Laminating lay up schedule VS LOA

Discussion in 'Boatbuilding' started by victor biacolo, May 14, 2018.

  1. victor biacolo
    Joined: May 2018
    Posts: 7
    Likes: 0, Points: 1
    Location: Philippines

    victor biacolo Only JESUS is the real boat captain

    Hello Folks,

    Do I want to know the total lamination of fiberglass reinforcement versus L.O.A?
    I am planning to build 85 footers X (D-16' & B-12') boat with outrigger.

    According to DNV-GL, for "Hull skin minimum of 4.2 KG/Sq. m and 6 KG/Sq.m for Stem and Keel"

    DO you have any reference manual or books showing numbers of lamination (i.e 10th layer) with respect to its LOA. Thank you
    9029087315_01490187b9_o.jpg
     
  2. jehardiman
    Joined: Aug 2004
    Posts: 2,293
    Likes: 161, Points: 63, Legacy Rep: 2040
    Location: Port Orchard, Washington, USA

    jehardiman Senior Member

    Because the loads are so different between different types of hulls for the same length there is no "LOA=x layers" for larger hulls; you have to calculate it for each specific situation especially if using cores. For modern engineered layups with cores, check out the work of S. W. Tsai specifically THEORY OF COMPOSITES DESIGN. 2008. For older/hand layup solid glass and polyester workboat design you can still use Marine Design Manual for Fiberglass Reinforced Plastics. by Gibbs & Cox. 1960 as a good place to start.

    https://ia800205.us.archive.org/20/items/marinedesignmanu00gibb/marinedesignmanu00gibb.pdf
     
  3. TANSL
    Joined: Sep 2011
    Posts: 5,259
    Likes: 129, Points: 73, Legacy Rep: 300
    Location: Spain

    TANSL Senior Member

    Magnificent book. Thank you.
    To begin with, since apparently Victor knows the DNV-GL, in that regulation he can find a lot of help.
     
  4. victor biacolo
    Joined: May 2018
    Posts: 7
    Likes: 0, Points: 1
    Location: Philippines

    victor biacolo Only JESUS is the real boat captain

    Nice books as reference for FRP boat building... Thank you
     
  5. rxcomposite
    Joined: Jan 2005
    Posts: 1,784
    Likes: 109, Points: 63, Legacy Rep: 1110
    Location: Philippines

    rxcomposite Senior Member

    All your knowledge to be gained about Class design will mean very little. These type of traditional boat is regulated in the Philippines by MARINA and must be built in accordance with the guidelines they have drawn up. Ask MARINA if they have finished the FRP guidelines they have been working on. Last time I participated in the board meeting, the officers were adapting the NK standard and a draft was made. There was also a move to look at ISO standards. Be guided accordingly. Ask the nearest satellite office.
     
  6. victor biacolo
    Joined: May 2018
    Posts: 7
    Likes: 0, Points: 1
    Location: Philippines

    victor biacolo Only JESUS is the real boat captain

    Hello composite, Last year I asked MARINA about FRP Guidelines and unfortunately, they don't guidelines yet. So we relying only upon DNV-GL that "Hull skin minimum of 4.2 KG/Sq. m and 6 KG/Sq.m for Stem and Keel".

    1. For Hull Skin of 4.2 kg/sq.m is equal to 3 plies of WR800 + 4 plies of CSM450 + 1 plyCSM300 (Total of 9.34 mm), but I advised to my Naval Architect we will lay up to 10 layers (11.73 mm)
    2. For Stem and Keel 6 kg/sq.m (11 layers - 13 mm) but we prefer to lay up to 15 layers (18.11 mm)

    Do you think it is ok sir?
     
  7. rxcomposite
    Joined: Jan 2005
    Posts: 1,784
    Likes: 109, Points: 63, Legacy Rep: 1110
    Location: Philippines

    rxcomposite Senior Member

    Victor- Composite design is a lot more than what you are describing/or overdoing it. There are many many rules to be followed and satisfied. I can suggest several ways to do it.
    1. Ask your Naval Architech to do the research. It is now required by the State to for the plans approval to be signed/reviewed by an in house Naval Architech. It is his license on the line.
    2. Get a copy of NK rules on FRP. It is the one they are following. You can get it from MARINA.
    3. Ask your NA to contact the Filipino NA guy who now works as a surveyor in NK. Can't post his name here without his permission. Everybody knows each other so there should be no problem.
    4. PM me if you cannot find someone to do FRP design.
     
  8. victor biacolo
    Joined: May 2018
    Posts: 7
    Likes: 0, Points: 1
    Location: Philippines

    victor biacolo Only JESUS is the real boat captain

    Hello composite - since the Guidelines for FRP by MARINA is not published yet, we use DNV-GL and LLOYDS standards and specification. The Vessel Plan has been signed already by MARINA with Authority to construct. I just trying to post here to obtain more information for my own knowledge and future expansion of my project.

    I really appreciate your suggestion to pm you in my future requirements.
     
  9. rxcomposite
    Joined: Jan 2005
    Posts: 1,784
    Likes: 109, Points: 63, Legacy Rep: 1110
    Location: Philippines

    rxcomposite Senior Member

    There are many here in the forum (one is even in Samar) who is knowledgeable on layups but nobody pitched in because of the lack of data to stand on.
    1. Minimum skin thickness- is dependent upon the location (bottom, sides, deck, superstucture fwd, aft), the individual thickness is dependent upon the glass content of varying fibers used. The minimum is just that, you cannot go below that to satisfy the rule but to design around minimum, there is load pressure (or reduction thereof), frame spacing and span, panel ratio, strength resulting from mix of CSM and rovings, and stacking sequence.
    2. Stem and Keel Plate have two different minimums. For example, the keel as defined in LR rule 3.2.3 is dependent upon rule 3.2.1. Keel plate is dependent upon length and the freeboard. Stem plate thickness starts with keel plate thickness and diminishes as it moves away from the Fore Perpendicular.

    You cannot just increase thickness just because you think or feel that way. If you are using LR, there are loads and loads of formulas to go by and you have to prove it.
     
  10. victor biacolo
    Joined: May 2018
    Posts: 7
    Likes: 0, Points: 1
    Location: Philippines

    victor biacolo Only JESUS is the real boat captain

    Hello composite,

    Good morning.... upon checking the CLASSNK TRG 14-510 Standards, is same with DNV-GL the difference is DNV-GL is using the total amount of Fiberglass with respect to its total surface area (i.e. 4.2 kg / sq.m) but in CLASSNK is good because is a direct calculation of thickness considering Lenght of the boat, draught & web framing are given. Thank you for the suggestion to review classnk standards.

    Untitled.jpg
     
    Last edited: May 19, 2018

  11. rxcomposite
    Joined: Jan 2005
    Posts: 1,784
    Likes: 109, Points: 63, Legacy Rep: 1110
    Location: Philippines

    rxcomposite Senior Member

    You are welcome. I used NK a long time ago. I suggested NK so you won't be very far off if ever the controlling body issues its guidelines as it seems they have adopted the NK standard,

    The next thing to know is how to calculate design pressures on bottom, sides, deck, ect. The pressure determines the thickness of the laminate based on the spacings/span and length of panel which defines PANEL SIZE.
     
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.