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Discussion Starter #1 (Edited)
I just finished and loved the account from Joshua Slocum about his solo circumnavigation; the worlds first:

Sailing Alone Around the World, by Joshua Slocum, 1900

It is a soulful and engaging story.

He was an exceptionally experienced master seaman. However, his repeated claim that his boat was so well balanced that he rarely stood helm, even at 8 knots, seems to me a testament to superior 19th century boat-building/rigging skills (his Spray), or (very fortunate) bad weather, which was ubiquitous throughout the journey.

Is a gale today what it was then? Are boats today less able to balance than his sloop back then? Did he indeed have a Spanish patron helmsman, or am I just too suspicious?

My best balancing of my 27', 5 ton full keel cutter is for a few hours or so in 15+ close wind, but I have to take care of my movements. Eventually an unusual swell or my moving about, or clocking wind knocks it a kilter and I scurry back to the helm.

Granted his boat was 36' on deck, carrying 46+, jib tack to mizzen clew (sprit and boomkin) and 12+ gross tons, but it wasn't very deep in its full keel. What gives?

And it's true he does, at various times in his odyssey, cut down mast, bowsprit and boom and also adds a yawl mizzen, but does none out of complaint of balance. In fact, without explanation, he modifies the sloop in these ways which, one would think, threatened its balance potential.

It seems to me that the difference between trim balance good for a few hours and trim balance good for days is either quantum mechanics, the boat/rig design, or the story teller.

Others are amazed at this steering achievement, as Slocum himself recounts.

What am I missing here?

What minuscule change does it take to make sail trim that's true and balanced for a few hours become trim able to stand up to a few days?

No B.S. please.;)
 

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This is a black art indeed, because so few boats are designed with self-tending helms in mind...it is simply not a priority as auto-pilots, other crew or windvanes can cope with the job.

I also think Slocum exaggerated his boat's "inherent qualities" a bit for effect. This is not in any way to take away from his achievements, which are many and spectacular, but to illustrate that he was quite consciously in a long line of seamen who probably thought a good tale was even more entertaining than the truth. I say this because the lines of the "Spray" (being one of the most famous in history thanks to Slocum's feats and claims) have been replicated many times to the present day (a Bruce Roberts design follows it closely), but no one to my knowledge has replicated the particular qualities of the original as praised by Slocum.

So I wouldn't obsess over it were I you. You will either discover "the sweet spot" particular to your own boat, or you will not. If Slocum did, it's because he wandered around the world at four knots and probably had ample time to experiment that we moderns aren't willing or able to put in. If you need 1 degree of weather helm, for instance, are you going to run a string from coaming to coaming so that the helm can be lashed in precisely that position, time after time? It's quite possible that Slocum did this, and more, in order to relieve himself of having to invent the wind vane.

Having said that, there are a great number of tips and techniques one can use to balance the helm via sail trim, and with a hefty full keeler, you've got a better chance than most to achieve them. If you can walk away from the helm for "a few hours" close reached in 15 knots, you may be at the limit of what you can expect. I have a full keel cutter at 15 tons and 41 feet LOA and I haven't had the hydraulic steering disengaged for enough time to see if I can self-steer half the day, but I have done so with my four and half ton ton 33 foot fin keeler...but I can't move around much without either throwing off the balance into a long curve to head-to-wind, or in waves over two feet, incurring a sudden rounding up if I move forward of the mast.

The key is to forget about completely untended self-steering entirely and to instead focus on very simple feedback systems to the tiller (sorry, but these ideas really like a tiller!). Probably the simplest is attaching the jib sheet to the tiller in conjunction with shock cord, aka "bungee cord". The best explanations I saw of this is in Tony Meisel's "Singlehanding: A Sailor's Guide" and his somewhat similar "Manual of Singlehanded Sailing"

SINGLEHANDING - A Sailor's Guide - By Tony Meisel - Hardback Book
Meisel, TonyA MANUAL OF SINGLEHANDED SAILING <meta name="description" content=" A MANUAL OF SINGLEHANDED SAILING ,  Meisel, Tony ">

These books are easily found used, and are very no-nonsense.
 

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A mizzen sail adds a lot of balance to the boat. A ful keel + mizzen mast combination with a good trim of the sails allows the boat to keep a steady course.

