Stainless steel for stringers & floatation chambers

Discussion in 'Boat Design' started by jungerfrosch, Jun 25, 2009.

  1. jungerfrosch
    Joined: Jun 2009
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    Location: Ohio, USA

    jungerfrosch New Member

    I have a 1960's 14' Duo fiberglass runabout that is just a shell with rotten, half gone stringers. Aside from cost would there be any problems with forming stainless steel stringers? My overall idea would be to fill the space between the floor and the hull with a sealed stainless chamber. The chamber would have ribs in the bottom to give the same supporting strength to the hull as the origional stringers. I figure if it's completely sealed, and can't rust then there will never be a problem from water again.

    I do not like the idea of using wood because it will eventually get wet and rot. From all I've read all floatation foams will, in time, absorb water.

    The chamber would be formed to fit the contour of the hull with an english wheel and welded air tight. It would be set resin/epoxy to form a tight no-void contact with the hull. Would this create problems of being too stiff and introduce stress to the hull at the floor?

    I know this would be severe over-kill, but I figured I would post the question to see if there are any disadvantages of such a plan that I am missing.

    Thank you all
  2. PAR
    Joined: Nov 2003
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    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Weight and cost would be obvious disadvantages. It's not a reasonable idea on several levels.

    You could use straight laminate or an inert cored laminate to eliminate the wood.
  3. Guest62110524

    Guest62110524 Previous Member

    you would be far better off using marine grade alloy plate, it welds with less distortion than ss, is lighter, and will not corrode, and sanded foam will stick well to it

  4. jungerfrosch
    Joined: Jun 2009
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    Location: Ohio, USA

    jungerfrosch New Member

    When you say use straight laminate, are you saying to make the stringers a hollow tube section by laying up glass? (i.e. same shape as original but w/o wood and obviously thicker wall than was over wood) What would you use as an inert core?

    I guess I hadn't considered using aluminum. You're right that would be considerably lighter and would also not corrode. Would there be any issue from a strength/fatige point of view in the fiberglass from making the bottom of the boat stiffer than original? I'm not sure that it woud be any stiffer than the plywood floor would have originally made the floor-hull area.

    Thank you for the responses, It's got me thinking along a couple of different lines now.
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