fiberglass deck

Discussion in 'Boat Design' started by boatbuilder41, May 21, 2014.

  1. boatbuilder41
    Joined: Feb 2013
    Posts: 162
    Likes: 8, Points: 18, Legacy Rep: 56
    Location: panama city florida

    boatbuilder41 Senior Member

    I have been building decks from fiberglasss panels for a few years. i build the ribs from panels as well. i usually dont use a core unless specified by owner. these decks support a tremendous load. I havent had any problems with these decks at all. And they are light in weight for there size. how come i dont see other builders doing this ???. My fork lift is just shy of 18000 lbs and i can drive it on my deck and park it for hours and it doesnt hurt it at all. it doesnt even phase it at all. it is a little expensive. but not as þad as sðme of the core materials on the market. i was just wondering why i dont see more like this. im just here to learn and become a better builder. so any input or criticism would be appreciated
     
  2. boatbuilder41
    Joined: Feb 2013
    Posts: 162
    Likes: 8, Points: 18, Legacy Rep: 56
    Location: panama city florida

    boatbuilder41 Senior Member

    Herre are a few pic
     

    Attached Files:

  3. boatbuilder41
    Joined: Feb 2013
    Posts: 162
    Likes: 8, Points: 18, Legacy Rep: 56
    Location: panama city florida

    boatbuilder41 Senior Member

    This deck in photos is 12 ft wide x 15 feet long and is installed in two pieces . it is flange bolted st the center line. the ribd are 4 inches wide with a 1 1/2" crown both top and bottom. the ribs are every 12"apart across the beam and run every 24" frrom bow to stern.
     
  4. Petros
    Joined: Oct 2007
    Posts: 2,934
    Likes: 148, Points: 63, Legacy Rep: 1593
    Location: Arlington, WA-USA

    Petros Senior Member

    I would like to understand your process better: are you buying prefabed fiberglass panels and than cutting them into strips to use as your stiffening ribs?

    since you are presumably buying mass produced panels you would be saving some labor, but the configuration of the design would not be optimized for weight. IOW, you may indeed be getting excellent strength for the total cost of the deck, but it will not be the lightest that can be achieved. Most boat designers are trying to achieve the best strength to weight, with costs being a secondary consideration.

    There might be some ways to improve the strength of your deck assemblies with some detail changes. How did you come up with your current configuration, did you have some design help from an engineer or NA?

    why would some customers specify core material and some would not? what kind of vessels are these decks used on?
     
  5. boatbuilder41
    Joined: Feb 2013
    Posts: 162
    Likes: 8, Points: 18, Legacy Rep: 56
    Location: panama city florida

    boatbuilder41 Senior Member

    I actually gort some paanels used in military operations. Rapid runway repair. thats how i ztarted building these decks. they wer 6ft wide and 30ft long and 3/8" thick. i now build my own panels. i cut aall my crown pieces the same and mark the center lines so i have proper alignment of my crown. then i get the center line on my sheet panels and align them all from myy center point. i made a few jig pieces to maintain proper spacing and i tab the ribs to the panels. then i remove the jigs and glass the ribs to the panels with multiple layers of 1708 on both sides of the rib. then i add the ribs properly spaced in the opposite direction. very simple and doesnt really take aas longi as you would think. i build mostly commercial boats. i have been putting these decks in a few charter fishing boaaats and these guys are loving it. i think what they like the most is that i prefab these decks and it cuts down on there down time. i
     
  6. boatbuilder41
    Joined: Feb 2013
    Posts: 162
    Likes: 8, Points: 18, Legacy Rep: 56
    Location: panama city florida

    boatbuilder41 Senior Member

    I haavent had aany engineer or n/a help with these. i know these guys time is valuable aand i tend to overbuild these decks sometimes. but i grew up commercial fishing and i have been in some pretty touggh situations. some being very dangerous.... expecially at the hands of mother nature. keeping this in mind.... i dont personally believe there is such aa thing as overkill when saafety is involved. but i dont know it aaall. and thaats why im here. im here to leaarn from you guys and i have learned aa greaat bit from here. it is said that lifes most valuable lessons learned are learned from failure...... not success...... i just find it a hell of a lot cheaper to get a professional opinion
     
  7. Petros
    Joined: Oct 2007
    Posts: 2,934
    Likes: 148, Points: 63, Legacy Rep: 1593
    Location: Arlington, WA-USA

    Petros Senior Member

    that is the point of using an engineer: to show you how to make the best use of your materials and assembly time. If the engieer cost you more than you save in construction costs, they are not worth hiring (and I say that as an engineer).

    The marine industry has a very long record of types of failures, they categorize different types of boats and uses (off shore vs. coastal vs. inland waters, etc), and than develop tables based on what is "strong enough". Predicting loads on hulls and detailed components on boats in rough waters is impossible to predict. There is a tendency to rely heavily on statistical observations. But even when designed to the best available information, there is always a new or unusual circumstance that was not anticipated. So if weight is not as critical, going strong is always a safer bet. On pleasure boats or passenger ships extra weight actually improves the ride and comfort of the passengers anyway. Heavier also means it will be serviceable longer before it has to be repaired or replaced as well, so there are always beneficial trade offs.

    you can analyze to death a super duper light weight carbon graphite mast on a sailboat, only to have it buckle and fail because it got damaged when something came loose and whacked it, or it gets damaged when trailing the boat to a lake. so extra weight or thickness than is strictly required by design loads is sometimes necessary to make it practical and usable. That is where experience, judgement and knowing the history of how the various components get used (and abused) are often more important than fancy analysis software and specialized education.

    So, you make your panels out of layers of fiber glass and resin, than cut them into strips to make the stringers and ribs? how do you bond them to the deck surface and to each other at the corners?
     
  8. boatbuilder41
    Joined: Feb 2013
    Posts: 162
    Likes: 8, Points: 18, Legacy Rep: 56
    Location: panama city florida

    boatbuilder41 Senior Member

    I cut material to fold into corners and alternate direction of lap with each layer. i hope these pics explain it better
     

    Attached Files:

  9. boatbuilder41
    Joined: Feb 2013
    Posts: 162
    Likes: 8, Points: 18, Legacy Rep: 56
    Location: panama city florida

    boatbuilder41 Senior Member

    Im nott a engineer just a builder... just building the best way i know how. but thats why im asking others what they think. i never got to improve my education beyound vo-tech school when i got marine mechanic certification in 86. My father and grandfather were both builders and commercial fisherman. im not saying we build the best, but we always got to try out our boats first hand... so we kgot to really test our method of building and were always onboard to see how it worked and the failure points... and how to improve.. i dont know how to figure the actual strength of materials and load calculations. If you could tell me how to post a video hhere. i could show you how i stress test the
     
  10. Mr Efficiency
    Joined: Oct 2010
    Posts: 10,386
    Likes: 1,045, Points: 113, Legacy Rep: 702
    Location: Australia

    Mr Efficiency Senior Member

    As an engineered structure, it would be difficult to get maximum uniform strength in all directions, compared to welded metal, would it not ?
     

  11. PAR
    Joined: Nov 2003
    Posts: 19,126
    Likes: 498, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    I would think price point would be the key to not seeing this type of deck build. The bottom line is how much - labor, materials, regulations, etc.
     
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.