Max L/B ratio for a fast cat ?

Discussion in 'Boat Design' started by ryanonthebeach, Dec 26, 2017.

  1. ryanonthebeach
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    ryanonthebeach Junior Member

    No idea what
    They seem to spend more time stroking each others expert egos than contributing.
    Thanks for your input jorge.
    Yes, and as far as I'm aware us amatures are still permitted to design and build our own boats, heck I can build my own experimental plane too... but some folks have a vested interest in making things seem much more difficult than they are
     
  2. ryanonthebeach
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    ryanonthebeach Junior Member

  3. fallguy
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    fallguy Senior Member

    Wow. Richard gave you a super great response first off and you reward him conversing with another poster like that?
     
  4. TANSL
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    TANSL Senior Member

    The reality is that, for many, things are very simple. Are they also for you? Some do not think so and that's why some try to warn you. I think you should be grateful because nobody has forced you to ask here and each one responds as he sees fit.
     
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  5. ryanonthebeach
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    ryanonthebeach Junior Member

    Oh no, I agree it's not simple. Some of it is very complicated.

    My point is plenty of amatures build good boats. Some experts try make it sound like rocket science, becuase they want folks to use their services, buy their boats, some of it is very tricky, but it's not necessary to go to that level, since there are plenty of tools and rules of thumb out there.

    I was simply asking if there was a rule of thumb for L/B ratio out there
    If not I can calculate it, it's not that difficult.
    Whyman and Grrr have some good formulas for estimation and can estimate viscous drag without too much difficulty. Since there are free apps available to calculate wetter surface for a hull design.
     
  6. TANSL
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    TANSL Senior Member

    I agree with you that, perhaps, there may be people who are looking for clients here but, in my opinion, most of them are just trying to help. It is also true that egos are very difficult to control and that people, in the anonymity of the internet, feel more courageous.
    I do not agree, at all, that the world is full of amateurs who design/build good boats. The exception, that you can indicate to me, will not be but the confirmation of the rule and the rule is that to design and / or build a good boat you have to be a very good professional.
    As for the B / L relationship that you were asking, you will have seen that there is a diversity of opinions. If the boat is not speed, the interaction between the hulls will not be large so you can put that of a similar boat, among many you can find on the internet. Apart from this consideration, distribute the boat according to what you want to do with it. Then check the stability and, if you want, perform a power / speed calculation.
    If all that is very easy, better for you. Otherwise, look for a professional. But keep in mind that there are a lot of details that the professional already knows and that the amateur must learn, unfortunately, based on having many dislikes.
    Good luck.
     
  7. BlueBell
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    BlueBell "Whatever..."

    Ryan,
    Stick to your topic and stop feeding the thread derailment.
    When do you start building?
     
  8. TANSL
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    TANSL Senior Member

    Do not be in such a hurry, first he will have to define the boat, do not you think?. Let's go step by step. A saying says "go slowly as I'm in a hurry".
     
  9. fallguy
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    fallguy Senior Member

    Budgets drive boats Ignacio.

    When someone has an open budget; they hire professional help. When they have a limited budget; they typically don’t build cutting edge vessels for minor incremental gain.

    Maximum l/b is just that.
     
  10. TANSL
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    TANSL Senior Member

  11. fallguy
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    fallguy Senior Member

    money drives the plan Ignacio, the plan doesn't generally drive the money for leisure craft
     

  12. ryanonthebeach
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    ryanonthebeach Junior Member

    Good advice blue. Intend to start later this year. Getting a new workshop set up for vacume infusuon and the design together first. Will do as much of the design myself then have a professional vet it, of course...
     
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