hull scantling

Discussion in 'Boat Design' started by sidali, Jun 16, 2020.

  1. sidali
    Joined: Jul 2017
    Posts: 6
    Likes: 0, Points: 1
    Location: algeria

    sidali Junior Member

    hello every body ,
    i need help please , i want to know about the "spacing (s)" and the "span (l) " to do a scantling of a boat, i don't understand the difference between the span and the spacing ,
    my email is :
    sidaliboualam35@gmail.com
    thank you
     
  2. bajansailor
    Joined: Oct 2007
    Posts: 3,599
    Likes: 1,563, Points: 113, Legacy Rep: 37
    Location: Barbados

    bajansailor Marine Surveyor

    Hello sidali,

    The 'spacing' might typically refer to the distance between the transverse frames in the boat.
    Or the distance between any other structural members, such as hull stringers, deck / roof beams etc.

    The span might typically refer to the length of an item of the structure that is unsupported, such as the length (or width) of the transverse deck beams or roof beams in the cabin.
    If you have a vertical pillar on the centreline of the boat supporting the roof or deck beam, then the effective span would be half of the beam (width) of the boat at that location.
    And if you reduce the span, then you can generally reduce the size of the structural member - conversely, the longer the span, the stronger the member has to be (for example, by making a transverse deck beam deeper to increase it's modulus and resistance to bending).
    This is a very generalised statement though.
     
  3. rxcomposite
    Joined: Jan 2005
    Posts: 2,752
    Likes: 608, Points: 113, Legacy Rep: 1110
    Location: Philippines

    rxcomposite Senior Member

    Most panels are designed to have a short side and a long side for efficiency. The span or length is the long side and the spacing or "s" is the short side.
    In a longitudinally framed boat, the stiffeners or longitudinals run from the bow to stern and is supported by transverses which are spaced longer, thus, the spacing of the longitudinals is s (or b for breadth) and the spacing of the transverse is l. This is a common arrangement.
     
    Last edited: Jun 16, 2020
    bajansailor likes this.
  4. rxcomposite
    Joined: Jan 2005
    Posts: 2,752
    Likes: 608, Points: 113, Legacy Rep: 1110
    Location: Philippines

    rxcomposite Senior Member

    Boats which are "fat" or has a much wider girth are transversely framed. The transverses are closer together and the longitudinals are spaced longer. This is the exact opposite. The long span of the panel is l and the spacing of the transverse is s (or b, breadth). l and s describe the panel size.
     

  5. sidali
    Joined: Jul 2017
    Posts: 6
    Likes: 0, Points: 1
    Location: algeria

    sidali Junior Member

    thank you very much for your help
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.