Galion 22 conversion

  • 03 Jan 2019 20:38
    Reply # 6982195 on 5070195

    Jami,

    A trim tab's only advantage is that the vane can be smaller. Otherwise, it has disadvantages - it subtracts from the force of the rudder it's powering, so that rudder has to be bigger; it provides no active yaw resistance, unlike the pendulum. It's more complex than a simple vane-to-aux rudder gear, as complex as a pendulum.

    If you want to go for an auxiliary rudder, instead of a pendulum, have a good look at the Hydrovane, which now has a 50 year successful history, and is well respected by voyagers, including Jean-Luc Van Den Heede. See if you can understand the mechanism from the photos. That's difficult, and you won't be able to duplicate it, but look at the general principles. They deliberately don't give too much away in the photos, but it's something like this: A vane which is a cloth-covered frame on an axis inclined at about 15˚ to the horizontal. A vertical push-pull rod. A mechanism to change the vertical motion to rotational motion of the rudder shaft. A rudder that is one third to one half the area of the main rudder, with a balance of about 15%.

    What you should be able to manage is a vane with a 15˚ inclined axis, with a drum and a cord drive coming down, out to the corners of the transom and then back to a tiller on a dinghy-style rudder, half the size of your main rudder, with 15% balance, mounted on the transom. You should be able to copy the vane of my pendulum gear.

    You may or may not find this easier to make than my pendulum gear, but there won't be much difference. Either should give good steering.

  • 03 Jan 2019 12:59
    Reply # 6981379 on 5070195

    Arne,

    you made this effort again for me - this is superb altruistic service, thank you. I hope I can help this community somehow myself to pay back all the help I've had.

    I was thinking a trim tab on the rudder.

    Last modified: 03 Jan 2019 14:20 | Anonymous member
  • 03 Jan 2019 12:46
    Reply # 6981374 on 5070195
    Anonymous member (Administrator)

    Jami,

    I like your idea of shrinking the suggested transom hung rudder into an AUX. rudder for windvane use.
    On the sketch below I have drawn in the smaller rudder in blue.  Note how the balance (in %) has been increased to almost 22% to let a large hor.-axis windvane control it directly. The Bill Belcher OGT MkII would be my choice. That model struggled a little with driving my Albin Viggen's rudder, but that rudder was un-balanced. Your setup would be much more windvane-friendly.

    Arne


    Last modified: 28 Aug 2019 21:54 | Anonymous member (Administrator)
  • 02 Jan 2019 14:29
    Reply # 6979769 on 5070195

    Phew,
    it's been quite a while since the last time. The boat has been safely on my yard since late October, and now it's time to plan next season.

    One of the biggest issues still haunting my mind is the weather helm/stability issue, especially together with wind vane planning.

    Earlier (see below) we have discussed about a new rudder, to which Arne has graciously even drawn plans for.

    I was going to build a self steering system according to David's excellent plans.

    Then again, could I have two flies with one hit? What would you say about a smaller auxiliary rudder and a trim-tab or direct wind vane steering this with the main rudder locked? This should fix the weather helm, add directional stability and work as a self steering system (with all the cons of an aux-rudder self steering), right?

    (edit: not to mention a lot less work than a new, full-size rudder and a separate self steering system would need)

    Last modified: 03 Jan 2019 11:13 | Anonymous member
  • 14 Sep 2018 16:39
    Reply # 6669194 on 5070195
    Anonymous member (Administrator)

    Jami,

    The best yard angle is mainly a function of required balance of the sail. As said, my hunch is that your felt improvement stems from moving the sail forward, as well as reducing area. 

    If you try with the top panel again, and then shift the sail as far forward as you can, how does the helm balance end up? Remember, a ten degree, or even just a five degree rudder angle is not good for the speed.

    My own experience with the three top panels with 70deg. yard, has been very good, both on my present Ingeborg, and on the much more tender Frøken Sørensen.

    Arne


  • 14 Sep 2018 15:56
    Reply # 6669091 on 5070195

    Yep,

    But I wish I could get the same sailing quality with the top panel. It looks so much nicer.

  • 14 Sep 2018 15:41
    Reply # 6669056 on 5070195
    Anonymous member (Administrator)

    When I turbo-charges Malena’s flat sail in 1991 by fitting hinged battens and 10% camber, I soon found the boat to be over-rigged. Before next season, I had permanently rolled up the lowest panel, and the mast was cut down from 9.7 to 8.7m. In addition, the solid spruce pole was planed down 1-2cm (diameter). This turned out to be a big improvement.

    In those early days I had no experience with un-stayed masts, so I bet the first version was about 80kg, which was 5.7% of Malena’s displacement. The mast of Ingeborg is less than 2.5% of her displacement  -  so I must have learnt a bit since then.

    My guess is that when you have sailed for a while with the top panel removed (SA reduced from 27.3 to 23.0sqm), and with the sail shifted a bit forward, you will like it, and then you can shorten the mast as well, which will improve the boat as it did on my Malena.

    Arne


  • 14 Sep 2018 11:18
    Reply # 6668823 on 5070195

    Just out of curiosity, if nothing else, you can see a live feed video I did yesterday to Facebook (I think the video can be seen even if you are not a Facebook-user). The sail isn't properly visible, but eg from 7:00-> you (or at least I) can feel the good drive against the wind and swell, that I hadn't experienced with the JR on the Galion before this. Now it reminded me of the good headwind drive of the BR from last year! I think I have four panels up here.

    Last modified: 14 Sep 2018 19:37 | Anonymous member
  • 14 Sep 2018 10:57
    Reply # 6668805 on 5070195

    More testing is to follow.

    Regarding reefing, I compared the drive with four panels (ie 1-4)  in the original sail and four  panels (2-5) on the experimental one, so no difference in the SA.

  • 14 Sep 2018 10:42
    Reply # 6668800 on 5070195

    Jami, you recently changed to upper and lower sheeting. I wonder if now you have enough pull on the upper part of the sail to oversheet it? As I said here,  I find that at full sail, I need less tension on the upper sheet. The best way to check this is with leech telltales - about half a metre of ribbon at the ends of the yard and upper battens. They should all stream aft, and if they are collapsing behind the sail, then the upper sheet should be eased. Yes, more balance = less helm load, but there should be no effect on the lift/drag ratio.

    But you're talking about 16 - 20 knots of wind, and if your sail is just too big for the boat, and you're not reefing very much of it, could it just be the case that you're over-pressing the boat, and as is usually the case, when you take another reef, you go faster?

    Having said that, I wonder whether you're also simply experiencing the same feeling as I get with Weaverbird's sail, that the lower angle of the yard (subjectively, if not objectively) just makes everything seem easier? Anyway, as Arne says, if it works to take the top panel off, then go for it - after, of course, testing in as many conditions and over as long a period as you can. Do nothing too hastily.

       " ...there is nothing - absolutely nothing - half so much worth doing as simply messing about in junk-rigged boats" 
                                                               - the Chinese Water Rat

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