New build question

Discussion in 'Boat Design' started by Pietr Belosguardo, Oct 27, 2019.

  1. fallguy
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    fallguy Senior Member

    The Laguna Madre can be build round chine. Just so you know..
     
  2. gonzo
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    gonzo Senior Member

    No, they don't want to make it easy for people to copy or modify the design and call it their own. The boat you posted has a complex shape. It is not a beginners project. Further, to build a fiberglass boat, first you make a plug, take a mold off the plug and then build the parts inside the mold. Basically, you build three boats to get one.
     
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  3. Pietr Belosguardo
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    Pietr Belosguardo Junior Member

    Thanks for the answer. This is probably why i can't find what i'm looking for! Here is what i'm thinking of doing: If i build a mold with the stations on a frame and use strip planking to shape the hull, i should be able to construct a Foam core on the plug (by using epoxy and securing the foam core to the mold). Then i could put a layer of fiberglass over it. I would remove the mold, and then glass the inside. Isn't this possible? Thanks
     
  4. gonzo
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    gonzo Senior Member

    Yes it is. You need to find a design and either loft the lines to make the stations, or have them cut by CNC if the plans are in DXF format. You need to be an experienced professional to get the finish and details of the boat you like. I have built many boats and would estimate that there will be 200-250 hours of sanding and fairing. As a beginner, you can plan on tripling the time and getting an inferior finish. A simpler design, probably a developed form from flat panels, would be more realistic.
     
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  5. fallguy
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    fallguy Senior Member

    plausible, but a bit unnecessary

    unless your hull is really strange; you can build in a female mould

    foam doesn't really require a full hull mould

    it can be built on a female or male skeleton IF the designer provides the foam cutting plans

    only a full glass or carbon hull would require a mould

    if you strip plank the hull form for one off construction; it is also plausible to use the strips as hull, but if you want foam; it seems a bit odd to go that route

    Cerny Yacht design has a nice video on forming foam into a female mould. That would be a good way to go.

    you might end up with a bit of fairing, but it will be a challenge to build on a male plug because the foam will tend to not stay on the form...

    watch the Cerny video... I will link
     
  6. fallguy
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    fallguy Senior Member

    This is a highly accurate statement. We are fairing two 10 meter hulls and it is really hard to get right.

    And this is the reason stitch n glue is such a winner for home builds..
     
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  7. fallguy
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    fallguy Senior Member

    Here is the link.



    Here is a picture of a raw foam hull build from a female jig prior to fairing.

    EF66D766-7B2B-40E5-924A-8A79DD86E6A5.jpeg

    As Gonzo said, this hull will take about 400 hours to fair and paint; perhaps 600. We like to forget..
     
  8. fallguy
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    fallguy Senior Member

    Here is the partially faired starboard hull with a crude coat of primer on.. I'd rather not think about the hours because we made a few mistakes that cost us about a week (lost time). 87E53F70-AB2F-4129-BD3A-98B758B3A487.jpeg
     
  9. Dejay
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    Dejay Senior Newbie

    For building with foam I'd look into intelligent infusion for e.g. the T60 linked earlier. Or any kind of develop-able hull and vacuum infusion. It's more complicated but from what I read it should save quite a bit of time fairing and reduce epoxy. I have no personal experience though.
     
  10. Pietr Belosguardo
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    Pietr Belosguardo Junior Member

    Thanks again for the answers. I had seen the Cerny video and it is what started my interest in foam core sandwich construction. It is a bit discouraging to think you need to sand 300hrs for a 17 feet long hull... There should be a quicker way! Anyhow, i still want to build something with beautiful lines. I appreciate your time since you need to sand some more!
     
    Last edited: Oct 29, 2019
  11. Eric ruttan
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    Eric ruttan Senior Member

    intelligent infusion is the quick way. No sanding.
     
  12. gonzo
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    gonzo Senior Member

    Intelligent infusion works for developable shapes. It would not be applicable for the design he posted. Further, most of the fairing would be for the interior, gunwales, etc. that have a lot of fillets, curves and other odd shapes.
     
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  13. fallguy
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    fallguy Senior Member

    The boat I pictured is dev panel. The Drake is not. It would be a real bear to fair the Drake as a one off boat.

    The dev panel boat is simpler to fair, but still lotsa work. My tape rebates were just a hair shallow in case anyone is wondering and we also coud have secured the panels middle for less fairing, etc.
     
  14. Pietr Belosguardo
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    Pietr Belosguardo Junior Member

    Car bodyshop do this kind of work all the time, and the shape of a car is complex. I don't think they spend 300hrs for a perfect finish... Anyway, Thanks for the input
     

  15. BlueBell
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    BlueBell . . . _ _ _ . . . _ _ _

    Sounds like you've never done this before...
     
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