Swain BS_36 Stability curve

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

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  1. Jack Hickson
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    Jack Hickson New Member

    One can be fresh out of design school,with all the required paper to claim to be a fully qualified designer, without having ever set foot on a boat. His qualifications couldn't hold a candle to anyone who had extensive offshore cruising and decades of building experience. He would be nowhere near as qualified in real terms, as someone with many highly successful boats to his credit, which have been offshore cruising for decades, nor any designer who does product testing year round for decades. I don't know many designers who do that. Too many get their expereince at the drawing board only.
    There are enough of these boats around, that most can go for a sail in one, or talk to people who have cruised extensively in one, rather than get their advice from people who have never set foot on one, let alone sailed anywhere in one. You can even sail in 20 knots of wind, and find the rail is nowhere near the water , rather than rely on uninformed speculation .
    I know one couple who sailed back to BC from Rarotonga in their Saugeen Witch . They said the side deck and cabin side were submerged most of the way, and their kids saw mostly green water through the cabinside ports.
     
  2. Jack Hickson
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    Jack Hickson New Member

    #1 has been posted nmany times. Junklee has posted #2 in post one of this debate..
     
  3. Jack Hickson
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    Jack Hickson New Member

    Promoting hatred against an identifiable minority, is a serious criminal ofence in Canada, with serious jail time as a consequence.
     
  4. Jack Hickson
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    Jack Hickson New Member

    With all that Tsunami debris floating over from Japan I wouldn't want to be out here on a dark stormy night in a cal.
    Maybe a demolition derby with a BS boat would settle the structural matter quickly.
     
  5. Jack Hickson
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    Jack Hickson New Member

    You could make the chine 3/4 inch thick at that point, with no major effect on sailing efficiency, but a huge increase in reef protection. . Fiberglass boats could have it several inches thick, with no negative effect on sailing performance.
     
  6. TeddyDiver
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    TeddyDiver Gollywobbler

    Dejavu... or a time warp? Anyone else hear that ridiculous mantra again?

    culous mantra again?

    mantra again?

    huge strength!

    huge increase!

    :p
     
  7. welder/fitter
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    welder/fitter Senior Member

    Yeah, but the information I've read is on the origamiboats site, where owners of these boats are discussing this and on at least one blog of a BS owner. No time to put up links right now, but I've archived a lot of this info., so when I get a chance I'll put the exact quotes & by who.
     
  8. welder/fitter
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    welder/fitter Senior Member

    LOL no, no demolition derby, but I'd be willing to race you from the West Coast to Hawaii. From Hawaii I head south, so won't see the worst crap. I wouldn't be able to wait for you to arrive in Hawaii, however, as that'd take too many days out of my schedule & who knows if you'd ever make it all the way in that boat of yours. But, if you have the nerve...
     
  9. bntii
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    bntii Senior Member

    Your experience hopefully makes you a better designer than you would have been in its absence. It provides no indication of how your design abilities might compare with others.
     
  10. Ad Hoc
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    Ad Hoc Naval Architect

    Oh how quickly you forget your own mantra.

    #1….no inclining report has ever been submitted on this forum, nor this thread by you/junklee, regarding the BS36; all just theoretical nonsensical guess work, not real actual facts as required and requested many many times.
    #2….no GZ curve has been shown nor submitted on the forum nor this thread by you/junklee that shows any compliance with any rule anywhere.

    And while you’re at it, please provide the ABS approved letter of compliance of satisfying their structure rules, again, as you have claimed many times.
     
  11. Ad Hoc
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    Ad Hoc Naval Architect

    See, that is again, where you keep going wrong, and the whole purpose of this, and other threads related to your designs.

    A young gradate with such qualifications would be educated in professionalism and risk and how to mitigate such risk, professionally. A graduate, indeed any professional engineer, would have to follow professional guidelines such as these:
    http://www.engc.org.uk/risk

    No.3 is most pertinent:

    3. Comply with legislation and codes, but be prepared to seek further improvements
    Regulations and codes are generic. They can only deal with anticipated events, and cannot predict every possible situation. Engineers should take a measured, yet challenging approach to potential risks, whether or not regulations apply. Engineers should:

    • act in accordance with codes of conduct
    • know about and comply with the law in countries where they are operating or where their products will be used
    • recognise and understand the intent behind standards and codes, and understand when their limits are being approached
    • comply with current relevant legal requirements governing engineering risk issues
    • seek advice where necessary
    • where it is reasonably practicable, seek further improvements, thus embedding a culture of seeking continuous improvement
    • be open minded and avoid hiding behind regulations


    Whether said graduate knows what he is doing or not, s/he would understand risk. Thus if they cannot prove and satisfy themselves and demonstrate the level of risk and compliance to an independent "person" or client, they seek advice from others.

    Oh, I won’t even go to No.4, that’s off the scale!
     
  12. pdwiley
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    pdwiley Senior Member

    My chine already is 20mm thick, it's a 20mm solid round bar. Adding say a 6x50 strip at the bisected angle would stiffen it dramatically. You never have understood the proper use of steel and location. Your continued use and advocacy of angle iron longs on your designs is a classic example.

    As for your comments re the Saugeen Witch, even if true it tells us nothing unless you also post the full details of build and rig, plus cargo carried. OTOH you and others can check out Bernie Harberts account of his circumnavigation in a Witch any time. He has quite a few photos and a pretty detailed account.

    I recall Tom telling me that some idiot put a sloop rig on a Gazelle hull once. Had to reef down in 15 knots. Is that a fault of the hull or the owner who ignored the designer's advice?

    There have been more Witches built than BS 36 hulls and probably 10 times more Gazelles built. That's just 2 out of some 250+ designs.

    PDW
     
  13. Jack Hickson
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    Jack Hickson New Member

    Put an impact next to the round bar , from a sharp rock, and the round will increase the likelihood of a hole being punched through the 3mm plate. Put diagonal reinforcement, as you have suggested, and it will do nothing to reduce the odds of denting her or holing her at the chine. You may even increase the odds where it joins the bottom plate. Put heavier plate on the flat, and you drastically reduce the odds of such a problem.
    One BS 36, the Avro, spent a night on the rocks in a 35 to 40 knot wind, with about 70 miles of fetch. No damage other than chipped paint. The owner attributed that to the doubler plate on the chines.
    Most Canadians have a high resistance to any foreign organization appointing themselves our boss.
    Was Bernie the only one to circumnavigate in a Witch? That makes one..
     
  14. HReeve
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    HReeve Junior Member

    And one can sell books of boat plans without a demonstrated understanding of the importance of a proper inclining experiment in assessing the stability of a vessel.
     

  15. Jack Hickson
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    Jack Hickson New Member

    Right on! 40 years experience is far more reliable than any calculations.
    Haidans boat is a twin keeler, Junklee's post was referring to a single keel BS 36
    The AVS of the twin keeler is slightly less, but far better than the Farr 38. All builders know that, but are happy, given the advantages of twin keels.
    Check post 296 again. It answers questions that you guys keep asking.
     
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