| |
|||
|
|
|
|
|
|
A note from Dan, your
genial
host: This article was published in Industrial Arts Those familiar with W.P.
Stephens' book Canoe and Boatbuilding for
Amateurs |
The reason perhaps amateurs do not try boat building more than they do is because there are technical difficulties which seem to throw a barrier in the way.
In the July number of The Industrial-Arts Magazine, 1915, I told how a motor boat was built if the manual training department of a Seattle high school. The purpose of this article is to tell how a two-passenger sailing canoe was built by Vernon Gardner, a junior in the same high school. The canoe was designed, the parts were cut to shape, then assembled and finished entirely by the pupil. It cost him two hundred hours of his time and thirty dollars, which is one-third of the price of such a canoe.
The boat is fifteen feet long, thirty-eight inches wide, fourteen inches deep and clinker built with a pit two feet by two and one-half. The keel and posts are of oak, the planking and deck are of Washington cedar, the combing and minor trimmings are of mahogany, the boat is finished thruout a natural color except the bottom, which is painted.
The first thing which was taken into consideration in the building of this canoe was the design. Here our chief concern was that the boat when finished would be a seaworthy craft. After examining magazines and books, visiting boat manufacturing plants and consulting with boat builders the design as shown in the drawing was decided upon.
With this data at hand a drawing was made to scale. Next came the laying down, that is, the enlarging of parts of the drawing to full size, and this drawing was used as a pattern for the various parts that are needed in the construction of the framework. The second drawing being completed the molds were made, seven in number. These were made of scrap pieces of lumber which were bolted together and then sawed to the correct shape, Fig. II. Next a flat oak keel was made as shown in the drawing, four inches by seven-eighths inches. The keel is four inches wide in order to give strength and also allow sufficient width for the centerboard to go thru it. The slot in the keel is one-half inch wide and five feet long to admit the centerboard and the head ledgers. The keel batten, which is the strip nailed on top of the keel, projects beyond the latter one-half inch (see Fig. VII), thus forming a rabbet on each side. The stem (for construction refer to Fig. IV and IX) was sawed out and planed up three inches thick and rabbeted so that the ends of the planks would come flush on the sides of the posts. Next the centerboard trunk was put in (get location from Fig. IV and VII). The head ledgers, which form the ends of the trunk, are of oak one and one-half inches wide and one-half inch thick. Then a groove one-fourth inch wide and one-fourth inch deep was cut on each side the entire length of the opening for the sides of the trunk to fit into. The head ledgers were fitted into place now. A one-fourth inch shoulder on the ledgers rests on the keel. The remainder of the ledger goes on thru the keel. The sides of the trunk, which are composed of one-half inch cedar boards, have a tongue fitting into the one-fourth inch groove and are fastened with copper rivets. All the joints in the construction so far were given a coat of white lead before they were fastened together.
The molds were now placed at equal distances after a small piece had been cut out of each to fit over the keelson flush with the boarding line. They were then tacked to the keelson and further held by ribbands one-half inch by one inch, one nailed to each side the full length of the frame work. Next the keel was turned uppermost and stem, stern post and molds were plumbed and shored firmly. Stop-waters were now put in to keep out any water that might otherwise cause a leak by following a seam. Stop-waters are small plugs of dry soft wood. The holes were bored where the joints cross the rabbets as shown in Fig. IV.
The rabbet which was partly made in the stem, stern post and keel before assembling same, was now completed with a chisel. A strip one inch by one-fourth inch by five feet or more in length was used as a guide. This guide was held across the molds lengthwise of the boat. One end of it was applied to the rabbet, then the wood was cut away until the surface of the strip and the outside of the stem and stern coincided. In this way a good fit for the garboards was obtained.
The positions for the ribs were next laid off, six inches apart. This marking was done at the top and bottom of the frame and in such a way that the markings could be seen from the inside or outside when the planks were on to avoid putting rivets thru the planking at the location for the ribs. The riveting at those places was completed when the ribs were put in. The planking came next. In order to avoid distorting the shape of the boat the planking had to go on in such a way that only a limited amount of strain from one piece would come upon any other. The planks are Washington cedar one-fourth inch thick, four inches wide and they all run the full length of the boat. A fit cannot be obtained by springing the planking edgewise. Strakes are sometimes "sprung on" by experienced builders but amateurs should not attempt it, for the chances are that the framework would be pulled out of shape. The garboard, that is, the plank nearest the keel, was laid first. It was clamped down to the center mold with a hand screw and the ends were bent down so that the plank touched all the molds without being bent edgewise.
In this position the garboard was measured up in order that it could be cut to fit properly in the rabbet of the keel, stem and
stern post. The garboards were fastened by boring small holes into the keel, three in each space left for the ribs, and copper rivets were inserted two inches apart to hold each garboard in place. Brass screws were used in stem and stern, the planks were always drawn up to a snug fit with clamps, and not with the screws or rivets, to avoid splitting the boards. All the planking was steamed before fastening same in place. A description of a steaming box and how to make it is given in The Industrial-Arts Magazine for July of last year. All the calking that was used in the boat was in the rabbets of the keel, stem and stern posts. The calking was soaked in thick white lead before it was applied.
Next it was calculated how many planks it would take to cover one side of the canoe. None of the boards when fitted have parallel sides, so in order to have every board reach the full length of the canoe it was necessary to determine beforehand the width of each one at its ends. To have the lapping properly done between ends and fit edgewise at stem and stern each board was fitted and cut separately. In this canoe the planks lap five-eighths of an inch between ends, and in nearing the ends the boards are beveled; at the stem and stern the fit is flush and there is no lap.
