Floor Replacement For Aluminum Boat

Discussion in 'Boatbuilding' started by jimquik, May 27, 2008.

  1. jimquik
    Joined: May 2008
    Posts: 1
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    Location: burlington

    jimquik New Member

    I am planning on replacing the floor on a 1977 16' starcraft aluminum boat. I know I have to remove the old floor but I need to know how to remove the shelves and support on the inner sides. I assume that I drill out the old rivets and remove the inner supports/ shelves.

    Where do I buy the rivets and tools for re-installation and are there any other pointers to follow?

    I already know what plywood to use and how to coat it. Any other pointers are appreciated.
  2. alan white
    Joined: Mar 2007
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    Location: maine

    alan white Senior Member

    The rivets may spin when you try to drill them out so I'd suggest grinding the heads off with a fifty grit disc on a right-angle grinder.
    Might be easier to screw the new ply on instead of riveting (rivets are cheaper and faster in a factory, but if you use self-drilling/tapping stainless screws, you'll save a lot of time and aggravation and you won't need a rivet gun. You can coat the screws with a barrier formula to prevent any galvanic corrosion.
    I don't know what you mean by shelves, unless you mean the miscellaneous trim pieces to each side. You're on your own there. Look for fasteners. normally, I see cup washers with screws.
    Or do you mean stringers that support the plywood?

  3. thudpucker
    Joined: Jul 2007
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    Location: Al.

    thudpucker Senior Member

    I had a '57' Starcraft Marlin 16'.
    I put a lot of hours on that boat in Salt water.
    All the rivets came loose. Frequently and constantly.

    One day all the floorboards came out, and I had to overhaul all that.
    At the edges of the floor boards, those rivets went into the ends of the bottom stringers.
    That all eroded.
    The holes were rotted around the edges. The aluminum that was left would not hold a rivet or a screw, even if you backed it up with a big washer.

    There is such a thing as aluminum tubing. It comes in grades so you can get what you want.
    I went to a welder and asked him what to get. He told me, I got it, cut it into little pieces and held it in place as he welded it to the stringer ends again....and again and again and again...
    Eventually we got the whole boat to a point where the wooden bottom could be re-riveted in place. In my boat is was necessary that the floor boards be fixed solidly in place.
    The Floatation was under the floorboards in that boat. Nothing under the seats.
    So I had to find, cut and fit, foam to go under that floorboard and then rivet the floorboard down.
    To make the floorboard, I scarfed two pieces of 3/4" Marine plywood together to make a long piece of floor board. There was a lot of cutting and fitting to get that big long floor board to set down in there flat and evenly.
    That stiffend up the bottom quite a bit. The whole boat was much nicer to handle after that.

    To do all that, I took the Wood part of the transom off the boat, all the seat brackets off the sides of the boat, and the front deck too. So I could reach in and be free of encumbering 'things' and that was a worthwile effort.

    I also added another set of oarlocks so I could row from either seat.

    Aside from that, the middle of the boat had a Keel piece riveted onto the bottom and both sides on the outside.

    There was a big molded piece of Rubber inside that Keel piece and the sides were all riveted to the Keel piece, and the rubber was trapped in there.
    All those rivets rotted out and the holes rotted around the loose rivets.
    The Rubber was part of the water proofing and was no good at all.
    It leaked like a sieve.

    My son helped me (reluctantly) to re-rivet that Keel piece back into place several times. Finally it was just not possible to fix any longer. I had to find a Welder and some pieces of Scrap aluminum and had all that welded in place.

    What a job all that was. I should have sold the boat to the scrapyard and bought a new welded boat.
    Anyway, I didnt.
    I got a lot of use out of that boat. I rowed it half way round the world Fly fishing. Somtimes I wish I had it back, but not on your life would I ever have another one.

    It's benefit was it's light weight. For a 16' boat, a 25 hp motor was just fine and I had a 10 Hp I used on it too.
    Good luck with your project. I think you'll like the boat when you get it finished.
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