Rudder pattern (inboard)

Centerline shaft


Tail feather

Rudder port test batten (now strongback for rudder pattern; see Figure 6-2d)

Tail feather

Centerline shaft

Angle to bend the rudder stock


you clamp it atop something solid, with the short end overhanging the edge of the platform. Arrange a slop to catch the end when it droops to I he proper angle, and proceed to heal it at the bending point with a big, blue flame from your borrowed torch. Mind not the color of the heat, nor grow impatient and doubting. Maybe apply a very light pressure out on the end, and wait until it droops gently of its own sweet will, and stops just where you planned. Leave it to cool. Drill it precisely fore-and-aft for the Winch bolts. (This is best done on a drill press, of course, and the holes will require some tapered reaming and countersinking to take the forged heads of the bolts.) You will rejoice at the thought that the dogleg in this rudder stock handles the main part of the turning load, and the bolts are thus relieved of a great deal of stress.

The blade itself

So now we need a blade to wave behind this stock. I have always shaped this of wood, usually in twro pieces—(he main part fitted precisely to the bronze stock, and the after piece drifted to it, tapering to a fine edge aft. That's a simple proposition, but some care is needed in the selection and shaping of that w-ood. If you have had to cope with a few warped rudders, you'll understand the problem—which arises from wood's tendency to change shape with every change in moisture content. It is therefore reasonable to suggest that the wood, when shaped, should be as wet as wet can be, because that's how Old Ocean will keep it. You don't want something "perfectly seasoned"; you want, if possible, a piece from the middle of the log, with the annual rings square across it. You may also want to install a cleat on the bottom—and two sets of flat bronze bands, through-riveted, if all else fails. You must, of course, groove the rudder's forward edge to accept almost half the diameter of the stock in a light-tight fit, and then drill dead-center for the Dolts.

(It might be worthwhile at this point to consider what happens if this rudder can be made without the bend in the stock—for a boat with an off-center propeller, Herreshoff style, or for no propeller at all. This pleasant state would seem to allow a simpler, more efficient rudder; but its strength would depend almost entirely on the edge-bolts' resistance to bending, without the great power of that crooked stock to apply pressure to the blade.)

Hanging the rudder (inboard)

Let's assume that you've boiled the main (forward) piece of the rudder blade to the stock, as in Figure 19-2, and are ready to hang (or hinge) this rudder in place. I like to support it on four bearings: a stuffing-box of some sort on top of the tail feather, one bearing above the propeller aperture, and two more below it— with the bottom bearing as low as possible. To you who have gazed long at modern spade rudder s, this may seem a needless excess of good bronze castings; but I will not begrudge the extra cost. Look at Figure 19-3, and prepare to make the patterns.

The bearing above the propeller aperture must fit, of course, around the main stock, and must be such that vou can install it with the

rudder in place—and, incidentally, remove it with no great trouble in case of damage. The great Nat Herreshoff used a two-piece fitting, riveted together and to the stern post. I have meeklv and thankfully used the same device

since I first encountered it on a Herreshoff boat, and have not known it to fail or even wear to a sloppy fit. One pattern, of course, will do the two halves. Use Vs-inch hardened copper rivets through the sternpost, with perhaps a Winch-bronze rivet where the two halves come together.

And as for the bearings below the propeller aperture: I use one-piece castings, as shown, on the sternpost, with long straps let in flush and through-riveted. The mating half, on the rudder, slides in and is secured by the floating pin. (I assume that you can handle the simple patternmaking involved, and I hope that your foundry will pour good, old reliable naval bronze, which will bend, and stretch, and hang in there long after the super metals have perished from an excess of strength.)

Let's go clear to the top, now, and arrange for the stock to lodge inside the boat. This requires a hole through the tail feather that is aimed exactly down the line of the sternpost, and had best be lined with everlasting metal to keep the worms out. (They love dark, unpainted rudder-stock holes.) We usually achieved this ideal by boring for a threaded-pipe rudder port, of best red brass, screwed down through the timber. The right clearance for our standard 1 Winch-diameter rudder stock was provided by 1 Winch I.D. pipe, and a pipe cap, drilled out to shaft size, served to jam flax packing around the top of the stock to keep the port watertight. This installation required some precise work—boring a hole exactly in line, of

Rudder assembly (inboard)

Counterbored for carriage or stove-bolt head (to be filed smooth)

All fastenings are laid out on the plank stock before any drilling is done.

Inboard piece is hollowed and drilled to receive the rudder stock.



Drifts are set from the inboard side



Rudder-stock bolts set and tightened


Access port to accommodate wrench, nut, and washer

Graving piece (shaped carefully to close the void and to lock the nut}

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How To Have A Perfect Boating Experience

How To Have A Perfect Boating Experience

Lets start by identifying what exactly certain boats are. Sometimes the terminology can get lost on beginners, so well look at some of the most common boats and what theyre called. These boats are exactly what the name implies. They are meant to be used for fishing. Most fishing boats are powered by outboard motors, and many also have a trolling motor mounted on the bow. Bass boats can be made of aluminium or fibreglass.

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