat Senior Member

    Some people like canoe sterns, some don't. Personally, I like them, if it suits the boat. They do add LOA, though, compared to transom sterns for otherwise identical hulls.

    Fitting the interior is one area where there's a lot of flexibility in costs. The difference between paintable-quality and varnish-quality carpentry can be a factor of two or more in price and time. Do you need trim panels to cover everything, or are you OK with seeing frames and the hull? (I prefer the latter...)

    Outfitting and systems is another area where one might realize real savings. I recently read a review of one "cruiser" of 50 feet or so that had been optioned up with networked 3D chartplotters and the like- over $100,000 in navigation electronics. Would you be happy with a sextant, paper charts and a couple of handheld GPS receivers? And do you need pressurized hot and cold fresh water, or is a foot pump OK?

    Figuring out the absolute minimum you need to be happy and comfortable is certainly an important step in finding a suitable boat. A list of "must have" items should be separate from a list of "would like but can live without" items.
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  13. magwas
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    magwas Senior Member

    What do you think about this one?
    It is just a rough draft, result of a mind gymnastics inspired by the "tunnel effect" felt in a corsair F-24 (that is a great boat, do not misunderstand me). This is intended to be a trailerable planing hull, with as high BC as doable without being too cubistic, to be able to accomodate little more than a daysailer interior. I am thinking about putting the amas below the boat on the trailer.
    Another thing I am thinking about is longer akas, to make transverse GM match the longitudinal one. I would use a rack and pinion to outspread and pull together the amas, and place the akas a little out of symmetry not to bar each other.
    (Yet another thought is paralell rig placed on the amas. Junk rig, unstayed mast. Yes, it is far fetched, but it is just mindplay.)

    Attached Files:

  14. Alex.A
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    Alex.A Senior Member

    Definately paint not varnish! Keep it simple - no problem with prettyness - frames are fine. Less weight too. Basic systems but up to saftey specs. I need to spend less on the whole boat than they did on systems!!!!!!!!!!!!!!!!!!!!!!!!!!!
    Going cruising - not to space!
    One more silly question...... i have never seen a lapstrake cat - why not?
    Must be easier/quicker than strip planking and end up with a really strong hull. So is waterflow affected by ridges?
    Remember it's a cruiser not a racer......

  15. Richard Woods
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    Richard Woods Woods Designs

    I write some brief notes about multihull rigs on the articles pages of my website. There I explain why the sensible choice for multihulls is the single mast bermudian rig, either masthead or fractional rig.

    However many people want to experiment with alternative rigs so I thought these even briefer notes might help separate fact from romantic appeal.

    Most alternative rigs are based on those used on various working boats in use round the world.

    However one must remember that, unlike recreational craft, which need to be good all-rounders, those boats didn't just sail, they fished, or traded. The actual voyage was just a means to an end.

    So the Thames barge used a loose footed sprited mainsail. They used the sprit as a derrick when loading. the boomless mainsail could be brailed up when carrying lightweight but bulky cargo (usually hay for horses into London and horse manure back downriver to the Essex/Kentish farms). Few modern multihulls have to do that!

    The Chinese junk rig was developed in part because they used split bamboo for sailcloth, which had little intrinsic strength. Modern materials mean one can use different design techniques; it seems pointless to me to try to replicate something that was designed before better materials came along. After all, who now builds the interior walls of their house in wattle and daub, when sheetrock/plasterboard is better and easier, never mind cheaper? "Horseless carriages" didn't stay that way for long, they quickly became cars.

    The lug sail and other "asymmetric" sails (so including the Crab claw and Arab dhow lateen rig) were rarely used in conditions where short tacking was a requirement.

    For example, the "Looe Luggers" were fishing boats developed near to my home port of Plymouth. Fishermen would sail out from Looe on a starboard reach to the fishing grounds off the Eddystone. There they'd lower sails. In the evening they would hoist sails again and reach back home on port tack. A friend of mine rebuilt a Looe Lugger and initially rigged it with a lug sail. He only used it one season and then converted it to a gaff rig. Despite being very strong and fit he and his wife said it was just too much work to handle on a yacht.

    The Pacific islanders fished in a similar manner. Out through the reef in the morning on one tack. Lower sails to fish and then back home in the evening. So a proa made sense for them. They didn't have to short tack up the Solent or try to sail down the ICW.

    While I am talking about fishing boats, as a slight aside, fishing boats were often deliberately designed to roll, thus making it easier to haul pots on board in the days before powered winches, and the boat was "self jigging". So why do people think fishing boats must make good sailing boats?

    Catamarans can have some unique rigs, the bimast one being obvious. But from what I have heard tacking them can be a problem. Certainly they are not very practical, on a reach one sail will be over the deck, making life on board difficult never mind obstructing the helmsman's vision, while the other rig is hanging over the side, completely inaccessible (even worse than on a monohull). Remember, one of the great safety advantages of a conventional rigged multihull is that the boom and sails are always inboard.

    If a bimast rig, or a crab claw really was "better" (in every sense, ie handling, cost, efficiency) don't you think you'd see more of them around?? Unless you have money to burn, or are trying ideas on model yachts, it really is sensible to stick to conventional ideas.

    Sorry to sound so negative.

    BTW, Peter Spronk built many large lapstrake cats in the 1970's. - including the worlds longest cat at the time. Like all such boats they are noisy underway.

    Richard Woods at anchor on his Romany in the Bahamas
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