Galion 22 conversion

  • 13 Jul 2018 19:41
    Reply # 6380471 on 5070195

    There's no hook to the leech, so that's good. I can see broad seam and then a tuck in the forward part of the sail, indicating that most of the depth of camber is here, and then a seam with no broadseaming about halfway aft. Also, the shadows are not telling me that there is too much curvature aft, in the horizontal plane. So I think that your weather helm is not due to the shaping of the sail. I suspected an ineffective rudder that is too far forward - but no, looking at sailboatdata.com I don't see anything wrong with the rudder.

    Last modified: 13 Jul 2018 19:46 | Anonymous member
  • 13 Jul 2018 18:28
    Reply # 6380373 on 5070195
    Thanks, Arne and David - I will consider Arne's points.

    What I'm afraid of is that excessive balance makes the mast and mast lift eat the "sweet spot" of the camber.

    David, does this photo give any hint of the sail shape questions you pointed out? (Very light wind explains most of the wrinkles and the slingpoint has slipped quite a lot aft by a mistake)

    1 file
    Last modified: 13 Jul 2018 18:29 | Anonymous member
  • 13 Jul 2018 13:10
    Reply # 6379939 on 5070195

    Jami, excessive weather helm is often caused by having too much camber in the sail, too far aft. A hooked leech is another thing to look for. The panels should have little or no curvature from the 60% point, aft to the leech.

  • 13 Jul 2018 10:31
    Reply # 6379868 on 5070195
    Anonymous member (Administrator)

    Funny that, Jami!

    Making a new rudder is quite a job. I was involved in designing, and partly building a new rudder for an Athena 34 this spring (the old rudder suddenly parted with the boat). That was a success, but it took quite some work.

    However, before setting off on such a project, I have a number of comments and questions:

    ·         How did the Gallion 22 balance with the Bermuda rig? The CE of the JR is not aft of that of the original rig.

    ·         With weather helm, do you mean big rudder angle or just high tiller forces? The rudder appears to have a bit balance built into it, but not much.

    ·         I have drawn the JR in its aft position, i.e. with minimum balance (10%). If the slingpoint on the yard is moved to 5% aft of the middle, the sail can be shifted forward to 15 or even 17-18% balance  -  that is  -  if the batten parrels have been made long enough. It takes less work to fix the batten parrels than making a new rudder. I was initially sceptical to have a cambered sail with this much balance, but Paul Thompson has proven that it works well on his La Chica, so I have stopped nagging about keeping the balance to a minimum.

    Hardly any boat have so neutral helm that one can sail with the tiller free. One factor that prevents this is that more than half of modern boats are not directionally stable. You can check the latter this way:

    ·         On a calm day, motor at full speed in a straight line.

    ·         Then, stop the engine ( the best would be if it was swung up) and push the tiller moderately over to start a swing.

    ·         Take your hands off the tiller and see what happens.

    ·         If the boat’s swing gradually stops and the boat takes a straight course, then she is course stable.

    ·         If the boat keeps turning or even goes into a sharper and sharper turn, then it is directionally unstable. Such a boat will need a sort of tiller lock even if you manage to get the CE to CLR distance right.

    That big Athena 34 I mentioned was not directionally stable, so has recently been given a tiller lock to let the skipper tend to the sheets, now and then, without the boat going into a mad turn.

    Cheers, Arne


    Last modified: 13 Jul 2018 10:50 | Anonymous member (Administrator)
  • 13 Jul 2018 07:45
    Reply # 6379689 on 5070195
    Tweaking, fine-tuning, learning and enjoying!

    However, I don't seem to get rid of the strong weather helm issue. I have moved the sail forward (now about 10% overlap, and the mast is quite far forward), but for some reason the weather helm is still stronger than I would like. The helm cannot be left alone at all

    It seems like a transom-hung rudder project next winter. Any help with the design is highly appreciated.

  • 07 Jul 2018 20:08
    Reply # 6364567 on 5070195

    I agree, Arne, the angles and speed are as much as I'd expect from this size and type of boat. I only get better than 4.5 kn in absolutely idea conditions.

  • 04 Jul 2018 22:24
    Reply # 6360704 on 5070195
    Anonymous member (Administrator)

    Jami,
    now I looked up Gallions 22's data on the web. With her short waterline and shallow draught, I wouldn't expect her to go any faster, or point any higher with a Bermuda rig. In fact, I wonder if the JR is not making her better…

    Arne

  • 03 Jul 2018 15:21
    Reply # 6358287 on 5070195
    Still tweaking and wondering happily :)

    What would you say about the pictures below, regarding windward performance/course? Not bad - but nothing special, either?

    Force 4-5, boat speed 3.5-4.5 knots.

    (What surprised me was that the speed remained unchanged, when I turned back and saild dead downwind with the same sail area.)


    3 files
    Last modified: 03 Jul 2018 15:22 | Anonymous member
  • 22 Jun 2018 16:24
    Reply # 6332934 on 6332637
    Anonymous wrote:

    On this latest video, I can see that the span at the bottom of the topping lifts is not capturing the reefed sail very well, and the after attachment needs to be further aft.

    Indeed - but they are still temporary; I am making a sail catcher, but my sewing machine broke before it was finished.
  • 22 Jun 2018 14:34
    Reply # 6332637 on 5070195

    On this latest video, I can see that the span at the bottom of the topping lifts is not capturing the reefed sail very well, and the after attachment needs to be further aft.

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