Elipetical Birds mouth mast

Discussion in 'Sailboats' started by Chuck Losness, Feb 8, 2016.

  1. gggGuest
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    gggGuest ...

    You also need to consider the capabilities of the material. Carbon is the fibre of choice for spars because arguably its the only one that actually gives a superior result to alloy tube. The other thing you need to consider is the cost of the resin. Supposing you build a spar from epoxy/lumber strap. I bet if you costed it out you'd find the cost of the vast quantities of resin needed to encapsulate the vast quantities of webbing would greatly exceed the total cost of carbon and resin for a carbon spar.
     
  2. gonzo
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    gonzo Senior Member

    That is not correct. The end result is a combination of materials that depend on how the overall composite was engineered. Firstly, "stronger" has to be defined for which properties it refers to. Secondly, a composite with a light weight core will have less tensile, compressive and bending strength than if it was a laminate made of the reinforcement material alone.
     
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  3. Eric Lundy
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    Eric Lundy Junior Member

    Indeed. I agree with that completely. I didn't define exactly what i was rambling about.
     
  4. Steve Wright
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    Steve Wright Junior Member

  5. Eric Lundy
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    Eric Lundy Junior Member

    Yep hence the result of never trying it. I deemed it difficult, not cost effective, and most likely a heavy and terrible result. My rabbit holes go deep sometimes.
     
  6. Steve Wright
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    Steve Wright Junior Member

    Stick with the above-ground bit, and look down kindly on the insane madmen with knit brow who assemble the monstrous machine during the night :eek: maybe make them a coffee..
     
  7. TANSL
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    TANSL Senior Member

    No, that is not necessarily the case.
    For you, what is bending strength?, is it different from tensile or compresive strength?
     
  8. Eric Lundy
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    Eric Lundy Junior Member

  9. Eric Lundy
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    Eric Lundy Junior Member

    Would you like the cut ratios for a 8 sided birdsmouth for a flush outside?
     
  10. Steve Wright
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    Steve Wright Junior Member

    I'm still deciding whether to buy the yacht, not quite ready to make a mast for it! :)

    I wonder if a notch on the outside would provide dividends, in terms of where to locate the spar caps.

    It also seems, that reinforcements in tensile is only half(less?) of the picture. As has been pointed out by others, the engineering issues would have to be worked through one at a time, and then interactions examined. Maybe even a second shroud set ..
     

  11. Steve Wright
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    Steve Wright Junior Member



    Like this.
     
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