Chapter 7

Hulls And Their Characteristics #2

There are two basic types of keels. The fin keel is the least popular and its use is limited to racing boats (Fig. 11). Considered in an elementary way, it looks like a dagger centerboard that has been lowered all the way and fixed in place. Usually it is an iron casting with a cigar-shaped bottom acting as ballast. Note that it cannot be raised or lowered. Whatever its distance below water, that is the minimum depth of water in which you can sail. Most fin keels, even on small boats, require at least 36 inches of water.

Note one important point. Either type of centerboard adds to the area of lateral plane but has little or no stabilizing action. Fin keels combine the advantages of the added area plus providing ballast. The result is that most keel boats have narrower beams than center boarders. The latter provide the required ability to avoid capsize by means of added boat width. The former gain much of their stability from the low position of the ballast. From a comfort standpoint, most center boarders have more room than their narrower cousins with keels. Either type when properly designed is safe from capsize when intelligently sailed. It is true that the narrow center-boarder is more apt to capsize than a keel boat of the same width, but a center boarder designed for stability rather than for the maximum possible speed will not capsize unless sailed by the wind jamming equivalent of a hot-rod driver. A fool can capsize any boat ever designed while a prudent individual can sail for a lifetime without getting into a capsize.

The other type of keel, and the one found on most of the larger sailing craft, is the full keel (Fig. 12). Instead of being of dagger shape, the full keel is generally triangular when viewed from the side. The apex of the triangle is at the bow and the base is aft. Iron or lead ballast in the form of a casting is attached somewhere along the bottom of the keel. Such a keel is very strong, has a great deal of lateral plane area, and stabilizes the boat due to the low position of the ballast.

Of all types, the flat bottom is most popular. Although perhaps not as beautiful as other types, it is easy to build, particularly if the bottom is planked athwartships rather than fore-and-aft.

A variation that is sometimes found is the combination keel. This is much like the full keel except that it is not quite as deep. To add enough lateral plane area, a center-board is also used. In a few cases, the keel itself is deep enough so that there is no centerboard trunk inside the boat above the floor line, the entire depth of the board being within the keel depth.

In an arc bottom, the bottom lines, instead of making a V. more closely resemble the letter U.

Hull construction does not differ as much as hull shape. Ninety-nine boats out of 100 are built of wood. This has been going on for something like 20 centuries and, if this writer can be believed, will go on for quite a few centuries more. Wood construction is of two basic types. Conventional boats are built over frames—called ribs by no nautical folks—and are covered with wooden planking applied in strips, the seams of which are backed with battens or talked to prevent leakage. No matter what anyone tells you, this system of boatbuild-ing can never be discounted. It is the favorite method used by the vast majority of designers and builders.

The second type of wooden boat is planked with plywood. This must be waterproof. The ordinary plywood you buy in most lumber yards is worthless. As the plywood is applied in large sheets, it might seem at first that the method avoids seams and is easier to build. We cannot get into a subject such as spherical geometry in this discussion, but the fact remains that a plywood sheet cannot possibly be bent over the normal boat form. To use sheet plywood, therefore, the designer must develop his hull form so the sheets will fit the hull surface. The net result is that the hull form cannot be of the exact shape that might be required by the laws of water flow. The hull must be designed to suit its planking rather than the planking being formed to suit the hull shape having the least resistance.

To overcome this objection, there is the molded-plywood hull. This system only applies to round-bottom boats. Such boats are built up over extremely expensive molds. A layer of thin veneer is applied to the form and then coated with a waterproof adhesive. On top of that another layer of veneer is applied. Several thicknesses are built up so that, in the end, there are no seams that pass through the several thicknesses. The objections are that the method is still not applicable to all hull shapes and that the initial investment is so high that most such hulls are built by the plywood manufacturers themselves and sold, in semi complete form, to various boat builders who finish the hulls up and put on their own nameplates. There are scores of boats on the market that have identical hulls although each is sold under a different trade name and touted by the sales department as the last word in hull development. The high cost of the molds and the other apparatus needed for this molding process makes the idea impractical for any but the very small hulls. Some larger boats have been built experimentally, but at ridiculous cost. For the amateur boat-builder, the method is out of the question. One authority has stated that the investment is unsound if less than 300 hulls are to be built from the same molds.

Most large sailing craft have big, strong, full-length keels such as is shown on this model boat.

The Raven's centerboard is hung on rollers so il can be moved forward and aft to get desired balance.

Some metal hulls have been built. This is nothing new. In fact, it is probable that there were more small metal boats built 40 years ago than there are now. As this material has so seldom been used for sailing craft, it can be dismissed when discussing the boats with which we are concerned.

Some mention must be made of the use of plastics. Much has been written about this material in recent years. Again, a permanent mold must be prepared so the method is hardly suitable unless boats are to be mass produced. At this writing, the costs are high and the boats have not been in service long enough for us to be sure that the various forms of plastics used will stand up as long as would be the case with a conventionally planked boat. Perhaps plastic will live up to expectations and become the universal method for the building of boats produced in quantities. Right now, the idea must be considered as still in the experimental stage. Builders have come rushing into the field with plastic hulls and have withered miserably on the vine. Some others have been using the idea for several years. We can do little more than adopt a wait-and-see policy.

