Swain BS_36 Stability curve

Discussion in 'Stability' started by junk2lee, Mar 9, 2011.

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  1. Dean Smith

    Dean Smith Previous Member

    I would look at boats that comply EU Recreational standards for class A. They make a lot of sense
    It is my understanding that USA was never interested in compliance this way
    Anything sold commercially in Eu must have that stabilty curve. I f I were buying a boat I would not buy unless that vessel did comply and that I was sure that the compliance had come from a reputable source. because yes you can comply a boat in say Poland for a few bottles of best Russian Vodka, or Bg or any other Eastern Eu country
    I submitted dwgs to an entity in UK . It was not so difficult
     
  2. Ad Hoc
    Joined: Oct 2008
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    Ad Hoc Naval Architect

    Exactly.

    Since you have reemphasised the point made earlier which appears to have gone over the heads of many. Highlighted again for those missing it..

    If you want to design from scratch with no understanding of what you’re doing and whether it’ll pass any of the minimum accepted standards around the world nor build the design in a manner that does not conform to any acceptable build quality standards, that’s fine; what ever makes you happy. When you try to obtain insurance, I’m sure they shall have a few things to say to you about it…but that is another matter.

    But you’re not… as again, Wynand pointed out:

    You may be an amateur in the build sense, home build whatever one wishes to define or call this. But, the design you have paid money for must be shown to be in compliance with ‘some’ standards from ‘some’ where.

    When you as an amateur sell your home made design to anyone, it is no longer an amateur design regardless of your competence in design/build.

    Just for clarity:

    Amateur
    “One who practices a thing only as a pastime, esp unpaid, opps. Professional.”*

    Professional
    “Of, belonging to, connected with, a profession…performing for monetary reward..”*

    *Source OED.
     
  3. abcdefg
    Joined: Mar 2011
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    abcdefg Junior Member

    Tad,

    The CE system in the EU is one that I am a fan of as does give reassurance to the buying public that what they are buying is of reasonable quality and standard. I am also a fan or more stringent rules and regs for commercial vessel like well all see around the world.

    It should also be said that conformance to any standard (whether structural, systems, stability etc) does not guarantee safety.


    That said, the BS designs do not fit into this either of the above broad categories. They are sold cheaply to people looking to hit the water in their own self built creation just like many other cheap plan sets that are sold around the world many of which will have been developed by persons with no interest in abiding by any standard. At the end of the day, why should I care if this is so. If someone wants to go ahead and build their own boat, fit it out using adapted/second hand gear then why should I worry that they might be putting themselves at risk. Just don't expect me to come on board or pay for the privilege of doing so. In australia, I can go to sea by myself in my own sailing boat (even pro built) as long as I have the necessary safety gear such as lifejacklets/epirbs/radios etc. There are many yachts and sailboats around under this system, many of which would not meet ISO 12217 or any number of other stability standards and yet there is no epidemic of drowned sailors occuring.



    It is commendable that you have attempted to put a bunch of dubious data into a model and run a GZ curve, but all you have proved is that the designers claims of 175 deg positive stability are almost certainly fabrications. It may not meet ISO and may be tender, but at the same time won't turn turtle as soon as you take off the mooring lines.


    Looking forward to curves from you without the "preliminary" tag.
     
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  4. pdwiley
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    pdwiley Senior Member

    Note that I didn't take any issue with the information you provided, nor make any attack on you for its paucity. I do understand peoples' desire to keep some anonymity. I don't put a great deal of weight in what you say simply because you don't have a long track record here or outside verification of what you claim about yourself. People reveal a great deal about themselves over time so a lot of posts tend to reveal character & knowledge to a degree. If you keep posting here then your posts will tell more. Everyone is a newbie at some point, it goes with the territory. Does it really matter? Well, probably not unless you take a stand contrary to the prevailing one and then can't support it with evidence.

    I point to Jack Hickson as an example.

    PDW

    PDW
     
  5. pdwiley
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    pdwiley Senior Member

    Well said. I agree 100%. My only caveat being that I would not permit the ownership of EPIRBs to people who do not have insurance, nor would I allow SAR operations for them if they go missing.

