METHODS OF BUILDING.

While but few of the many different methods of building are adapted to the purpose of the amateur, a description of the principal ones will enable him to understand the entire subject more clearly. Of these, two are by far the most common, the carvel, and the lapstreak, also called clinker or clincher. In the first, usually employed for ships' boats, yawls, Whitehall and other boats, where lightness is not of first importance, the planks (six to eight on each side) are laid edge to edge, not overlapping, and nailed to the ribs or timbers that make the frame, the latter being spaced from nine to fifteen inches apart. To prevent leakage, a small thread of raw cotton, lamp wick, or in large boats, oakum, is driven into the seams with a mallet and caulking chisel, and the seams afterward filled with putty, marine glue, or if oakum is used, with pitch. To stand the strain of caulking and to hold the cotton, the planks must be at least 3/8 in. thick, which would be too heavy for a canoe.

In a lapstreak boat the planks lap over each other a distance of one-half to one inch, the edges being held together by rivets; some of these also passing through the ribs. In all cases the upper board laps on the outside of the one below it. Three objections are made to this mode of building - liability to leakage, difficulty of cleaning inside, and the obstruction that the laps offer to the water.

As to the first, it is almost entirely dependent on the skill and care used in the construction, and although a lapstreak boat may sometimes leak when first put in the water after drying out for a long time, it will very soon be perfectly tight. While the second point is an objection, it is by no means a serious one, and with a little care the boat may be kept perfectly clean, if not, a stream of water from a hose will wash out all dirt. The third point is the one most emphasized by the opponents of the lapstreak, but they overlook the fact that the laps, or lands, as they are usually called in England, are very nearly parallel, not with the water lines, but with the course of the water, which is largely down and under the boat. At the ends the lands are diminished to nothing, if the boat is properly built, and that they detract nothing from the speed is well proved by the fact that a very large majority of all canoe races have been won by lapstreak boats.

As to their advantages, they are light, easily repaired when damaged and they will stand harder and rougher usage than any other boats of their weight without injury. The lands on the bottom protect it greatly when ashore, and if anything they add slightly to the initial stability.

The oyster skiffs of Staten Island Sound and Princess Bay, boats from 18 to 25 ft. long, lapstreak, of 5/8 in. plank, are considered by the fishermen to be stiffer and to rise more quickly than smooth-built boats of the same model. As after some experience with different modes of building, we have settled on the lapstreak as the best for canoes, and the easiest for amateurs, we shall later on describe it in detail.

In order to obtain a smooth skin, canoes are sometimes carvel built, as before described, but of 1/4 in. stuff, and as this cannot be caulked, a strip of wood about 1/4 in. thick and 1 in. wide, is placed on the inside of each seam between the timbers, the edges of the planks being nailed to it. This is called the "rib and batten" plan, and is largely used in Canada.

Another and similar plan, the ribbon, or more properly ribband carvel (not "rib and carvel") is used in Massachusetts and Connecticut for whaleboats, and in England for canoes. In these boats the ribbands are of oak or ash, 1-1/4x 1/4 in., slightly rounded on the back and as long as the boat. They are screwed to the moulds, when the latter are in position, just where the seams of the planks come, and as each plank is laid on, its edges are nailed to the ribbands for their entire length. When the ribs are put in they must be "jogged" or notched over the ribbands. In both of these methods the boat is improved if a strip of varnished or painted muslin is laid along the seam, under the ribband, but this is often difficult to do. In a similar way the boats of the yacht Triton are smooth built, with a strip of brass inside each seam instead of a ribband of wood. While having a very fine surface these boats are usually not as tight as the lapstreak, and are more easily damaged.

In another method sometimes employed for canoes, the skin is double, the boat being first planked with 1/8 in. boards and then with a second layer, crossing the inner one. The first layer sometimes is laid diagonally, sloping aft from bow to stern with the second layer sloping the other way, so as to cross it nearly at right angles; a method used in U. S. Navy launches and lifeboats.

Sometimes the inner skin runs across the boat, and the outer fore and aft, as in the well-known "Herald" canoes, and sometimes both run fore and aft, the seams of one skin coming in the centers of the planks of the other, rivets being placed along all the edges, a method of building followed also in some of our largest cutter yachts.

With either of these methods a thickness of muslin is laid in paint between the two skins, and both are well nailed together. While making a very strong boat, it is often heavy, and when water once penetrates between the skins, as it will in time (with the thin plank used in boat building), the leaks cannot be stopped, and the wood will soon rot. Another serious objection to it is the great difficulty of making repairs.

Boats and canoes are sometimes built of tin, copper or galvanized iron, soldered and riveted together, a method usually confined to ships' boats and lifeboats Two tin canoes were present at the first meet in 1880, and seemed strong, light and serviceable, though of poor shape. No doubt an excellent canoe could be built of sheet copper, that would not leak, and would be indestructible; but the cost and weight would be considerable.

In order to obtain a smooth skin with the advantage of the lapstreak, the planks are sometimes rabbeted on their adjoining edges, half the thickness being taken from each plank, leaving smooth surfaces, inside and out, but thicker plank must be used than in the lapstreak, and the working is more difficult. In another mode the planking is in narrow strips, perhaps 1x3/8 in. One of these is laid in place and nailed through from edge to edge, into the keel, then another is laid alongside of it and nailed to it, and so in succession until the boat is completed. A few frames are needed to stiffen the boat near the masts. In the boats made by the Ontario Boat Company these strips are tongued and grooved, then steamed and forced together, the strips in some boats running fore and aft, and in others running around the boat, from gunwale to gunwale. In shell boats, where a very fine surface is of much greater importance than in canoes, the skin is made of Spanish cedar, about 1/8 in. thick, laid in four or six pieces, joining on the keel, and once or twice in the length of the boat, making one longitudinal seam and one or two transverse ones; but this method is not strong enough for canoes.

Paper has been used for the past thirteen years as a material for canoes, but although the boats are strong, tight, and but little heavier than the lapstreak, they have not become popular, and are but little used. The process of construction is patented, and requires both tools and experience beyond the reach of the amateur. Canoes have been built during the last five years on a similar system, using thin veneer in three thicknesses instead of paper, but, besides their great weight, no glue or cement can be depended on when long immersed in water; they are open to the same objections as all double-skinned boats, it is only a matter of time before leakage begins, after which they are practically ruined.

One of the oldest modes of boat building was to make a frame of wickerwork or similar material, covering it with leather, a method still followed, except that canvas is substituted for the leather. This mode of building is perhaps the easiest of all for the amateur, and we shall devote a chapter specially to it further on.


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