Loose footed mains

Discussion in 'Sailboats' started by Polarity, Dec 12, 2003.

  1. motorbike
    Joined: Mar 2011
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    motorbike Senior Member

    Ok seriously boom loading stuff is a sidetrack. Clearly booms arent overloaded by a loose foot, boom design and materials make that irrelevant. If there was a weight penalty or performance penallty then you can bet your last buck the racers would not be using loose footed mains.

    Boom sheeting position plays a far greater role in load distribution. As for PAR's comment on heavy weather offshore handling, I cant comment. I use lazy jacks so the point is moot, however I defer to experience.

    What it comes down to is a personal choice, but a shell foot is more expensive and as previously mentioned you cant kick back in a 10 knot sea breeze with a beer in hand lying along a loose footed main( which about the only disadvantage I can see!)
     
  2. Silver Raven
    Joined: Oct 2011
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    Silver Raven Senior Member

    Hey there - pakia - "you can't kick back in a 10 knot sea breeze with a beer in hand lying along a loose footed main" ??? is that because 'T-W' 'Voom' - 'Stlth-Mis'in' plus 8 others - would just 'hose-you-down' or because you'd spill your beer (everyone knows that - spilling beer is a 'cardinal-sin') so no 'sailors-heaven' for you - K1-kid. I'd love to get PAR on a cat/tri on Ackland harbour - in a race - in 15 to 20 kts & see what he thinks of 'loose-footed mains. WOW - I'd like to be there also. ciao, james.
     
  3. motorbike
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    motorbike Senior Member

    James, I was out in a gusty 3 easterly up the harbour the other day, and frankly the last thing on my mind was shell foot vs loose foot. I had to crank on plenty of outhaul (which is 4:1 in boom) only by easing the sheet, otherwise impossible. Didnt notice the boom bend, nor any downdraft through the slot in the foot. I am pointing at the spot vacated by the crew who tried to drink beer lying along the boom.

    [​IMG]
     
  4. sean9c
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    sean9c Senior Member

    Big problem is that your jib sheets are backwards. Red should be on port side :)
     
  5. motorbike
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    motorbike Senior Member

    Ha! I didnt even notice, but I can blame the slimey swab Dave who rigged them that day.
     
  6. Paul B

    Paul B Previous Member

    Why don't you "prove" your claims?


    Sorry, incorrect.

    The load from the sail is not distributed along the boom. The load paths are exactly the same for an attached foot and a loose foot.

    Consider the good old days of the 1970s. We had not so stiff Dacron for our sail materials. We also had things like droopy booms and flattening reefs. In those days the boom would be allowed to droop offwind (supposedly increasing sail area) and upwind we would pull on the flat reef any time we had enough wind to have everyone on the rail. The flat reef basically pulled the clew back up to level. Well, with the flat reef in, guess what kind of mainsail we had? Yep it was, for all intents and purposes, a loose footed main. It was attached at the tack and at the flat reef clew, and nowhere in between.

    Then things got even crazier. The wind would increase and, lo and behold, we would reef. Let’s see, the reefed main was attached at the new tack and reef point clew!

    Oh my, the 80s came along. We had our “shelf mains”. With the outhaul “on”, the shelf would collapse between the sail and the boom. While it was attached along the foot there was loose material between the boom and the part of the sail that was under load. I wonder why the booms weren’t bending until the shelf was stretched taught and supporting some of the load?

    Actually, I don’t wonder about that. I know how to sail.


    Well there you have it. Some numbskull wrote something ridiculous and you believed it. Now you have written something ridiculous and some other numbskull will believe it. After all, it was written on the internet, so must be true.


    No. When the outhaul is pulled on, the foot round pretty much seals against the boom. So there is no more pressure loss than on an attached foot. In fact, there is probably less pressure loss than the old style of foot that used sliders instead of a bolt rope.

    Consider the hundreds of millions of dollars the top tier racing folk spend on their hobbies. If there was any data that showed an attached foot gave any more drive than a loose foot every racing sail would have an attached foot. I have not seen a race boat in about 25 years with an attached foot. Maybe there is a reason for this?


    Do I really have to comment on this nonsense?


    Of all the thousands (hundreds of thousands?) of boats that have replaced their old mains with loose footed mains, how many do you think have had to install “considerably stronger” outhauls? You obviously don’t understand the load paths of mainsails.