In planking, the boards were placed alternately on each side and thereby both sides were planked at the same time, so to speak. When the planking was finished the canoe was turned right side up and the keel blocked to the proper rocker. Fig. IV.
The holes for the rivets to hold the ribs were now located with a batten which was bent at the proper location for the ribs and used as a guide to get the correct alignment. Next the ribs were cut to dimensions one-fourth inch by. Three-eighths inch from straight grained white oak. After they had been steamed they were put into place while. hot and later riveted fast. The riveting was begun at the keel and continued to the top of the boat. As many ribs as possible were put in before any molds were removed. It is customary to leave the molds near the bulkheads in, but instead they were removed and extra two-piece ribs were inserted, the bend being too short to allow for a single piece.
After all the ribs were in and the gunwales fastened on, the molds were removed. The boat was kept from spreading by means of cross-spalls which were fastened to the gunwales. The gunwales, which were made of fir one inch by three-fourths inch, support the cross beams of the deck and serve as a chafing batten protecting the sides of the boat. They were fastened with a rivet in each rib, stem and stern post.
Next the steps for the mast plates were fastened to the keel fore and aft. Then the deck beams were cut with a crown of three inches, giving ample stowage space below the deck and making the curve sufficient for the boat to free itself quickly from a wave. The beams are fastened to the gunwales. They are one inch deep and one-half inch wide, except the beams that support the masts, which are four inches wide in order to take a two-inch hole for the mast tube.
Before putting on the deck the floor was laid. It is customary to place the floor boards directly on the timbers, in that way giving more room below deck but allowing the water to cover the floor if there should be a leakage or if a wave is shipped. In this plan the floor is raised two inches, in that way keeping stores dry even tho there is water on board. The floor is carried on beams one and one-half inches deep by one-half inch wide fitted closely to the planking. Limber holes are cut in each piece to permit a free passage of water. These boards also help to strengthen the canoe.
After the floor was laid the deck was put on. An opening for a cockpit two feet by two and one-half feet was left, which gives ample room for two passengers. The deck is of Washington cedar, laid in two pieces one-fourth inch thick with a seam down the center which is neatly covered with a one-fourth inch by five inch mahogany strip. The side decks are supported by six braces or knees on each side sawed from spruce one-half inch thick and screwed to the planking and gunwale. A hatch was cut thru the deck and a cover was made to fit it. Fig. III.
Next the combing was put in place, which is mahogany one-fourth inch thick, three inches high forward and
one and one-half inches aft. The front comes to a point and the after end is square. It is riveted to the side braces and the deck.
Now a few words in explanation of the centerboard. The first essential of a sailing boat is its lateral resistance, by reason that it can be sailed to windward. For a canoe a keel or a centerboard is necessary. A centerboard was used in this canoe in preference to a high keel for the following reasons: First, the boat with a centerboard can be turned more easily; second, it will stand upright in shallow water; third, it permits easier landing; and fourth, there is less danger of running aground because the centerboard can be raised in shallow water. The question of the weight of the centerboard is important. Sailing canoes require some ballast and with a centerboard the weight can be carried lower than in a canoe with a keel. This particular board has a drop of sixteen inches. Fig. IV. It is made of galvanized sheet iron three thirty-seconds inch thick, contains two square feet in surface area, weighs thirteen pounds and is of such a type that it can be moved forward or aft with a little car to carry it. Fig. III. The car was made of a mahogany board twenty-four inches by three and one-half inches by one-half inch; it has four wheels one and one-fourth inches in diameter and two pulleys, one to let a rope down vertically thru the board and the other to carry a rope horizontally to the fastening at the cock pit. Fig. III. The rope carries most of the weight of the centerboard.
The rudder is made of mahogany three-eighths inch thick, eight inches wide and eighteen inches long. The rudder steering arm is cast brass. Ropes from the steering arms transmit the motion from the
tiller, which is just aft of the cockpit and in front of the mizzen mast, to the rudder.
It is necessary to have a seat of some kind in a canoe, but it should be as low as possible in order to keep the weight low.
Before the mast plates, cleats and screw eyes were put in place the boat was given two coats of boiled linseed oil; after the oiling the bottom was painted and the rest finished a natural color, but received three coats of exterior varnish.
The question naturally arises how large a sail or rigging a canoe should carry. This is determined by making a comparison of other boats. The chief elements, however, are the personal qualities of the canoeist, his prudence or good judgment, daring, agility, and skill in handling a
canoe. One man may use one hundred square feet while another would not be safe with half that amount. On the canoe built in my classroom, main and mizzen have a combined area of sixty-five square feet, fifteen in the mizzen and fifty in the main mast, which also has a patent reef. In a canoe the sails should be spread well fore and aft, long and low, rather than narrow and high, for the propelling power will be as great and the keeling power much less. In order to obtain a proper balance of the sails the center of effort should be nearly in the same vertical line with the center of the lateral resistance of the keel. With regard to the general shape of the sails I refer you to [the Figure].
At the close of school the canoe was completed. After launching same all anticipations were realized; the canoe sailed perfectly at a good rate of speed and has proven itself a seaworthy craft. During his vacation the pupil had the pleasure of spending his leisure in the sailing canoe be himself had made. An ambition realized, two credits earned, and a happy summer over, he sold his canoe for twice what it had cost him. But he is not minding the loss of the canoe too much, for already he is planning to build a twenty-four foot launch next semester.
Back to the Canoe Sailing Page.