Weather Helm on IOR Ranger 37 - Rudder Modifications?

Discussion in 'Sailboats' started by RangerOneTon, Jul 8, 2022.

  1. Will Gilmore
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    Will Gilmore Senior Member

    The changes gonzo is taking about would cost no money, unless you don't already have a smaller headsail.

    If you still suffer extreme weather helm under genny only, it may not move you CE forward enough with the reefed main, but it should allow you to discover your best CE location. Then work from there.

    I look at the line drawing of your boat posted by bajansailor and I estimate the CE, under the Genoa shown, to be somewhere just ahead of the mast. Without heel, the CLR looks to be around a line down from where the back of the fin connects with the hull. Those things don't look too bad. I imagine that when she's heeled, much of the rudder skeg disappears from the profile because of the wide midship lines at the waterline and those finely tapered ends. Her bow will go down with that tall mast and headsail design.

    By reefing, you lower your CE, as well as move it forward, and you don't stuff the bow as much.

    If she sails well enough under a smaller headsail and reefed main, you might simply convert her to a fractional rig and cut you main down a little.
     
    Last edited: Jul 18, 2022
  2. CT249
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    CT249 Senior Member

    The Ranger 37 wouldn't have been a winner (which it was) with that much weather helm. I've got a pic of the famous R37 Munequita charging upwind with #3 headsail, one reef, and absolutely perfect balance; the tiller is almost dead straight.

    Assuming your boat is unmodified, to be honest you may be heeling too much and/or oversheeting. Those cause more weather helm than anything to do with design.
     
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  3. Flotation
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    Flotation Senior Member

    How old is that genoa? If it's really old and baggy that could contribute a lot to weather helm. As would lack of headstay tension and/or halyard tension.
     
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  4. RangerOneTon
    Joined: Jul 2022
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    Location: Caribbean

    RangerOneTon New Member

    Thanks so much to all!! So great to have all these brains in one place... I am especially interested in where the weight would be of most use, Of course I would prefer some hefty bodies on the rail, but alas all I have to work with is 20 gallons of jerry cans of water, and the general placement of stuff below.

    In response to the many questions and suggestions:

    - It has the original small rudder, with what looks like a half skeg connection, in front of this I epoxied a small piece of plastic to keep lines and nets out from between the gap.. Maybe this is causing a hydraulic swirl that looses some of the rudder efficiency?

    -Yes the boat is weighted down with 50m of chain and an anchor up front, 40 gallons of water amidships, It is challenging to get the forestay bar tight,

    - It does steer better when flat, but even on a very broad reach with the genoa poled out it has the tendency to pull hard on the tiller.

    - The Genoa is quite worn and not at all flat, but there is a solent sail I use in over 15kts going upwind that is flatter, with that and a second reefed main
    it has moderate weather helm.

    -There is no traveller, for lightwind I haul the boom straight with a secondary line.

    Thanks again, any one have any access to later rudder desgns??

    -
     
  5. sharpii2
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    sharpii2 Senior Member

    A possible cheap solution would be to move as much cruising gear as possible to the stern of the boat. You might even try adding removable ballast there. I'd try using jugs of drinking water first, then maybe some sand bags later, if the jugs aren't enough.

    Reefing early and often would also help. I'd reef the main before even thinking about the jib. But the Genoa would be the first to go.

    For hull modifications, I'd increase the size of the skeg before I'd consider doing anything else.
     
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  6. jehardiman
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    jehardiman Senior Member

    I doubt that would work with the IOR III pinched stern. It would make the round up/weather helm worse. As I said before, weight out of the stern makers them sail better...IOR III boats like to be sailed flat and level with reefing early and often.
     
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  7. gonzo
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    gonzo Senior Member

    From my old days of racing them, 12 degrees was the max before shortening sail.
     
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  8. sharpii2
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    sharpii2 Senior Member

    How many crew would such a boat as a "one-tonner" typically have. Was it around a dozen?
     
  9. sharpii2
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    sharpii2 Senior Member

    I guess this makes some sense, as the sharp curve of the higher waterlines would suck the wake back toward the centerline. The reaction of this would be to turn the boat upwind.

    Would extending the skeg forward, to nearly double its area, help enough to be worth it?

    Or would doing this cause too much of a lee helm, while the boat is sailing upright?
     
  10. jehardiman
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    jehardiman Senior Member

    The Santana 37 I used to sail on it was 8-10; 3 in the afterguard (helm, main, & tailer), bowman, and 4-6 grinders/rail meat. Grinder only came off the rail in the tacks, bowman on the rail when not working.
     
  11. gonzo
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    gonzo Senior Member

    Probably. They would choose the rail meat by their weight. Fat guys on windy days ;)
     
  12. rnlock
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    rnlock Senior Member

    These suggestions probably won't be useful, but if you really feel the need for expensive modification:
    -Get rid of that ugly spinning thing and fill in that space. A longer skeg might help, too, but now we're talking about more serious engineering.
    -Add wings to the keel. I think that would increase the lift down low. Since the fin is swept, that moves the "lateral resistance" back. It might not need very much structural engineering, but it would probably work out best if you consulted a hydrodynamics expert.

    However, the first thing to do might be to compare your boat to others of the same design to see if anything's different about yours.
     
  13. gonzo
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    gonzo Senior Member

    It behaves like the IOR designs of the era. They were known to broach and nose-dive.
     
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  14. KeithO
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    KeithO Senior Member


  15. jehardiman
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    jehardiman Senior Member

    Yep.
    Ranger One Ton; you need to focus on the fact that IOR boats of that era are not about balanced underwater shapes that make a good single hander. They were all about hitting the "right" girths and proportions to garner a particular rating while maximizing LWL and sail carrying ability above the measured SA.
    I said earlier that I sailed on a Santana 37, it was actually not... it was a "Santana 39" which was a 37 with an added non-structural "sugar scoop" and "IOR blisters" just to get the rating. When I raced it, it had an old age allowance and a Kevlar/Mylar suit of sail and aramid lines which was eating the boat up.

    Edit: Besides Gary Mull, look up the boats of Doug Peterson, particularly Louisiana Crude and Scarlett
     
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