    Note that I wouldn't stop them building boats that nobody would insure and nor would I stop them going blue water sailing. As long as the taxpayer doesn't have to pay to rescue them, I don't mind if they are prepared to risk their lives to a degree greater than they would in a vessel of different design. The nanny state has already gone too far. Bill Tilman and John Guzzwell, to name 2, would never be permitted to leave port nowadays.

    This is where I'm coming from WRT the BS design. If everyone knows what the numerical analysis says and builds one anyway, fine. I simply object to Brent and others either avoiding the provision of analysable data or posting outright fabrications - see post 1 in this thread from junk2lee for a classic example.

    PDW
     
  6. Wynand N
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    Wynand N Retired Steelboatbuilder

    Gentleman,

    I cannot recall one instant in this post or the other two notorious threads "Origami and Transverse frame" where any member had said that the BS origami boats are crap....
    What was said in the past is that the strength of this design is in serious doubt and some construction photos posted were outright unacceptable and affirmative to the fact. At the same time BS condemned any suggestions made to improve scantling and make it structurally more sound.
    In fact, MikeJohns, a Qualified Engineer for one and respected on this forum offered (more than once) to do a structural analysis for FREE of charge to help BS get his boats more structural safe and the rudeness and insults MikeJohns had to endure from BS because of this was frightening to say the least
    I believe this should have been a turning point for BS to be able to market his designs with a structural analysis by a structural engineer to prove its safe (provided weak points were addressed in the design) But then again, a fool is born every minute and we still have to listen to BS/Jack trying to tell the world his boats are safe.....

    As for this thread - we all had a laugh about the fabled 175 degree positive righting moment issue in the recent past, and yet it raised its head here again, albeit by one of BS cronies - heck, this guy just do not give up:confused:

    Now that TAD had crunched some numbers, although on data received and not actual lines, I would say is is quite an accurate assessment of the boat's righting ability. Any other small changes and alterations to the input would not really make a worthwhile change to the current results and please, lets bury this issue. Surely it will pop up again in a years time or so - no, I do not have a working crystal ball, but BS past history dictates his future actions:rolleyes:

    Any boat designer worth his salt will produce a stability curve on request with numbers and have this as a std issue on the lines plan.
    Note of interest: Dudley Dix have stability curves of each of his designs on his webpage for the world to see - now that would inspire confidence with the buying public.
     
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  7. Dean Smith

    Dean Smith Previous Member

    Well said. I agree 100%. My only caveat being that I would not permit the ownership of EPIRBs to people who do not have insurance, nor would I allow SAR operations for them if they go missing.
    From pd wileyt
    that is just plain daft, we all have the right to use a boat
    the days of JPMORGAN, who coined the phrase"if you have to ask the cost, then you should not be boating" have gone
    the masses enjoy the sea
    The fact that Aussies sue as a nation of people more than any other, keeps many in fear so that they cannot boat.
    Sueing pushes up premiums Sure third party is a must but to make insurance compulsory is a nonsense, but now law in QLD for vessels over 15m, the argument being, "it cost to clean up wreck pollution"
    stuff rules i am for one sick of em
    i build boats that complied before the term compliance was invented, have no argument about that
    But let people be free
    thank God that here boat reg is not reqd unless you go foreign,they people screamed NON NO and that was that
    In Au the insidious tenticles of officialdoms red tape are everywhere an d you know what? you bloody deserve it for your apathy
    you are the most litigeous nation on earth Official!!!
     
  8. pdwiley
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    pdwiley Senior Member

    Dean, why don't you go back and actually READ what I wrote? I thought it was pretty clear.

    To recapitulate: You don't have to have insurance but you also don't have the right to expect others to look for you if you screw up! If you want to go to sea, fine, do so, just take the responsibility for the outcome yourself.

    Where did I even mention anything about suing anyone? That's a complete figment of your imagination.

    As for rules & regs in Australia, when I compare ours to NZ funnily enough you guys don't come off too well. I'm pretty sure I can go foreign with far less in the way of equipment & paperwork/experience than you can.