In a Lightning, the centerboard is held in its "up" position by a pin in a hole in the board.

Hinged centerboard in a Bantam. When sailing before the wind, the centerboard is raised up.
 
Dagger centerboard in a Snipe. This type isn't hinged; instead, it is bodily raised or lowered.
 
Now comes the big question. What type of boat is best? There is no simple answer. It all depends upon conditions. The attitude of the prospective owner has a great deal to do with it. Many a youngster has bought a sailboat because it is reputed to be fast. This is just as sensible as going on a spinach diet because you are fond of dark green. Before you buy a sailboat on the basis of its speed, make sure that you are going to race in regulation regattas. If that is your idea, be prepared for several seasons of learning the tricks of racing as well as being sure that you can afford to keep your boat in racing condition. If, like most people, you want a sailboat for fun—for what is known as "afternoon sailing"—you certainly do not want some old barge that cannot get out of its own way, but you might be better off with even that than you would be with a racing sailor. Racing sailboats, like racing cars and thoroughbred horses, are intended for speed without much thought being given to comfort or a long-lasting investment.

Many of the one-design classes are popularly supposed to be combinations of racing boats and general sailors. A few live up to that reputation pretty well, but they do not go out and win regattas unless you keep them tuned up on dollar bills and elbow grease. Almost all of the racing boats belong to some of the one-design classes. Each must be registered in its class in order to compete. You may find that the book of rules for the class is as complicated as the instructions on your income-tax blank. In any case, the best way to determine if some of the class boats are what you want is to hang around the waterfront, talk to owners, and—in particular—see whether they use their boats for general knocking around. If you find the boats are being used only on race afternoons, you can bet your final buck that you want something else unless you, too, are willing to pamper the little pets six days a week in order to sail for a few hours on the seventh day.

If racing is to be of secondary importance, your field of choice instantly becomes wider. Not only do new types come into the picture, but you still have some of the semi racers to consider—boats with a fair amount of strength and space that will still provide a lot of fun even if you do not keep them tuned up to save a second per mile. Few small racing boats have even an excuse for a cabin. Yet you can get a sailing boat no longer than 18 feet that will provide you with enough cabin so that a pair of you can go off for week ends with some sort of comfort. You will have to cook on a camp stove held between your knees, and you certainly will not find a tiled bathroom with hot and cold water, but you will be able to work in a couple of comfortable berths and find a place to stow your toilet bucket, your shore clothes, and some camp-cookery gadgets. You'll have a cruiser and will be entitled to slap your chest and talk about the South Seas and Red Sea pirates. Wait a minute, bud! Have you any place to cruise? If your sailing is to be done on some little lake you can cover from end to end in a few hours, a cruiser sounds a bit silly unless you are very, very young and will get a kick out of trying to sleep in a barrel-sized cabin when, a mile or two away, a soft, white bed in a pink-and-white room awaits your pleasure.

A small cabin, too small for you but big enough for the lunch, the picture snapper, and some fishing gear, is called a cuddy and is a swell thing on any size of boat. A rain squall may turn you into a soggy mess, but you will be happy to know that the camera and the sandwiches are dry. Better yet, the cuddy may be large enough for you to cram Aunt Emmeline into it should rain come from nowhere the day you take her out for her first experience afloat. Even if it doesn't rain, the wind may come up and send sheets of spray flying over the ship. You may have read of the thrills of having the taste of spray on your lips, but Auntie Dear will consider it as simply damned wet water running down her spine. Thus a bit of cabin is to be desired even on Lake Five-by-Five.

How rough is rough? The guy who staggers into port the day he meets his first choppy trip, screaming that the seas are running 12 feet high and that nothing but his splendid seamanship kept the hooker afloat, will usually be met by the professional seaman who will grudgingly admit that the weather is one stage from being a flat calm. Rough water to some means any little ripple that turns white in the wind. To others, rough water is rated by whether-the seas are running as high as the masthead.

There are plenty of places where rough going will never be faced, where almost any tight boat can be sailed irrespective of the weather. There are other spots where heavy weather is the rule rather than the exception, where many small boats can be sailed but a fraction of the time. Never, never buy a boat for use in a section that is strange to you. Without fail, be sure that you frequently visit the place where you will sail. Study the sort of boats used by the natives, not the pretty little boatlets brought in by the summer boarders. Is the section noted for its sudden summer storms? If so, you want a boat that can be quickly reefed and can be horsed along toward home in anything short of a hurricane.

How deep is the water? As previously discussed, this determines whether you can use a keel boat or must have a center-boarder. When you are not sure, select the latter. You can sail a centerboarder in water 10 miles deep, but your keel boat is a menace just as soon as the bottom comes within a few inches of the keel.
 
Dagger rudder on a Snipe. This V-bottom craft is the most popular one-design sailboat in the world. The hard chines make the boat stable.

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