Loading ...
Sorry, an error occurred while loading the content.

Re: [bolger] Re: Plywood Again??? Forget Marine Ply!!!

Expand Messages
  • Bruce Hallman
    ... Strength. There are different types. Bending, compression, shear, torsional and tensile. The strength issue with boat hulls is complex and a mix of all
    Message 1 of 49 , Jan 5, 2008
    • 0 Attachment
      > Glassing on the outside adds durability but little strength unless thick and heavy.

      Strength. There are different types. Bending, compression, shear,
      torsional and tensile.

      The strength issue with boat hulls is complex and a mix of all these,
      but the largest component of strength in hulls is the shell effect
      which comes mostly from tensile (and compressive) strength.

      Fiberglass has awesome tensile strength properties and good
      compressive strength too.

      Pull a single fiber strand out of fiberglass cloth and try to break it
      with your bare hands to see.
      Fiberglass adds much more than just durability, it adds tremendously
      to the tensile strength of plywood.

      I agree that large ply voids degrade shear, bending and torsional
      strength, but I don't see that those are the most important types of
      strength with fiberglassed plywood boats.
    • Hajo Smulders
      That s exactly what I did. I don t know how thick their skins are; but If I were in a position to order a boat build that way I d insist on a filling of the
      Message 49 of 49 , Jan 9, 2008
      • 0 Attachment
        That's exactly what I did. I don't know how thick their skins are; but If I
        were in a position to order a boat build that way I'd insist on a filling of
        the slots at leats with more foam.
        I really don't claim or want to argue my point beyond the fact that I looked
        at it in a very amateurish way; but decided I didn't trust this method; or
        voids and gaps between skin sheets in a composite.
        Now no matter how wrong I might be; I'm never going to be particular happy
        in a boat that has this issue; so I avoid it.

        Hajo

        On Jan 8, 2008 11:31 PM, Stefan Probst <stefan.probst@opticom.v-nam.net>
        wrote:

        > --- "Hajo Smulders" <hajosmulders@...> wrote:
        > > Slots were probably up to an half an inch wide in a 2 inch piece
        > > of foam at the 'open side' of the curve. These were gaps; not voids.
        >
        > Something like on
        > http://www.amateurboatbuilding.com/articles/howto/foam_sandwich/index.html
        > under the headline "Wide foam sheet planking"?
        >
        > Seems to be ok there.
        >
        > Stefan
        >
        >
        >


        [Non-text portions of this message have been removed]
      Your message has been successfully submitted and would be delivered to recipients shortly.