    PDW
     
  9. Dean Smith

    Dean Smith Previous Member

    yes but you try coming INTO Au as a foreign flag, they hound you to death, trot on down to your marina and speak to the cruisers in Qld
    Sure we have Cat 1 for foreign and thats a good idea? Liferaft, ssb, epirb, inspect hull rig rudder the works so fools have a mediocre of a chance Good Morning to you:)) keeps you on your toes
    i remember my first boat and trip offshore, they asked could I nav, yes I could sorta, using moon 10 days a month and sun only the rest we survived. One thing abt sextant nav, chances of anyone being on a recipricol course are low as one zig zahs far from the Rhumbline
    We hit bricks in uncharted seas in Fiji. We had a steel ship, not Origami!! that I built in 70,s. One other thing, I would not go Ocean Cruising in a plastic, ferro or origami:)
     
  10. Jack Hickson
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    Jack Hickson New Member

    The stability curves are posted on the origamiboats site. Interesting, that boats which have three dozen fragile plastic thru hulls, which can easily be kicked of with a light kick , boats which capsize at around 120 degrees, are ISO approved ,yet boats with welded in stainless thru hulls, and which have, according to Tad, a much higher AVS , are condemned. It appears to be a case of building "DOWN" to a standard rather than building up to one. It wouldn't appear wise to go to sea in a boat designed and built "Down" to such a standard.
    Mike Johns was the guy who said that a boat which had cruised for over 3 decades, with no structural problems of any kind , just may have structural problems in the first four hours. Does this somewhat undermine the credibility of his claims and calculations? It is clear that numbers can be shuffled to say whatever you want them to say, and any numbers he came up with could be juggled to say whatever he wanted them to say.
    As ABS rules say, a boat with previous well proven ,satisfactory track record is as good as any predicted performance. You would be hard pressed to find any stock design with the flawless, trouble free, offshore track record of the BS 36
     
  11. Dean Smith

    Dean Smith Previous Member

    fact is that most cruisers encounter knock down conditions once in a lifetime, if at all
    I do not care if you been circling the planet at low lats all your life you may never get into a gale Whereas if you sail in 46 South , you may likely get into full gale and more many times a year
    i do not believe this is Brent writing, the writing is too articulate and grammar is good.
     
  12. Jack Hickson
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    Jack Hickson New Member

    As beam so negatively affects AVS, high initial stability often comes at the expense of ultimate stability. So when "A bit tender" comes as a result of moderate beam , it may indicate a plus, when it comes to ultimate stability. ,
    So in this case, ISO approval may be a negative, in terms of AVS
     
  13. CT 249
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    CT 249 Senior Member

    1 - On what basis do you claim that Australians sue more than any other nation?

    Here's a hint - Google "most litigious nation" and you won't come up with Australian examples.

    And who in the world makes such a title "official" anyway?

    2 - On what basis do you claim that "many" people are in such fear of litigation that they don't "boat"??? I've never heard that or seen a shred of evidence for it.

    I've got third-party insurance to protect me from litigation - it costs about $7 per week for a 28 foot yacht. My third-party for my windsurfers costs me 26 cents per week.

    If $7 per week is going to stop you from going out on a boat you'd have to be on a very tight budget.

    If you are going to slag off an entire country, you could at least get some facts right.
     
  14. MikeJohns
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    MikeJohns Senior Member

    Yes Deja vu thanks for the PM......wow this thread certainly moved on shame it didn't stick to stability.

    Brent does this in lieu of valid argument. Sad but he's his own worst enemy, you can watch him demolish his platform, sink from sight only to rise from the ashes a year or so later to do it all over with the same self defeating facts and arguments.

    The link goes directly to one relevant post, I got a little testy after Brent had dished up some of his 'facts' for the third time or so being corrected each time and not listening.

    [http://www.boatdesign.net/forums/metal-boat-building/origami-steel-yacht-construction-248-40.html#post386494]

    And facts can be distorted and lies can be created and used for marketing for financial gain :rolleyes:
    Some effort went into other threads that clearly demonstrated that the Canadian origami cottage industry claims were very misleading even to the extent that many would consider fraudulent.

    Brent Swain also showed himself to be a pathological distorter of facts on several other threads so no surprise here.
     

  15. pdwiley
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    pdwiley Senior Member

    Bit difficult seeing I live south of Hobart.

    Let's not move to arguing about Customs & Immigration stuff please. I'm not interested. If you're unhappy with Australian procedures nobody is forcing you to sail over here.

    PDW
     
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