My boat is a wooden ketch designed by Thomas A Gillmer. I have an auto pilot which stays home because I am not using it anymore. A good sail trim and locking the tiller keeps the boat on route if you have a steady wind. In case you have too much changes in wind speed and direction you can change your direction with small changes to the mizzen sail trim.
 

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Another good book on singlehanded sailing is Singlehanded Sailing: The Experiences and Techniques of the Lone Voyagers, by Richard Henderson.
 

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A mizzen sail adds a lot of balance to the boat. A ful keel + mizzen mast combination with a good trim of the sails allows the boat to keep a steady course.

My boat is a wooden ketch designed by Thomas A Gillmer. I have an auto pilot which stays home because I am not using it anymore. A good sail trim and locking the tiller keeps the boat on route if you have a steady wind. In case you have too much changes in wind speed and direction you can change your direction with small changes to the mizzen sail trim.
I never could find sound enough reason to add a secon rig to my boat so I sail a sloop. In my experience, setting boat up to steer itself is easy enough on the wind (and I mean ON the wind, not even reaching). Setting up to autosteer without a pilot of some sort when running downwind cannot be done without some form of mechanical device, even if it is just lines and stuff connected to obscure parts of the rig.

I sailed single handed from just east of SriLanka to Christmas Island (Indian) i.e a few hundred miles over several days, with a broken auto-pilot and the boat set up to sail herself. A bungie cord on the wheel worked well once the boat tended to self-steer. But as soon as the wind went around even a bit, the boat had to be helmed.
 

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Slocum's Spray had such a long keel it must have been really difficult to make it turn. Maybe that's why he sailed around the world- he couldn't turn back??! Based on his use of a wind-up alarm clock for navigation, I can't think he considered swinging 20 or 30 degrees off a target course as being a problem. His compass probably wasn't marked in degrees, either: SouthWest x South would have been close enough.
 

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Discussion Starter #8
Valiente,

I don't know how I missed your excellent explanation to my, now, old post about Slocum's magical success at self steering stability. It has recently been re-activated and I now have re-read your response. It's first rate.:)

Among other things, you said:

"The key is to forget about completely untended self-steering entirely and to instead focus on very simple feedback systems to the tiller (sorry, but these ideas really like a tiller!). Probably the simplest is attaching the jib sheet to the tiller in conjunction with shock cord, aka "bungee cord". The best explanations I saw of this is in Tony Meisel's "Singlehanding: A Sailor's Guide" and his somewhat similar "Manual of Singlehanded Sailing"

SINGLEHANDING - A Sailor's Guide - By Tony Meisel - Hardback Book
Meisel, TonyA MANUAL OF SINGLEHANDED SAILING"

SD had another good book selection: Henderson. I will now look for the Meisel and Henderson books, thank you both.

I'm a year away from committing to a boat purchase. Which is to say I have all the time in the world to change my mind about type. One apple of my eye is the Cape George 36', which is a tiller. I'm more used to a wheel. However 25 years ago I did have a Montgomery 17' and now my yacht is a 10' Gig Harbor dink/sloop. How do I break the idea that tillers are for tenders?:confused:
 

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The modern cruising boat is set up for drinking and dining in a space smaller than the average picnic table (a cockpit) under shelter smaller than the average patio umbrella (a bimini). Frankly, I've had better meals on pointy rocks. The wheel plays into this by giving the illusion of six by four feet of empty space in front of the helmsperson (which makes the boat look bigger even as it puts the weight of a human at the far end of the boat), and by replicating the way a car steers, even if that is not a great model for a boat, because it is the FRONT wheels of a car that steer, not a single large wheel at the back.

Intriguingly, the very first autos of the 1890s sporting in some cases a tiller steering setup, with motive power at the front and a "trailing" steerable wheel at the back. A great deal of the history of car, airplane and boat design is, however, convention and prejudice, not good engineering, and I would say this is the case with wheel vs. tiller. Early small boat wheels, however, were meant to be steered "backwards" to today's set-up, in which the helmsman would stand in front of the wheel, which would be mounted angled up, and would treat it like a tiller with mechanical advantage.

