Transverse frame calculation

Discussion in 'Class Societies' started by DUCRUY Jacques, May 1, 2010.

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  1. Brent Swain
    Joined: Mar 2002
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    Brent Swain Member

    Some have full bulkheads some are a wide open layout. The difference in hull stiffness is unoticeable. They have no dependence on interior woodwork whatever. You can put a hydrailic jack from one chine to the hull deck joint on the opposite side and crank it to full externsion without deforming or changing the midship section in any measureable way. For that to happen the hull plate and the deck plate would have to stretch diagonally, at a tensile strength of 60,000 PSI.You will only stretch the plate locally where the jack meets it. This proves the redundancy of transverse support in small sailing craft.
    The Gringo wouldn't have looked much different after the collision, had she had no transverse frames.
    An origami hull is very floppy before you put the decks on . She would remain just as floppy no matter how many transverse frames you put in , until you put the decks on. Thus the treansverse frames are irrelevant in supporting the hull in this way.
    I understand it may be diffficult for many of you to comprehend the basic geometry until you have seen it . I suggest you further your understanding by tacking together a frameless sheet metal model , without the decks on. then put some frames in and see if it is any stronger, then tack some decks on and see the difference.The structural principles will only then become obvious to you. I have been doing this for 30 years on full sized hulls. None of you have , yet you are telling me that what I've seen with my own eyes over 30 years is false.What some of you are claiming I have seen disproved repeatedly , for 30 years.
     
  2. Steve W
    Joined: Jul 2004
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    Steve W Senior Member

    Brent, im not disagreeing with you, just pointing out that bulkheads and cabinetry are in fact transverse structural members that impart considerable stiffness like it or not. Most boats, regardless of material have full or partial bulkheads or partitions every 1 -2m or so just because accomodations work out that way,pretty much all glass boats have no transverse framing,just tabbed in bulkheads and furniture,like your hulls they are floppy until you add the furniture and decks.
    Steve.
     
  3. Brent Swain
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    Brent Swain Member

    Like origami boats , glass hulls use shape for stiffness. Why don't they have frames? Shape makes frames redundant. It also works for steel .
     
  4. dskira

    dskira Previous Member

    They have a lot of forum for people like you. You should try sharing fornication, perhaps you will have an epiphany.
    Now an explanation about my comment: I have to endure a man who is NOT a naval architect, he is NOT a boatbuilder (never built more the 38') and gave lesson of naval architecture and boat building to everybody.
    His arroguance and his ignorance in matter of boat in general is phenomenal.
    I was patient, even answered constructively with him, but he resist, taking his ignorance as a shield, having the delusion that ABS, VERITAS, LLOYD'S are wrong! How much sick you can be.
    Keep you putrefaction for yourself.
    Ori means folding, so fold your crap and disapear.
    Daniel
     
  5. Brent Swain
    Joined: Mar 2002
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    Brent Swain Member

    With the Gringo, transverse frames are structurally insignificant in limiting the damage, when compared to the huge I beam which is the combination of the side decks , on edge ,welded to topsides and bulwarks, as well as the cabinsides holding the side decks in line, as well as the bottom plate . There is no comparison between the structural support they give, and the relatively tiny transverse frames. It takes light years more pressure to crush a side deck or bottom plate on edge , when it is so well supported by surrounding plate, than to bend a realtively tiny flat bar on edge . Compared to the mass of a freighter hitting the hull , and the resistance of sidedecks on edge, and bottom plate almost on edge, transverse frames are as insignificant as mosquitoes on the topsides.
    I don't fit my interor tight against the hull. Its only bolted to a few tabs and has never broken loose or even worked loose, nor moved noticeably, and the hull has never flexed enough to touch it , in tens of thousaneds of sea miles, so it is definitley non structural.

    I think the Gringo pictures converted a lot of cruisers to steel, especialy those with families aboard. There would be a lot more steel boats out cruising if people were more aware of what punishment they will take . Gringo may have tipped that balance, for many.
     
