Swain BS_36 Stability curve

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

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  1. pdwiley
    Joined: Jun 2008
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    pdwiley Senior Member

    Same old same old, Mike.

    Why have you let the rain put you off getting wet under a dripping hull?

    PDW
     
  2. Wynand N
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    Wynand N Retired Steelboatbuilder

    Amen....

    And believe it or not, I had been neg on reputation by some nameless individual and this was the message/reason; "You disregard the proven"
    I have a good idea whom it may be but he can rest assure that I will not retaliate with such pity - I only neg insulting and rude behavior when called for which is a rare event....

    Now my question to this person; what was proven on this topic and what did I disregarded:?:
    Very seldom have I neg someones reputation over the years, but at least I had the balls to put my name to it. Now do you have what it takes to comment on your statement in a post?
     
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  3. Dean Smith

    Dean Smith Previous Member

    Mike, was not the stability done to DEFF. How many years have you been getting your **** in a tangl;e with BS? Lighten up all of you.
    PD I am an Aussie
    Old saying believe half of what you see and nothing of what you hear
    A wise ole owl sat in a tree
    the less he said the more he see
    the more he see the less he said
    What a wise ole owl was he
    So in you retirement , get off here, go catch a fish or a cold or whatever
    smile and dee world smiles wiv you mate
     
  4. pdwiley
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    pdwiley Senior Member

    I'm not annoyed, Dean. Just don't feel like discussing Customs etc here.

    Been running an angle grinder most of the afternoon, a nice drink seems about right now.

    I still think the origami concept has a lot going for it provided you are happy with the restricted range of hull shapes. If the BS 36 is on the tender side, it's not the only one out there. I recall George Buehler saying a number of his designs were tender.

    PDW
     
  5. MikeJohns
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    MikeJohns Senior Member


    Well the stability still requires an experimental confirmation of kG aka an inclining test. It also merits some discussion of sealed masts and their real potential contribution to the RM curve wrt inversion.

    I could have asked Jeff to delete the post since it's slander, but it's better to leave them standing for others to see the measure of the man.

    Remember the old adage?, If you want to get the attention of an ornery old bull you hit him with a 2 by 4 somewhere tender, nothing else gets noticed. Slowly and painfully we all learned that about Brent.

    You only get facts through to BS in an exchange just short of violence, bit by bit he's dropped his most bizarre beliefs because of these exchanges. That can only lead to the common good IMHO.
     
  6. Jack Hickson
    Joined: Jan 2011
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    Jack Hickson New Member

    Said the livery stable owner to Henry Ford.
    Said the livery stable owner to the Wright brothers.
    Said the scribes to Guttenburg.
    Said the telegraph operator to Alexander Graham Bell.

    I can imagine a stone age conversation going something like this :" Why Trog invent wheel? That not proper way. Do it proper way. Drag it. That how it's done . Wheel not how it's done . Tell Trog, "Don't be so lazy." Trog lazy bum."

    History repeats itself.
     
  7. HReeve
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    HReeve Junior Member

    Still waiting for that Rule citation...
     
  8. Jack Hickson
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    Jack Hickson New Member

    ABS Rules for Offshore Yachts
    1.5.2
    The committee is at all times ready to consider alternatives and scantlings which can be shown through "EITHER SATISFACTORY SERVICE EXPERIENCE'"or a systematic analysis, based on sound engineering principles, to meet the overall safety and strength standards of the guide.
    Done!

    It appears that the static stability tests advocated by Tad and Wynand , such as timing roll period, have nothing to do with self righting ability, but deal only with static stability. This can be enhanced by excessive beam, and flush decks , which are responsible for problems with reduced AVS and self righting ability, as was pointed out by Angus Primrose and Tony Marchage.
    Thus sticking to ISO rules actually encourages boats with self righting problems, and could lead one to a boat which is anything but adequately self righting.
    Excessive beam also negatively affects directional stability and downwind control. Narrower boats are for more directionally stable, and easier to control downwind.
    The changes in Tads stability curves, as the factors affecting it are pointed out to him, demonstrate clearly ,how a factor can change the results drastically . I've seen curves for another design, which show the cabin and wheelhouse buoyancy change the AVS by over 40 degrees. Begs the question "What other factors have been left out?"
     
  9. HReeve
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    HReeve Junior Member

    I stand corrected.
     
  10. Ad Hoc
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    Ad Hoc Naval Architect

    HReeve

    This statement is in all Classificiation Society rules.

    What you really need, is the formal Class approved letter dated and stamped showing that said boats satisfies this rule.
     
  11. Tad
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    Tad Boat Designer

    Please cite any place I have ever advocated roll timing, I never have because I don't consider roll timing worth the effort......Roll timing is inaccurate due to the use of a fudge factor (rather than a real measurement) in the GM height equation..........

    To go back to the beginning and re-cite because you apparently don't understand......... the static curve of righting arms is a universally accepted representation of the "righting force" exhibited by a particular vessel at various heel angles up to and including 180 degrees (capsized) ......Thus the static curves of righting arms of your design which I have produced and published do indeed have something to do with the subject vessel's "self righting ability".
     
  12. Tad
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    Tad Boat Designer

    Jack....

    Waving one rule around while poking at another seems a bit odd......

    The ABS stuff has nothing to do with stability........and nothing has been "shown","based on sound engineering principals"........Do you seriously believe you can walk into ABS and tell them "there are hundreds sailing" and "They haven't broke yet"....and your statements will be accepted and your design will be classed by ABS? Never mind they haven't dealt with vessels under 79' in many years and the boilerplate you are citing is in "OFFSHORE RACING YACHTS", which has some problems to begin with and was last published 17 years ago..........
     
  13. Wynand N
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    Wynand N Retired Steelboatbuilder

    Typical BS rant and ********:rolleyes: cant wait for the humble bee to put in an appearance again..

    This is not BS aka JH proven style or vocabulary ability as proven in the past. Neither his ability to use technical terms, explanation etc.
    Seems like he has a ghostwriter with a little boat know-how posting on his behalf.....
    Recently someone also made a similar remark at a post not believing is BS/JH rant.
     
  14. junk2lee
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    junk2lee Junior Member

    Welcome to the thread,abcdefg.
    I'd give you some "Rep" points,but of course,I can't!
    you see how it goes here...:)

    otherwise,
    off on tangents again,are we?
    redherring.JPG
    it still looks like a pretty standard boat,to me.
     

  15. Jack Hickson
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    Jack Hickson New Member

    Go talk to Don in Nanaimo, who pounded across three hundred yards of Fijian coral reef in his BS 36 Viski, with minimal damage, or read his book on the trip, or talk to his crew. You haven't stated what you would consider proof, as you continue to call those with real experience in extreme conditions with these boats ( which none of their critics have) :"liars."
    You claim these boats don't pass ABS rules, and when your error is pointed out, you claim ABS is irrelevant, contradicting your earlier claims.

    It appears that what was done with ISO, was to take initial stability calculations for power boats and try apply them to offshore sailing craft, which are a totally different ball of wax.
     
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