Figure

correct diameter to take the thread on the pipe for a perfect fit, tight enough to allow no working or leakage. (We put bolts horizontally through the timber, above the planking both forward and aft of the port, to guard against any split that might develop.) We used this simple system on dozens of boats, with the approval of the designers and our own consciences, and with no catastrophic failures, but we finally chose a more complicated arrangement—a custom-made casting to fit each particular boat, which was better in several ways. As shown in Figure 19-3, this is a heavy casting, with a wide base, angled to bolt on top of the tail feather, and fitted with a packing gland. This casting provides a stronger support for the rudder stock, and can always be re-seated if any leak develops under its flanged base. (It's a very pretty piece of pat tern ma king, too, and fine practice for the work you'll be doing someday on goosenecks and hawsepipes.)

You'll core for the hole, and clean the casting itself out to a smooth clearance for the rudder stock; and you'll wait, for the final fitting and bolting, until you've swung the rudder into place (having, of course, lined the rudder port with copper tube or lead sleeve, and the grooved stern post with sheet copper.) Drop the lovely casting down over the stock, shave the top of the horn timber (tail feather) to correct for any tiny errors in angle, and fasten it down—preferably with naval bronze bolts, to match the metal in the casting. And I mean bolts, four of them, all the way through the tail feather. Bronze screws are not good enough. I've seen one of these castings, screw-fastened, all adrift and leaking torrents, and the boat was onlv 40 years old.

Two more warnings. First, the heel of the rudder must sit tightly upon an extension of the deadwood, or in some sort of heel bearing, with no gap to catch your overridden anchorline or a lobster-pot warp. Second, the stock should, if possible, extend upward through a strong bearing at the deck, with an exposed fitting to take an emergency tiller. This upper bearing helps to withstand the severe side-load generated by the lever arm of the steering device working against the pressure of the rudder—and note that the load approaches infinity as the tiller length approaches zero. This sounds like a desperate way to describe the situation. Your knowledgeable friends will point out, patiently, that the torque on the rudder head remains constant, whatever the length of the lever arm, and that a hydraulic ram with a 100-pound thrust against a 1-inch tiller has the same turning effect (torque) as a 1-pound thrust on a 100-inch tiller—or words to that effect. But these experts always ignore the side-thrust, which is the cause of much rudder trouble. Therefore, if you choose a worm-screw steerer (and a very good choice it is, if you can find one), get the double-arm style, as shown in Figure 19-4. If you can grab the brat by both ears, you can twist its neck without breaking it off. That hydraulic ram looks like a perfect solution, but its power must be countered by strong bearings, above and below, or it can wring the stern right off.

An outboard rudder

I trust that the above has put you in a proper frame of mind to appreciate the other kind of rudder—hung outdoors for all to see, vulnerable to attack by pirates, and terminating the length of the vessel in a no-nonsense lack of overhang. There are some (myself among them) who feel that after overhang in a vessel is worth its cost and weight when that vessel is running downwind in a big following sea; but. that is a mat ter of opinion only, and fares poorly against the obvious and numerous virtues of the sawn-off stern and its outboard rudder: No holes through the hull; a cinch for a self-steering-setup; cheap, strong, all-wood construction. Beauty is, after all, in the eye of the beholder, and most of the present-day beholders are too young to have been corrupted by the seductions of ancient classics; so let's get at it, and build an outboard rudder. (See Figure 19-5.)

Begin with the technique as described for the inboard rudder, first making a skeleton pattern from a thin board for the main piece, marked with the line of shaft, the propeller aperture, the top of the transom, the location of the pintles, the angle of the bottom in profile. Now find the best piece of oak that ever grew on the cold hillside—a plank sawn from near the center of the butt log, blue in color, with interlocked grain and a tough, mean look about it.. Joint one edge of this plank absolutely straight, and lay it in, waiting until you've installed the gudgeons on the transom and the sternpost.

Hanging the rudder (outboard)

It's unlikely that vou can locate off-the-shelf

hardware for hanging this rudder, so you'll do well to make patterns and get castings before proceeding any further. Note that the gudgeons on (hesternpost are one-piececastings, and that one pattern will do for all three—the upper one, shorter in the arms and wider in the spread, can he bent wider and sawn shorter. (If the bronze won t stand that much bend, you'd better take the whole batch back to the foundry, and demand something better. Your rudder hardware must be above reproach.)

The fitting high on the transom must obviously have a flat base, to take bolts fore-and-aft through the transom knee; the other three are lei into the sternpost, above and below the propeller aperture and at the lower end of the post, and riveted through with Va-inch copper. And bear in mind, while you are fitting these, that one slight misalignment will lead to strained fastenings, worn bearings, noise, and the expenditure of about 50,000 unnecessary footpounds of energy over the next SO years. So take care, and get them in line. Install the top and bottom gudgeons, and align the others to a tight string between centers; or, easiest of all. use a length of cold-rolled steel shaft (borrowed, of course, and perfectly straight) to work to, for the final, delicate fitting.