  6. Brent Swain
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    Brent Swain Member

    What you are saying is sacred cows should never be questioned, in any way. We'd still be in the stone age if everyone had listened to ultra conservative preachers .
    You blow your credibility completely when you say that someone who has built 3 dozen very successful boats , over 30 years ,for very happy owners, after years of offshore miles under their keels , is not a boatbuilder, or someone who's boats have been out cruising for over 3 decades and who's very experienced offshore cruising owners have often built several of my designs , who's offspring are now building my designs, who's designs have survived the many torture tests that they have encountered over several decades , is not a designer. As Dudley Dix said elsewhere on this site, years of proven sucess in offshore cruising is conclusive proof of the design and concept , or words to that effect .
    People like you would have been the ones to tell Gutenburg "We hate your type" or tell Ben Franklin " Go fly a kite" or tell Columbus and Galileo" How dare you challenge what is common knowledge . Everyone knows the world is flat, and the centre of the universe. They surely can't all be wrong, and you right. How arrogant of you?"
    This site, and sites like it are here to discuss openly all the structural issues of boatbuilding , not to coddle and defend sacred cows, at the expense of progress. Ultra conservatives in any field are millstones around the neck of progress.
     
  7. LyndonJ
    Joined: May 2008
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    LyndonJ Senior Member

    Brent

    I think the real problem is that you extrapolate from experience with 30 foot vessels and make unfounded claims for vessels up to 60 feet without due basis of reasoning except that it works for small boats.

    Without a decent engineering basis and understanding you are like the medieval builders and their structures . They build bigger and bigger until they start to fail and then they go smaller again.

    The argument that the little church stood for hundreds of years so we can therefore build one 8 times the volume with the same structure safely. And get our meagre engineering reasoning wrong too.

    That unfortunately is your style of argument.

    Lots of buckling tests of real panels give us very hard data to go on. Non linear FEA is aligned with these results and is a very reliable accurate indicator.
    I really don't think that in your head you can see the failure modes of the structure, you are seduced with success of small vessels and think you can scale it. But on a larger vessel the frames are critical and that is easily shown if you don't believe it.

    So where is the boundary for transverseless designs? Probably a lot smaller than you reason.
     
  8. dskira

    dskira Previous Member

    I will use a metaphor.
    Brent goes to the dentist school.
    After two weeks of school he knows how to pull a tooth. Just one particular tooth.
    So he decide to go on himself as a dentist independent.
    He pull just the one tooth he knows how to pull.
    He decide that the school of dentistry is a bunch of nobody who knows nothing about dentistry. But Brent knows how to pull one tooth, so he decide that the real dentist is the one who know how to pull just this tooth and nothing else. He do not know what is a bridge or root canal. He doesn't care, dentist according to Brent, is just the one who pull one tooth.
    Some dentist try to tell him he should finish his school before pretending he is a dentist and learn how to be a dentist.
    He says that all dentist beside him are stupid and knows nothing. Since he know how to pull one teeth, it's enough.
    In a real world he will be prosecuted as a fake dentist.
    Is Brent a dentist? no of course.
    Is Brent a boabuilder? no of course.
    It is the reason why I said Brent lie when he say he is a boatbuilder.
    He knows one thing and very partially, without any technical background supporting is outrageous claims. And the worth, he doesn't know why is misnamed origami (which as nothing to do, origami is the art of folding paper, not conical forming as he does)
    He is working on a very narrow spectrum. He can't really explain it, so he make the example with the Tupperware cover.
    How low a so call designer builder can go?
    So Brent even the name of your system is wrong, I hopped you get this one (the most easier part) right.
    As for the rest, continue dreaming, but it is sad that you are trying to pretend to teach people your way of building.
    You should not do that, since you have not by far the knowledge and background to teach anything.

