Stability Problems

Discussion in 'Stability' started by pierson, Sep 21, 2012.

  1. pierson
    Joined: Sep 2012
    Posts: 16
    Likes: 1, Points: 0, Legacy Rep: 11
    Location: Rosario

    pierson pierson

    Hello,

    my apologies, my English is very poor

    Im from argentina,

    I need your help

    Last year, I bought a new 1500 quicksilver with a evinrude etec 60 hp.

    Size,length 4,60 mts . width 1,83 mts.

    The problem is, the stability, my boat is tilted sideways, left or right.

    have raised the engine 3 cm above the V, The position is correct

    if the engine is placed below, the defect is most noticeable.

    the boat is heeling, both to the right and the left

    brought the boat to the dealer, he told me that the boat sails well.

    I need to find some solution to this problem.

    What effect would the hydrofoils?

    the problem disappears when navigating from 5300 to 6000 rpm.

    the problem is very noticeable, sailing from 3800 rpm to 4900 rpm.

    I send some videos.

    http://www.youtube.com/watch?v=OlO3i3rPhXM

    http://www.youtube.com/watch?v=gGlDTxSxjEU

    http://www.youtube.com/watch?v=H2a1hqUzGY4

    http://www.youtube.com/watch?v=Gu0_FuBceOU


    http://www.youtube.com/watch?v=OlO3i3rPhXM

    http://www.youtube.com/watch?v=gGlDTxSxjEU

    http://www.youtube.com/watch?v=H2a1hqUzGY4

    http://www.youtube.com/watch?v=Gu0_FuBceOU

    Thanks!!!
     

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    1 person likes this.
  2. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    Es un problema inherente en el diseño. Los ¨trim tabs¨ sirven para corregir el defecto. Tienen dos efectos, uno es de alargar la linea de agua y cambiar la locaión del centro de gravedad. El otro es que porque son ajustables, se puede cambiar la proporción de presion o levante dinámico de boarda a borda.
     
  3. pierson
    Joined: Sep 2012
    Posts: 16
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    Location: Rosario

    pierson pierson

    Excelente y muchas gracias,

    La ultima pregunta ,
    Colocar hydrofoil en el motor no soluciona el problema ? O solo colocando las trim tabs,
    De ser asi , que hydrofil me recomendarias ? Y si no sirven que trim tabs me recomendarias para colocar ?
    Muchas gracias
     
  4. Petros
    Joined: Oct 2007
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    Location: Arlington, WA-USA

    Petros Senior Member

    your English is just fine Pierson. Have you contacted other owners of the same design hull? looks to me like the hull was designed to ride lower in the water, more displacement is needed. You might try adding ballast, put some sand bags as low as possible (below the floor boards) at the center line about half way back from the bow. try 300 lbs.

    If that helps try some experiments, add a few more, take some away, move it forward and aft until the problem goes away or is minimal.

    If it helps, you can add or subtract the ballast depending on how the boat is loaded, leave it when you have light loads, take some out when you have more cargo/passengers/beer. The more beer you bring the less ballast you will need.

    if that does not work you might consider trailing edge flaps/trim tabs, the adjustable type. they attach low on the transom, at the water line, one on either side of the engine. they are adjustable. these are usually used to keep the nose down when underway, but it may help keep the boat centered on a even keel.

    looking at the pictures it appears the design of the hull has too much column below water line forward, it should have less "forefoot" displacement. And perhaps a less deep "V". But short of a hull redesign, it appears to me that when underway it rides up too high so it only rides on the narrow "V" part of the hull. Either having it ride deeper (more weight) or adding trim tabs at the outside edges of the transom will keep it centered better.

    You might also contact the manufacture and express your displeasure with the hull's behavior, this is not acceptable. the Dealer should do that for you, not much they can do about it without factory assistance, so keep after them as well. Or contact the manufacturer through the dealer, talk to the sales rep, you should be able to eventually talk to the hull designer who hopefully knows what it needs. Perhaps not if they are equally incompetent, but the designer may know of a simple fix if you are lucky.

    Good luck.
     
  5. pierson
    Joined: Sep 2012
    Posts: 16
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    Location: Rosario

    pierson pierson

    Thanks,

    I'm really worried, at this time the boat is in the factory,

    Today I was notified that take my boat from the factory , because according to them, are no anomaly.

    but I am very unhappy, and worried

    the name of the factory is marinesur, they have ISO 9001 - 2000.

    I can not believe the bad luck I had, trusted them because they are the best,

    there is nothing I can do.

    i Send to you, the answer of the manufacturer:

    Pier:

    Hemos analizado los videos que nos pasaste con el tecnico, y no encontramos ninguna anomalidad, por mas que se nota que cuando alguien se acerca a las bandas la lancha tambien se mueve.