    On virtually every boomed mainsail the tack and clew attachment points are above the boom itself. So the tension of the outhaul is above the boom, in a direct line between the tack and clew. This is true whether the foot is attached or loose. The load is the same.


    Failure of the outhaul would not turn the sail into a flag.

    I’ve probably sailed on a hundred boats and in proximity of thousands of others with loose footed mains during the past 25 years. I have seen one (1) clew blow out. It was on a new, high tech carbon sail that had a construction issue. I’m sure there are others that I did not see, but the “problem” you are concerned about is statistically “in the noise”.


    Of course none of these facts will “prove” anything to you. Internet experts like you obviously know better than the people who make their living working these things out.
     
  7. Paul B

    Paul B Previous Member

    Oh my lord.

    Talk about making up some weird "failure mode" to support your weird claim.

    Can you tell us of all the boom failures from this sort of out-of-column comopression due to loose footed mains?
     
  8. Paul B

    Paul B Previous Member

    You shouldn't feel any need to defer. I suspect you have more experience with loose footed mains than he does, based on his "expert" comment.

    You will note he has provided no details about the handling issues, because there aren't any.

    In fact, if you are out in a blow offshore and need to get the main off and below while flying the trysail the loose footed sail is going to much easier to deal with. You can get it all controlled with sail ties before removing from the boom, and you can simply pull two pins and drop it right into the cockpit. Much better than having to go forward and pull the foot out of the boom, forward and between the mast and rigging.
     
  9. motorbike
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    motorbike Senior Member

    Yep its the ol internet expert syndrome alright! My experience having had both over many years is that a loose footed main is easier handle as you mention, and all the load bullcrap is just that, irrelevant nonsense. In the pic above its about 20kts on the wind the sea state is flat and so is the mainsail, there is virtually NO slot between the boom and sail which shows every thing youve said to be true.
    The warning signs are "scamp" "small craft advisor" and "bolger" no disrespect but when all these words are used in giving answers that are contrarian you can virtually guarantee its not coming from hands on experience.
     
  10. maxstaylock
    Joined: Jan 2012
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    maxstaylock Junior Member

    Mr Bieker, sir, you are a legend.

    When I started racing dinghies 25 years ago, there were still some boats around that used bendy booms with captive foots, and tight foots. They were mediocre, at best, any slight advantage from extra foot flattening, was overcome by an inability to accurately vang sheet, an inability to get the foot shape you need for full power beating and reaching, a pain to rig, and a greater propensity to break booms. RIP. Anybody who thinks loose footed sails are dangerous and inefficient, look at every boat and sail from the last quarter century. They can't all be wrong.

    One or two applications that confuse the issue, for me, I have also raced on some gaff cutters, where the boom length = the main luff length, if we took a jiffy reef, i.e. no reef pennants (hundreds of the basterds) tied in, the boom did take a bit more of a bend. And lateen rigs, effectively two lightweight spars, captive sails supported along their length. In both of these cases, a loose foot, would require a much heavier spar. Or the top spar of a Dhow. I am not saying that these rigs come within a mile of a modern high aspect rig, in performance or gear change ability. But is does seem with those rigs the spar/sail seem to have a more symbiotic relationship?

    I am not saying that the sail, in these cases, is supporting the spar. That would be ridiculous. But the spars can be lighter, because all the load of the sail is not transmitted directly to the clew end, i.e. half the tension of the middle of the sail, is supported by the middle of the spar, allowing more taper of the spar at the outer end?

    Thanks, just asking. I understand this is if no practical benefit to high aspect rigs.
     
  11. Doug Lord
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    Doug Lord Flight Ready

    ===================
    I can assure you Paul Bieker is NOT participating in this thread.....
     
  12. CutOnce

    CutOnce Previous Member

    Depending on which side the compass is actually mounted, it just could be a reversed photograph. Photographic lexdisia? Would not be the first time.

    --
    CutOnce
     
  13. Paul B

    Paul B Previous Member

    I don't know if this is in reference to me. If so, I am not Paul Bieker.

    However, if he was posting here I doubt he would be in disagreement with what I've written.

    I was Paul B before he was, and I am also a legend in some circles.
     

  14. Paul B

    Paul B Previous Member

    Oh no. You have besmirched the name many on this board worship. Woe is to you..

    even though you are right.
     
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