Another way to design & build in Aluminium boats

Discussion in 'Metal Boat Building' started by monomad, May 17, 2014.

  1. TANSL
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    TANSL Senior Member

    Forgive my ignorance but I do not see why. The hull front part is above water.
     
  2. monomad
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    monomad Junior Member

    Tansl In rough water the bow is the part that is cutting through the water.
    Having a boat running on the back part of the hull at speed partially smooth water then hitting the wash of another boat ( hang on ) I hope the driver is experienced.
     
  3. TANSL
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    TANSL Senior Member

    Drag has two major components, among others: frictional drag and wave making resistance. The first is less than the second and the first, in the bow area, may be negligible. If so, why so complicated ways to get a decrease in rag that, assuming that is achieved, it is negligible ?.
    I should give figures to support what I say and do not have but maybe it would be nice you to reflect on the matter.
     
  4. yofish

    yofish Previous Member

    "I should give figures to support what I say and do not have but maybe it would be nice you to reflect on the matter."

    Say what?
     
  5. monomad
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    monomad Junior Member

    Tansl, for all those who quote figures Why haven't they come up with the perfect HULL?
    How many hulls once built have performed exactly to the computers figures.
     
  6. Ad Hoc
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    Ad Hoc Naval Architect

    Like everything, it depends upon your perspective. The "perfect" hull, is one that does what is required in the SOR, that's it.

    Can't speak for others, however, we can in general (for us), say all of them; bar the odd one or two. Its the norm not the exception. Again, it's all about perspective. If you're an amateur your perspective is rather different to that of a professional.
     
  7. gonzo
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    gonzo Senior Member

    Most professional computations usually err on the conservative side. Many vessels exceed expectations. I think that on recreational boats, performance varies more because of the unexpected loads (owner's stuff) that gets added through time.
     
  8. monomad
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    monomad Junior Member

    If your an amateur your perspective is rather different to that of a professional.( Ad Hoc )
    Most professional computations usually err on the conservative side. ( gonzo )

    Well I must have a different perspective because I am not what some would call a professional. I don't have a trade certificate in boat building ore design and I certainly have not been to university.
    I use my Design cad program on my computer to draw what I have in my head then I can look at it to see where I can improve. I have designed boats from 4m to 30m, Cats and Monohulls and I can say that all of my hulls have performed to and above requirements.
    Here is a 30m Cat I designed in the late 1990s
     

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  9. baeckmo
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    baeckmo Hydrodynamics

    Ok, fine; who built it and to which rules, and where is it now?
     
  10. monomad
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    monomad Junior Member

    baeckmo I put a tender in but missed out on building it. Designed to DNV.
    Here is a 23m mono with 3 jets I designed and built but had to walk away before it was finished.Under quoted. That was built in 2000 to USL code and is still working
     

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  11. Mikeemc
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    Mikeemc Junior Member

    Been there done that , good schooling :)
     
  12. Ad Hoc
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    Ad Hoc Naval Architect

    So, it is a paper design not a real design then?
     
  13. yofish

    yofish Previous Member

    "So, it is a paper design not a real design then?"

    Now, that is a statement that I do not understand at all from one who is supposedly a 'naval architect'. Do you mean to tell us that your 'paper designs' are not 'real designs'?

    "Hey Bubby, I have this har plan, but she ain't a real plan cause she's on paper and therefores ain't real but don't worreez cause I gots the real plan in me haid and no worreez, mate!" I can dig it, if this is the case but c'mon, really?
     
  14. Ad Hoc
    Joined: Oct 2008
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    Ad Hoc Naval Architect

    Clearly you're not a naval architect, thus i'll explain.

    A claim was made about a vessel, noted here:

    Where it was questioned. The question being where is the data/info on the vessel. Noted here:

    The reply to the question is here:

    Thus whatever claim is made about the design it was not built and thus remains a paper design only. Anyone can make claims on paper designs. A design that has been built by a shipyard and built to class, is not a paper design. Thus, such a vessel now built can prove and demonstrate such claims that were originally cited.
     

  15. yofish

    yofish Previous Member

    You know what? With all due respect, I think you're full of 'professional' crap!

    plan (plăn)
    n.
    1. An orderly or step-by-step conception or proposal for accomplishing an objective: a plan for improving math instruction.
    2. A proposed or intended course of action: had no plans for the evening.
    3. A systematic arrangement of elements or important parts; a configuration or outline: a seating plan; the plan of a story.
    4. A drawing or diagram made to scale showing the structure or arrangement of something.
    5. In perspective rendering, one of several imaginary planes perpendicular to the line of vision between the viewer and the object being depicted.
    6. A program or policy stipulating a service or benefit: a pension plan.

    Nowhere is to be found in these accepted definitions is your special 'naval architect' meaning of a plan . I'm quite certain that there were numerous 'plans' made for the Space Shuttle. These were 'real' plans in that they existed; they could be retrieved, reviewed and modified. THEY ARE ACTUAL PLANS! Your so-called 'real plan', IMO, is pure mental gymnastic baloney.
     
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