    Daniel
     
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  9. dskira

    dskira Previous Member

    Coming from you its quite ridiculous.
    You can't discuss, since you don't know how to share, learn and research. The basic tools to confront ideas who make us better.
    Please cool off on experience, you don't have any.
    Experience start with the brain, the accumulations of information we take and process to be better. You never did this processing, it is the reason why you are cornered as arrogant. It is your way to shield your ignorance, and worst, you absolute disgust for learning.
    Poor man.
    Daniel
     
  10. dskira

    dskira Previous Member

    Are you comparing yourself to all these great peoples?
    God syndrome?
    I knew you are slightly off, but at that level, no I will never thought.
    By the way you should learn what these great people did. You have the habit to put names on your posts, but not sure what they represent.
    Daniel
     
  11. Brent Swain
    Joined: Mar 2002
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    Location: British Columbia

    Brent Swain Member

    I'm one of the few designers who openly share experience on this and other sites, at no charge. I've shared everything I've learned over the years, freely, while others have suggested I guard it jealously as "Trade secrets". If I wanted to keep what I've learned I wouldn't have written my book. I certainly wouldn't be spending my time answering peoples technical questions for free.
    Your suggestion that someone who has built three dozen boats, has roughly 200 of my designs out cruising, has singlehanded across the Pacific 9 times and has cruised 11 months a year since the mid 70s, has no experience , blows your credibility completely.
    So tell us what your experience is.
    If I was closed to learning I'd be doing it the old fashioned way, worshiping Gurus and not questioning anything. I'd never have tried anything new, and would criticize anyone who does, like you.
    If you want to see that, look in a mirror.
     
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  12. dskira

    dskira Previous Member

    Why you put in same sentence: Guru and learning?
    Who ask you to worship? only yourself post over and over this concept.
    Strange.
    Been to Wako lately?

    We learn to be free. That is a difficult concept for you since you are in your own prison

    Daniel
     
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  13. Brent Swain
    Joined: Mar 2002
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    Location: British Columbia

    Brent Swain Member

    As I've pointed out , boats approaching 60 ft haven been very sucessful in extreme conditions, over many years, and tens of thousands of miles, in some of the roughest ocean conditions anywhere. . That proves they work, period. It's ludicrous to say that that which has worked so sucessfully over many years and tens of thousands of miles in such conditions "Won't work "
    Over around 60 feet, you do need frames, but there are far better ways of building a metal hull, than the grossly outdated method of imitation wooden boat building , developed for a material which has strength in one direction only, at a time whan that material was the only one useable.
    Once you have pulled the hull together and fully welded the seams, you can put whatever framing you want in, far more easily than the traditional frameup. This also results in a much fairer hull.
    Dskira, what you are saying is that only things that you agree with should be allowed to be stated here . I apologise for talking so far over your head ,or beyond your capabilty to understand , but I've had some very positive coments about my postings, here and elswhere on the subject. You are not the only student in the class.
    We learn to be free? Exactly, and having learned to be free of the long hours of setting up frames for a grossly outdated building method , free to launch my own boat one month after the steel arrived , and free to have a completely fair and attractive boat, without having to spend decades working to pay for, free fom having to give the bondo experts tens of thousands of dollars to make a boat look good, free from the worries in sailing at night in an unseaworthy boat, which couldn't withstand a collision with a container, log, rock etc, free to semi retire in my mid twenties , it is knowledge I want to share with others.
    When some one suggests only the slow , time consuming , extremely labour intensive , bondo addicted , years in debt, way, is the only way, you'r damn'd right I will speak up. Some will no doubt be suckered into the "Be reasonable and do it the hard way" school of thought, , but I will always offer them an option. There will always be enough people too intelligent to buy the elitist ********, enough to keep me as busy as I want to be.
    As for the gullible ? I wouldnt want to work for them anyway. I prefer intelligent company.
    Buy my book and read it before commenting on it's contents. It will save you a fortune, and a lot of needless work ..
     
  14. dskira

    dskira Previous Member

    No need to continue in this thread.
    I give up.
    Good night Brent, but I hope your night one day end and you will see the sun.
    Daniel
     

  15. apex1

    apex1 Guest

    And thats your only reason to contribute here!............. Buy my book

    STOP BEATING YOUR DRUM HERE BRENT!

    Almost all of the serious members have begged you to stop your dumb claims and senseless drivel about structures you do┬┤nt comprehend!

    GET IT!!!
     
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