Smooth transition hull and bulb

Discussion in 'Software' started by deanlife, Apr 29, 2015.

  1. deanlife
    Joined: Sep 2012
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    deanlife Junior Member

    Hi, I'm trying to make a smooth transition between hull and a simple bulb form that I have done by lofting some sections.
    But I cant do it, I ve tried all kinds of tools that I ve know, no luck so far.
    Any ideas?
     

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  2. DCockey
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    DCockey Senior Member

  3. bhnautika
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    bhnautika Senior Member

  4. bhnautika
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    bhnautika Senior Member

    Here is an example
     

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  5. DavidJ
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    DavidJ Senior Member

    I often like to go back to curves. I find it easier to get clean surfaces if I start with clean curves rather than using all of the fancy automated tools. It also produces what I want instead of what the software thinks I want. You get more control over radiuses and locations of knuckles.

    I'd take some sections through your surfaces and then fair the bulb and the hull curves together into single continuous sections. Then you can rebuild the entire hull using the new curves and your bulb surface will be integral to the hull surface.
     
  6. TANSL
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    TANSL Senior Member

    This is very nice, lovely I would say, but in practice it is completely unrealistic. Such plates cost more work than the rest of the ship.
    From a construction point of view I do not see much downside to the fact the bulbous inserteb directly into the hull, no smooth transition.
     

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  7. DavidJ
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    DavidJ Senior Member

    Yes, Tansl it could be very difficult to build something like that. However, that's assuming steel (or similar) construction. If it's a composite vessel you can build the mould to have any shape you want and a bulb faired beautifully and seamlessly into the hull can be very desirable.
     
  8. TANSL
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    TANSL Senior Member

    Indeed, GRP, it would be normal to build this bulb with a separate mold, and glue it to the hull (padded with foam).
     
  9. bhnautika
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    bhnautika Senior Member

    TANSL brings up a good point about always keeping in mind the limitations and requirements of the materials and the processes that may be used in construction, also is there a need to model every detail in 3d when the construction drawings are 2d and could show more detail. Maybe a mix of both?
     

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  10. TANSL
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    TANSL Senior Member

    I totally agree with you, bhnautika.Design something that can not be built, or which will not sail correctly, it is completely useless and does not speak well of knowledge of the designer. That, unfortunately, is too often in this forum. Many people calls itself "boat designer" and show us their "vases".
    3D models much help detect problems, are essential in our times. The drawback is that not everyone is capable of building such a good model to detect these problems. Indeed, a combination of 2D and 3D drawing is necessary.
     
  11. yofish

    yofish Previous Member

    Vases can be pretty though, and if you have the equipment (1st pic) and skills? Scale plays in too. Obviously the larger the vessel, the 'easier' to make.

    Second pic is a boat a friend is having built by Fred Wahl, Oregon, showing the 'inserted' method.
     

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  12. TANSL
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    TANSL Senior Member

    You talk like an open book.
    Among your photograph No. 1 and drawing on post # 4 there are differences, I'm sure, you've been able to detect. As you know well, small differences can separate what is buildable from what is not.
    Nor is it logical to design something with serious construction problems. Do not you agree?
     
  13. yofish

    yofish Previous Member

    Your second sentence makes no sense to me. Most anything is 'buildable' if, for example, you are the US Government.

    The third sentence I agree with as being rather obvious but if you're saying the only way to do a bulbous bow is to 'stick it on' then I disagree.
     
  14. TANSL
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    TANSL Senior Member

    Yofish, I see you do not want, or you don´t know how, to treat the issue seriously. I'm serious so I will not continue with this topic. Cheers.
     

  15. Grey Ghost
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    Grey Ghost Senior Member

    What detail would make this take thousands of hours to build in your opinion?
    I've never welded in my life and worked only for one week as a volunteer shaping metal so be gentle. I know I could do this in fiberglass with enough sanding ;)
     
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