mast weight difference

Discussion in 'Sailboats' started by SeriolaDumerili, Dec 20, 2015.

  1. SeriolaDumerili
    Joined: Sep 2010
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    SeriolaDumerili Junior Member

    I have to change my Selden mast. A fisherman boat hooked with crane the shroud while my boat was moored in her regular berth. The mast damage was terminal.
    The existing mast profile C138 (3.44 Kg/m) is discontinued and I have asked Selden and Sparcraft for a new mast.
    The nearest Selden profile at the moment is C156 (3.71 Kg/m).
    Sparcraft offered me a profile S330 (4.87 Kg/m).
    BTW, the mast is keel stepped and 15,6 m long. The boat is racing/cruising 9,5m.
    I have few questions:
    How much weight difference (%) can be acceptable for a new rig?
    How much weight (%) can I save with rod rigging comparing to standard wires (8mm and 7mm)?
    thank you in advance
     
  2. gonzo
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    gonzo Senior Member

  3. SeriolaDumerili
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    SeriolaDumerili Junior Member

    Ok, I can save 20%, up to maybe 30%. In my case about 3-4 kg. Any advice about mast weight? I think that the mast offered by Sparcraft is to heavy.
     
  4. gonzo
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    gonzo Senior Member

    A difference of 0.28 Kg per meter is only a total of about 4.2 Kg. Some of it will be buried under the deck and affect stability very little. Overall, it won't make a huge difference. However, if you are racing competitively, a few hundreds of a knot make the difference between winning and losing. A heavier mast section may be able to use slightly smaller rigging wire, which would compensate for the difference.
     
  5. DGreenwood
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    DGreenwood Senior Member

    Keep in mind that a large proportion of the weight aloft is stuff other than the spar. Spending a little more on better standing rigging or running rigging or fittings can often put you ahead weight wise cheaper and safer than going for the lightest spar. I have seen people drop $30k on a carbon spar when they would have achieved the same result spending $10k on lighter running rigging and fittings.
    In your case I would take the time to analyse the weight situation with the all the other things you are going to put back on the mast and try to save 4 kilos somewhere else. 1/2 a kilo at the mast head would cover you.
     
  6. fastwave
    Joined: Jan 2007
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    fastwave Junior Member

    There are other spar manufacturers. All the comments above are correct but why pay mire money to fix something that you do not need to buy in the first place.
    Sometimes the spar manufacturers overdimension their offers to avoid issues. Talk to them. Your old mast stood up fine so there should be no need for a inscrease in strength.
    Perhaps the old section had bigger dimensions which increases the I.

    I would do a bit more digging before accepting a heavie mast.
     
  7. SeriolaDumerili
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    SeriolaDumerili Junior Member

    What other EU spar manufacturer would you suggest? I appreciate any advice.
     
  8. SukiSolo
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    SukiSolo Senior Member

  9. fastwave
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    fastwave Junior Member

    The biggest driver for mast section sizing that is usually unknown is the righting moment. Make sure you have the correct data and talk to the manufacturers if perhaps for your righting moment you could have a section one size smaller.
     
  10. SeriolaDumerili
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    SeriolaDumerili Junior Member

    comparing to other boats I think that the boat should benefit with lighter rig.
    [​IMG]
     
  11. Stumble
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    Stumble Senior Member

    I would also point out that now is the best chance you will ever have to replace your mast with a carbon one. Since insurance is picking up the cost of a replacement alumnium one I would at least check on the cost of the upgrade. Carbon prices have been coming down a lot recently.
     
  12. SeriolaDumerili
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    SeriolaDumerili Junior Member

    Selden representative told me that the carbon mast is Al mast * 4, so I was little afraid to ask for a carbon stick :). I have heard for Pauger on the lower price side
     
  13. Stumble
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    Stumble Senior Member

    It really depends on the mast, but it has been a long time since cf was four times the price of always depends on the boat, and where it is of course, but a more realistic figure is about 1.75 times the price of an aluminium mast by the time you take into account the rigging and shipping costs.
     
  14. bjn
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    bjn Senior Member


  15. SeriolaDumerili
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    SeriolaDumerili Junior Member

    Shipping and rigging work will be the same for both masts. For carbon mast maybe much simpler - I am delighted with Pogo 30 carbon mast with just one pair of spreaders, and it have same sail area like mine boat.
     
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