    La lancha no tiene ningun vicio y se comporta dentro de los parametros para este modelo.

    Toda embarcacion en desplazamiento cambia de posicion si se cambian sus pesos interiores.



    In your opinion, hydrofoils are good for this case? o just de trim tabs,

    I ask this because the hydrofoils are easy to install and cheaper than the trim tabs
     
  6. pierson
    Joined: Sep 2012
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    Location: Rosario

    pierson pierson

    I forgot answer to you Petros, the boats of the same model have the same problem, not drive another,
    But I heard the same thing happens.
    Yesterday i speak whit the hull designer, he toll to me , the boat is fine, dont have any problem, he test my boat .

    try to discuss it, but fails to reach agreement
     
  7. Petros
    Joined: Oct 2007
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    Location: Arlington, WA-USA

    Petros Senior Member

    I am not familiar with the hydrofoil configuration, so I would not know if it works. the trim tabs will almost certainly work. I find it hard to beleive the manufacturer thinks this is okay, they do not appear to care about their customers. the hull is poorly design, or you are using it too light for their intended pay load perhaps.

    You might offer to the designer (and the dealer) that you will put your problem on the internet, and their careless response to you, and let everyone one know what poor service they give their customers, until they fix it. Rope two ugly steel drums to each side of your boat, take pictures and put on the web site, as a way to fix the crappy ride of your new boat. They will not be happy about that.
     
  8. pierson
    Joined: Sep 2012
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    Location: Rosario

    pierson pierson

    Welcome to Argentina,

    in a serious country, not something like that happen.
    here there is someone, who controls this manufacturer only NAVAL ARGENTINA prefecture.
    I am sure the boat was approved without verify.
    the problem of publishing on the Internet, then nobody will buy the boat,
    I told the factory that would do this, but did not care.
     
  9. pierson
    Joined: Sep 2012
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    Location: Rosario

    pierson pierson

    Thanks Petros...
     
  10. Petros
    Joined: Oct 2007
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    Location: Arlington, WA-USA

    Petros Senior Member

    I doubt a complaint to Naval Argentina would help either, they are only concerned with safety, and collecting their fee. It does not sound like this is a safety issue, just unpleasant. But you might contact them to see if their is anything they can do, but I would not put any hope in a government agency.

    If you can harm the sales of their boat, they will care. THey likely do not think you can have any affect on them. You can if you make it a "hobby" to let everyone know they do not care about their customers, parade your "fixed" barrel boat hull around in front of the boat dealer with a sign saying "this is the only way to use the poor boats they sell here". You will not get them to do anything unless you go to the trouble of making their life unhappy. Might be easier to fix it yourself, but it could be fun to take them on just for "sport".
     
  11. Petros
    Joined: Oct 2007
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    Location: Arlington, WA-USA

    Petros Senior Member

    BTW, you can make your own trim tabs for likely less than buying them, if you are handy with tools. Not difficult, just copy what you can buy with local supplers, simplify and be creative (make it strong enough, and adjustable).

    Than you can offer to do the same custom mod to eveyone that buys the same boat for some side income. You can even offer to do on the new boats for the dealer!
     
  12. pierson
    Joined: Sep 2012
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    Location: Rosario

    pierson pierson

    jajajaj thanks you.

    I'll consider.

    at least they'll remember.

    Thanks you , really thanks you.
     
  13. pierson
    Joined: Sep 2012
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    Location: Rosario

    pierson pierson

    When i finish the work.

    I will send to you, a picture of the work!

    Thanks
     
  14. gonzo
    Joined: Aug 2002
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    Location: Milwaukee, WI

    gonzo Senior Member

    I think that you are referring as hydrofoil to one of those tails or foils attached to the anti-ventilation plate in the outboard. Trim tabs are the two flat plates that can go up and down to adjust lift.
     

  15. Mr Efficiency
    Joined: Oct 2010
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    Location: Australia

    Mr Efficiency Senior Member

    This is a bit of a puzzle. The videos were on flat water with little wind, so that simplifies matters somewhat. Are we saying that the boats leans one way or the other with little or no movement in weight, from side to side ? Or is it caused by the camera operator moving around in the boat ? If it is a relatively lightweight boat, and the fact it runs freely with 4 people on board and just 60hp suggests it is no heavyweight, it could just be it has a little more "vee" than desirable, and someone standing up and bracing themselves using the windsreen frame could be enough to upset the balance. It is a small vessel and Mr Cameraman might be a bit larger than normal.
     
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