Aluminum Kayak?

Discussion in 'Materials' started by Tedd McHenry, Dec 14, 2020.

  1. Tedd McHenry
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    Tedd McHenry Junior Member

    I've been attempting to learn how to design a kayak, working in SolidWorks. (Mainly because I already own it and know how to use it.) I've limited my designs to developable surfaces, for now, because I'll probably start with stitch and glue construction. But I have a pretty comprehensive set of sheet metal tools and experience using them, from an airplane project years ago. It recently occurred to me that it might be possible to make a pretty good kayak in aluminum. My initial calculations suggest that it might be slightly lighter than a wood kayak. Or, at least, not heavier. The wall thickness will be very small and I'm not a very good welder, so, rather than weld it I thought I might frame the bulkheads and longitudinal members using flush rivets, then join the skins to the frame with adhesive. Not sure how I'd seal the seams--maybe silicone or marine sealant. But the adhesive joints would be the primary sealant.

    So, why would this be a bad idea?
     
  2. bajansailor
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    bajansailor Marine Surveyor

    The Grumman folk (who I think originally built the Grumman Goose seaplane) build aluminium canoes commercially - here is a video of the process that they use.


    They do not use developable surfaces though; rather, the aluminium sheet is pressed into shape.
     
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  3. Tedd McHenry
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    Tedd McHenry Junior Member

    Thanks, @bajansailor . I remember those Grummans from when I was a kid. I grew up on Ontario and they were popular in that area.
     
  4. Barry
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    Barry Senior Member


    Discontinued. Same manufacturer as the above canoe builder
     
  5. Mr Efficiency
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    Mr Efficiency Senior Member

    So long as you don't put an ungloved hand on them in winter ! I think I'd keep silicone away from aluminium, though.
     
  6. hoytedow
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    hoytedow Fly on the Wall - Miss ddt yet?

    I would use Loctite concrete patch. It works well and cheaper than 3m 5200.
     
  7. Barry
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    Barry Senior Member

    Last edited: Dec 16, 2020
  8. BlueBell
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    BlueBell "Whatever..."

    It won't be the first time he rolls it.

    Tedd,
    I've never seen an aluminum kayak.
    Another option would be skin-on-frame (SOF),
    making the frame and bulkheads aluminum
    and then wrapping it, traditionally.
     
  9. gonzo
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    gonzo Senior Member

  10. Tedd McHenry
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    Tedd McHenry Junior Member

    Oh man, I would love to do that! I've always wanted to learn that English wheel stuff. Maybe for my second kayak!
     
  11. Tedd McHenry
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    Tedd McHenry Junior Member

    Thanks, I'll look into that. It gives me another idea, too. I know a guy who works for Loctite and is really knowledgeable about all their products. I'll see what he recommends.
     
  12. Tedd McHenry
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    Tedd McHenry Junior Member

    Yeah, I've been wondering if some kind of lacquer finish would be a good idea. But unpainted aluminum airplanes are just polished, and the surface area of a kayak isn't much, so the easiest thing might be just regular polishing.
     
  13. DCockey
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    DCockey Senior Member

    Deformation due to loads/impacts on small areas could be the limiting factor in how thin the skin can be.

    What would you use for the longitudinal members at the keel and chines? Would you try to use a shape which matches the angle of the adjacent panels, or rely on lots of adhesive/sealer to fill the gaps?
     
  14. upchurchmr
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    upchurchmr Senior Member

    Aluminum kayaks are going to make a horrible banging racket.
    Unless you are very sophisticated they will be heavier than anything else.
    And they take a permanent dent really easily.

    Just say no.

    But you could polish it up enough to blind everyone and all the fish on the lake!
     

  15. Tedd McHenry
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    Tedd McHenry Junior Member

    My preliminary CAD analysis suggests it will be no heavier that wood, and most likely lighter, by comparing identical designs in wood and aluminum. On what basis do you think it will be heavier?
     
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