While I would hesitate to work from the tiller outward in determining a boat purchase, some things to consider include why solo distance sailors favour the tiller. Some reasons are that the helmsman stays near the lines; the set-up is mechanically simple and arguably more robust due to fewer points of potential failure; you get "feel" from a tiller that is not available on a wheel that is either mechanically or hydraulically linked; you can make an emergency tiller out of a 2 x 4, or easily carry a spare; and lastly, because of the direct relationship between tiller angle, rudder angle and turning effect, you can rig up self-steering of appreciable subtlety and self-correcting ability. Standing with the tiller between my knees and two hands for the sheets, I feel very connected to all the forces on my boat, and I can "execute" very effectively various tack and gybes by myself, dinghy-fashion. And of course, if you aren't stuck behind a wheel, you can get off the boat and on the dock with a spring line very quickly, because nothing but a coaming and a toe-rail and a lifeline is in your way.

And if you want to eat crabs and drink beer in the cockpit, you can lash it vertically, or remove it with 10 seconds and a wrench. No wheel in the cockpit means more room.

Now, a Cape George 36 is a biggish boat for a tiller, but its transom-hung rudder and full keel make it ideal for tiller work. I don't see that being an issue unless you are a particularly small person. A tiller is, of course, a lever, and even in heavy seas, a longer tiller or an extension will make whatever force you apply with muscle multiply at the end of the rudder, where the steering happens. I customarily steer with my legs, either from handling the main and shifting my hips (I'll leave the visual to you!), or from steering with my feet from the high side while handling the weather sheet around a winch. Sometimes on a long tack I will use the extender, and the force on it a baby could handle, once the trim is right.

I hope this helps.
 

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With regards to Slocum and Spray's self-steering, Sprays rig was very long relative to the length of the boat and broken into smallish parts. It is the sail plan equivlient of a very full length keel. Descriptions by independent observers who got to sail on Spray describe her as very slow in stays and as having variously weather or lee helm and suggest that Slocum was able to over trim either the headstaysail or mizzen to balance the helm to the conditions. Slocum is described as using a handy-billy (block and tackle) on the helm at times which suggests anything but a ballanced helm. And as has been noted, Slocum's offshore course keeping was less than perfectly precise, and his passage times less than stellar even for that day and boat size.

The issue of balance and tracking is a complex one. The length of the keel really plays a very small part in the ability of the boat to track under sail. The theory behind a long keel having better directional stability is that it has a large polar moment of inertia. That large moment of inertic only occurs statically and in very low speed sitations. In reality much of the length of a full keel is stalled out and exposed to large amounts of turbulance that undermines the keel's ability to resist changes in course. Modern fin keel boats, which often have their keels very far forward and their rudders very far aft often develop similar or even greater polar moments of inertia. When you add the high polar moment of inertia that comes from a modern boat's hull form with its fine bow and moderately narrow sailing plane, vs the comparatively stubby hull forms employed by more traditional heavy displacement designs, you can see why modern boats often inherently better lighter helms and better directional stability. This makes them better suited to operating under some form of vane steering.

Which brings us to the second point, most small boats track best when a dynamic balance between the rig and the under water appendages can be achieved. For the most part the key is for the boat have a relatively balanced hull form, and a rig that is dynamically balanced with the hull. The better modern boat designs are capable of being dynamically balanced with their sails properly trimmed for performance. On traditional rigs, it was not unusual to overtrim a headsail to help balance the helm at the price of greater heeling and loss of performance.

Which comes to my final point, traditional keel hung rudders, by their very nature develop large amounts of weather helm on all points of sail except for dead down wind. This is because of the force that is occurs on any under water appendage when beating or reaching and the relationship of that side force to the hinge point of a keel hung rudder. To offset that force, the dynamic turning forces of the heeled hull, and trim of the sails need to be such as to produce lee helm, which then balances the helms natural tendancy to produce weather helm. This relationship, by its very nature, means that heel angle and windspeed play a major role in the course sailed by the boat and that course keeping is much harder in varying windspeeds such as would be found between the crest of a large wave and its trough.

Jeff
 

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A good analysis, Jeff. Everything I've read, plus everything I've attempted on two rather different boats, suggests that you must trim the sails to the keel, so to speak, to achieve a balance of forces if you wish to have as "natural", by which I mean unforced, a circumstance for self-steering as possible.

This suggests that self-steering without external aids, such as windvanes, is in fact possible on most boats, but not on all points of sail and not in all conditions of sea and wind, and at times at a cost to sailing efficiency and even comfort/seakindliness.

In this sense, it seems to be a mirror of the ability of various boats to heave-to effectively.
 
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