Identifying a Cored Hull

Discussion in 'Downeast Boat General Discussion' started by Brainey, Dec 6, 2017.

  1. Brainey

    Brainey Senior Member

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    Gents,
    Back on the hunt and was looking for some advice. I am looking at a boat built in 1989 and there is some uncertainty about the construction methods. I've contacted the builder, who does not have records available, but says some of the boats in that era were airex cored. The current owner and broker believe its solid glass, or at least solid to the waterline, but no evidence exists other than the owners observation that he could see light through the hull when it was hauled. He claims that's proof that it is not cored. Short of drilling holes in the boat is there a way to resolve this uncertainty? Thanks.
    Bill
     
  2. F/V First Team

    F/V First Team Captain

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    Look under the deck for a transition of thicker hull to thinner hull, that will be the obvious line where the core begins.

    Or you could give it a tappity tap tap with your knuckle and conclude based on your findings.
     
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  3. Brainey

    Brainey Senior Member

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    Thicker being where the core is? So if there is not transition then it's either all glass or all core? Regarding the tappity tap tap the boat is a looooong way from VA!
     
  4. Brainey

    Brainey Senior Member

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    And thanks FT
     
  5. F/V First Team

    F/V First Team Captain

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    You got mail
    And yes, if there is no noticeable transition in the hull there stands a very good chance of it being solid glass or cored all the way down into the turn of the bilge. Fun times either way really. HOW much fun is totally up to the owner.
     
  6. ArchHibb

    ArchHibb Senior Member

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    The switch from solid glass to core on my hull occurs at the stringers, so there’s no noticable transition. Would strong magnets (one outside, one inside) work? Probably stick through 1/2” of glass, but fail with 1/2” or greater core + glass.
     
  7. Shor2832

    Shor2832 Senior Member

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    Have the broker pull a fuel vent, or any other piece of hardware that penetrates the hull. If it is still unsure take a core sample from the inside. The "can see light" explanation seems a bit flimsy of an argument to me.
     
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  8. Brainey

    Brainey Senior Member

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    Thanks for the help guys. I had thought about asking to pull a vent or even a through hull but if I understand the correct method those areas should have been de-cored and filled so I should not be able to see coring in those penetrations even if it is a cored hull.
     
  9. goin4broke

    goin4broke Captain

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    This can be a tough one. You might place a call back to the builder and ask if there was a point where solid glass and coring would transition. If he says i did it at the request of the customer you maybe back to square one. Drilling a hole would be definite confirmation and easily repaired.

    The light thing does hold some premise. Before building my shelter over my boat you could definitely see light coming through the hull (solid glass) but not through the top (cored). However no light will penetrate bottom paint.
     
  10. Bill_N

    Bill_N Captain

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    Look along the edge of the radius where the keel transitions to the hull on both sides.
     

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  11. Keelboater

    Keelboater Captain

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    I agree with the translucent characteristic of solid glass hulls being a good indicator, but not with painted or dark colored hulls. If you can't find the obvious tell tale signs of coring and are a serious buyer, then by all means drill baby drill! It's really not a big deal despite what so many sellers claim.......unless they are hiding something.
     
  12. southshore30

    southshore30 Senior Member

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    Look at the areas where the through hulls are and see if the core was cut back and glass layed in to protect water seepage into the core. If you see a large tapered area around a sea cock it’s probably a cored Hull. Look up under the gunnel and at the very top the core usually stops and is solid glass
     

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