Replace plywood strips in my billage floor?

Discussion in 'Boat Design' started by lvl, Sep 5, 2010.

  1. spare parts
    Joined: Sep 2010
    Posts: 11
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    Location: Tampa FL.

    spare parts Junior Member

    The fuel cap in the back may have well been used for a built in fuel tank, there are many outboard built boats desighned with built in fuel tanks..as for the vent By ;law if theres a built in fuel tank there must be a bilge ventilation system installed and in working order. to replace that transom properly you need to cut out the outer layer of fiber glass too. then laminate two pieces of 3/4 marine ply together with two layers of Matt in betwwen the tow plywood layers well saturated then clamped tighty with either clamps or temporary screws. then you can cut the exact shape or the hull into your piece then re glass the entire transom piece back into place as a single unit...Note: if theres a drain plug in the bottom before glassing your new transom back in take 2 inche hole saw and cut a hole through the transom at the correct place for the drain centered. and then on one side put a wax coated backer to cover the hole temporarily then fill the entire hole with shreded matt and resin then re dril that with a smaller hole that will fit your drain plug,, this way water can never get into the edge grain of the plywood. when glassing your new transom back into place , any place the transom will be glassed back in the hull needs to be feather ground several inches back to allow for enough build up to be done with out having an unsightly build up or buldge this also will assure you that youll have enough contact surface to make your repairs structurally sound. i would recomend at least an 8 inche wide taper around the out side of the hull. the inside really doenst need tapered as it wont be an area that needs a nice contoured finish but it will need to be very even and clean for maximum adhesion to the surface use Fab mat after two layers of matt on all the seams where the hull meets the transom including the stringers FAb mat is simply roven and matt thats been bonded togeteher and usually comes in biaxial form.be sure to use a non waxed resin for all your lay up work except for the final layer then you can add a wax agent to your resin that will help with the sanding and not instantly clog your sand paper. youll need to gelcoat most of your work but thats not diffucult and theres some great vidoes and info on youtube to help you understand how to achieve first class results with the gelcoat finish.
     
  2. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Judging by the size and shape of what you've cut out of the deck cap/liner, I can tell you for certain, the boat was designed for both an I/O and an outboard. It's the only thing to explain the huge well inboard of the transom, which looks like an engine box in profile on the forward end. The sump below it is another give away (this is what started the red flags for me any way). It's very probable the hull had several deck cap/liner combinations, one as a bow rider with I/O, one as a bow rider with an outboard, one as a runabout with an I/O, another as an outboard, etc. This is the economical way of having multiple models from the same hull form. I've seen this very hull with several different configurations.

    No big deal, in any case. The transom core has to be removed and replaced, the cut up and de-laminated tabbing needs to be replaced. Then you can start putting things back together assuming no other issues crop up.

    How much outboard HP are you going to hang on that old girl? This will determine how thick you transom core needs to be. She also appears to be setup for a short shaft. Go long shaft, if you can and make the transom cutout higher to suit. It's a much safer and better way to go.

    Spare parts, your description is more work for this particular job, which now has the full inside of the outer skin cleaned and exposed on the transom. Cutting the outer skin at this point would be fruitless. I also don't recommend polyester resins for the novice as it much more difficult to get good results compared to epoxy. You solid laminate drain plug method is a good idea and common practice as are the rest of your polyester application approaches.
     
  3. lvl
    Joined: Sep 2010
    Posts: 8
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    Location: Massachusetts

    lvl Junior Member

    I am coming to terms with having to replace the plywood strips in the floor though I hate the idea of putting something in my lamination tha could rot in the future.

    My newest question is could I put back just two bigger pieces of plywood instead of 6 smaller strips? I removed six strips of 1/2 inch ply that were 2 inches wide. Was thinking of putting back 2 pieces 1/2 inch thick by 6 inches wide. Any thoughts?

    Thx
     
  4. PAR
    Joined: Nov 2003
    Posts: 19,133
    Likes: 480, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder


  5. lvl
    Joined: Sep 2010
    Posts: 8
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    Location: Massachusetts

    lvl Junior Member

    LOL you asked for it PAR.:D

    Sorry for the terriable art work on the pics but here goes. I dont have any pics of the wood I took out. Here is what it looks like now.

    [​IMG]

    Imagine the diffrent colors being individual strips of wood under about a 1/4 inch of glass that were all butted up against each other

    [​IMG]

    Now just two bigger pieces of plywood that I was thinking of putting back.( unless you guys think just mat would be good enough )

    [​IMG]

    P.S.
    I am available for graphic design ;)
     
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