Help - Pressure depressions in fiberglass foam sandwich hulls - seeking repair advice

Discussion in 'Multihulls' started by Gone Troppo, Jan 10, 2015.

  1. Gone Troppo
    Joined: Jan 2015
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    Location: Broome

    Gone Troppo New Member

    Small depressions (<1mm) in hull

    Small depressions (<1mm) in hull -
    Inspected by those in the know- cosmetic only. Thanks for the advice
     
    Last edited: Jan 11, 2015
  2. rogerf
    Joined: Apr 2012
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    Location: port stephens

    rogerf Junior Member

    Hi Gt

    Did you have the boat surveyed prior to purchase?

    If not it might be a good idea to seek professional advice. I would be concerned as to the nature of the core material and moisture content.
     
  3. Gone Troppo
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    Gone Troppo New Member

    Thank you for the replies. Spoke with the builder - cosmetic.
     
    Last edited: Jan 11, 2015
  4. waikikin
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    waikikin Senior Member

    GT,

    very unfortunate. Surely there's some help in Broome for a closer look, an old workmate used to live there(not now though) & work as Shipwright in the dry.... & in the bottlo in the wet. If there's boats there, someone will work on them.
    It's not uncommon for foam sandwich hulls with light skins to get bruised, particularily along pontoons & the like, your buoy must have some nasty ribs! At least tap test the area & gently remove paint & filler... is there kevlar on the outside? I've never personally worked on kevlar or its repair, apparently has its own issues. So you can see the condition of the external laminate, some design info would be handy as to existing laminate, or substitute as apparent.
    Have you checked internally for any expression in the area?
    If you have insurance I'd be going down that path.
    Jeff.
     
  5. rogerf
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    rogerf Junior Member

    GT

    Best to get a second opinion, perhaps also a core sample of dented area
     
  6. waikikin
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    waikikin Senior Member

    The Builder would be a good start, don't get much better than him.
    Jeff.
     
  7. Mr Efficiency
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    Mr Efficiency Senior Member

    Maybe the Kevlar has saved it from fracturing, it has an ability to dent, that glass alone seemingly does not.
     
  8. dinoa
    Joined: Oct 2007
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    Location: florida

    dinoa Senior Member

    Often locally heating a depression in sandwich with a heat gun will help it resume its previous shape. From your pictures though I think the extent of deformation is beyond that fix.

    Dino
     
  9. BobBill
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    BobBill Senior Member

    What pictures? I was lurking to hold solution, if any. Wondering if the interior of sandwich might need fix...
     
  10. Mark Fisher
    Joined: Dec 2014
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    Location: Takoma Park MD

    Mark Fisher Junior Member

    As BobBill commented, this thread seem to refer to another thread or something.
    • I'm interested in the topic, but a 1mm depression is pretty small. Is that diameter or depth?
    • Kevlar is mentioned in several of the responses. Why?
    • Again, Pictures?
    Offhand, very small defects in the surface can arise from print-through of woven fiberglass under inadequate mat and gelcoat. Just lookin'
     

  11. waikikin
    Joined: Jan 2006
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    waikikin Senior Member

    Mark,
    The defects were smallish but many & often over four areas, pictures have been removed/edited from post.
    Jeff
     
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