Ideal mountings - foam core

Discussion in 'Fiberglass and Composite Boat Building' started by fallguy, Oct 7, 2020.

  1. fallguy
    Joined: Dec 2016
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    fallguy Senior Member

    I have a number of things to mount in a core build.

    None of the mountings are thru or into hull, but basically onto areas with no ingress worries.

    The most obvious way is to layout and decore to bottom glass and fill, but this process adds a day to any mountings.

    And no way can you move or rearrange things once you decore and fill.

    Are people using mounting plates or what is typical?
     

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  2. fallguy
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    fallguy Senior Member

    Also, I am trying hard to keep weight down on my helm station.
     
  3. Rumars
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    Rumars Senior Member

    Piece of plywood glued to the hull, threaded inserts for the mounting bolts, or glue the bolts into the ply and use them as studs.
     
  4. fallguy
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    fallguy Senior Member

    Don't want the weight
     
  5. Rumars
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    Rumars Senior Member

    Well then just drill a hole and use big flat washers on the other side. If you are worried about crushing the core drill bigger holes and fill with epoxy. Or use a small bent wire in a drill to locally decore a few mm of foam.
     
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  6. fallguy
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    fallguy Senior Member

    Big washers.

    10-4

    Sometimes obvious answers elude me!
     
  7. Rumars
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    Rumars Senior Member

    Aka. fender washers, availale in stainless at you favorite hardware store.
     
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  8. missinginaction
    Joined: Aug 2007
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    missinginaction Senior Member

    Google Structural Washers. Fender washers will typically bend and you'll end up crushing your core. Structural washers are typically 1/8" thick and can be found as thick as 1/4" for really heavy loads.
     
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