All you need to do now is line up and rivet the pintles on the rudder, to match the gudgeon spacing; cut the aperture for the propeller, if any; fit the cheek pieces at the top, to take the tiller; and shape, drill, and drift the second (aft) piece to this main one. Taper this trailing edge of the rudder blade as much as you dare, so that the wake will close in around it, slick as off a mackerel's tail. (Many years ago I was told, separately and at length, by two of the most revered of all authorities, that this after edge should be left thick and square. One of the sages claimed that those bubbles and swirls were actually pushing the boat ahead; the other maintained that this area of confused currents increased the turning effect of the rudder to the extern of doubling its area. I delved into the theory of perpetual motion to strengthen my distrust of the first sage; and I eventually added another tapered plank to the rudder designed by the second that seemed, somehow, to lack authority in the likelihood of having to coax the vessel onto the other tack. I won't tell vou the names of these two, lest I be scourged to a dungeon by you who worship the True Word. But I advise you to make that blade big enough, and taper it down very thin.)

That cleat on the bottom edge may look somewhat amateurish, but it covers end grain, and helps wonderfully to withstand warping.

The tiller

And now, to control this outboard rudder: the simplest, cheapest, strongest, and most reliable means is a tiller (the longer, the better) that comes inboard above the top of the transom. It need not allow lor swinging more than 40 degrees from center amid sheet blocks and gallows frames, and it should fetch up against a positive stop when hard over. You can add controls 10 it in a dozen different wavs—lines on tackles from both sides, with quick-jam locking devices on lhem; or a notched comb, as in the old lobster sloops; or removable pegs in a crossbar, to stop fhe swing (and never in exactly the right place)—and even that wonderful system, unbelievable, called the Shin Cracker (described by Frank Bullen in Cruise of the Cachalot, incidentally) which mounted a steering wheel, with drum, on the end of the tiller, and wound itself back and forth across the deck like a spider trying to make up its mind. The helmsman got a peek ai the compass whenever his travels brought him past it. (Bullen's initial horror, I'm happy to state, softened to a grudging admiration for the svstem before the cruise was t long underway.)

Let's suppose, now, that your design (or desire) calls for conventional wheel steering, with stub tiller or quadrant entering through, rather than over, the transom. A quadrant, whether grooved for cable or toothed for gear, will fetch up against the inside of the transom when hard over, and make you wish it would go another 10 degrees. A straight tiller (plenty long, to keep low the strains on cable and rudderhead) can be arranged to give you an easy 40 degrees or more, and still fetch up against a positive stop clear of the transom; but you will have to accept uneven tension on the cables as the tiller goes from center to hard over. This effect is not as bad as it may sound; we've done dozens of rigs like this over the years, and they all worked. Inevitably, cables wore out and broke, and we learned the hard way that the finest stainless steel is the least durable material for steering cables. Plain steel, well greased, seems to last twice as long. Bronze tiller rope, if you can find it, is belter yet—and then, there's chain, and hard-laid Dacron. Design the parts of this system to give you at least three revolutions of the wheel from hard over to hard over, and be sure that you've provided for quick attachment of your emergency tiller, and have done something to bar insects and wavetops from entering your vessel through that tiller

Rudder bearings (inboard)

Pipe cap drilled to receive rudder stock

Flax packing

Good

Better

Bronze casting tapped to receive the nipple

Athwartshi bolts

Lined with copper tube

Sternpost hollow lined with sheet copper

Red brass pipe threaded directly through the tail feather

Two-piece casting above the propeller aperture (one pattern)

One-piece castings below the propeller aperture slot. We have used a rubber lube, seized around the inner neck of the tiller, and fastened tight to the circumference of the transom opening. An inner tube out of a truck tire (if there is yet such a thing available) does very nicely, and endures the flexing for a long time.

And, finally, this warning: Ignore the advice of those who tell you to install all these sheaves, cables, and push-rods while they are easy to get at, with no deck and cockpit in the way. That is bad thinking. Some distant day, a sheave will figure 19-4 Worm-screw steerers

Thrust collar bearing, aft (forward bearing is omitted) Double arm

(opposed threads)

There is no side load when both ears are twisted.

countered with a strong rudder-stock bearing at the deck.

Wedge-shaped keys in squared channels allow the one-piece collar to be driven upward for removal,

Twisting one ear puts a heavy side load on the free-standing rudder stock.

Single arm (continuous thread)

emergency tiller figure 19-5 Outboard rudder

Wood

Head block

Wood aperture

Cleat

Lock blocks

Head block

Cheek pieces (riveted through)

Cleat

Lock blocks

Wood

Wood

Gudgeon (let flush)

Pintle (let flush)

aperture freeze, or a cable break, or a key wiggle loose, and you'll have to crawl in and repair the damage, before you get blown onto a lee shore. When that day comes, you'll be glad you planned and installed these parts, originally, wilh everything in the way. If you did it once, you can do it again; but if you did it the sensible way, with the hull wide open, and then buried your steering installation behind handy shelves and impregnable bulkheads, you'll be sorry indeed. In the meantime, plan everything so that it can't possibly break, or corrode, or jam. Grease those sheaves, check the cables, and be sure the ash tiller hasn't rotted at the rudder-head. Should have been black locust, anyway. Happy steering to you.

Tbols

Chapter Twenty

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