Compil ed by the Editors of Popular Mechanics Magazine

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Copy right 1950 by Populo r Mechonics Co.

Bootbuilding is part of the American heritage. The settlers of New England developed the sturdy dory to cope with the storm-wracked Atlantic waters in which they fished. It was a rare son of Maine or Massachusetts who could not fashion his own boat with crude hand 1001s. The rivers ot America were explored by men who learned from the Indians how to make bark and dugout canoes. Flatboats carried a large part of the goods of the pioneers during the westward movement. Today, boatbuilding is no longer a part of everyday life, except in some fishing communities where boats slill are built by men who earn their livelihood from them. But there ore a surprising number of amateur boatbuilders.

Altogether there are more than half a million persons in the United States who are regularly building boats for pleasure or for profit. They form a cross section of American life. The sleek mahogany cabin cruiser of the Chicago banker shares Belmont Harbor with the plywood sailing dinghy of the shipping clerk. On Chesapeake Bay, in the Florida Keys, and through San Francisco's Golden Gate, the rich man's selfdesigned yacht and the home-built sloop of the ordinary man head out toward the open sea together. Self-built canoes and rowboats of fishermen and hunters glide on the inland rivers of the country, and on its lakes, ponds and marshes. Theirs is a double reward-the pride of craftsmanship and the thrill of navigating Ihe boat when the building is done.

With all this in mind, the ed itors of Popular Mechanics have chosen wilh care the croft that make up the contents of 23 Boals You Can Build. Boats built from these plans are now in successful operation in various parts of the country. The instructions, pictures and plans were prepared for ease of understanding. Those who have never built a boat before are urged to read ParI 9, "Build Your Baal Right," which begins on page 161. The editors believe this book offers something to tem pt every lover of boats- a pion that will make his hands itch for tools and materials. Choose your favorite- cobin cruiser, sailboat, rowboat, inboard, outboard, ice yacht, bicycle baal, canoe, kayak, sea sled, paddle board, catamaran. Good building, happy launching, and bon voyage!

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The kind of a boat you'd like to have is sure to be within the covers of this book. In 23 BOATS 'lOU CAN BUILD, the editon of popular r-.lechanics present a wide variety of craftranging from "Seacraft," a 25-foot cabin cruis'er sleeping four persons, to "Tiny," a six-footer that flaunts a muslin sail from a boom made of a sawed-off broomstick. There's "Su-Lu," a plywood dinghy built like a Navy PT-boat ... three boats of sheel plywood . . . an eight-foot duckboat for sportsmen . a three-section rowboat thai fi.ts inside itsell like a Chinese box puzzle ... a CanadianIype canoe ... a kayak of the North . . . a ponloon boat pedal-powered by a converted bicycle a sea sled that runs on a converted washing-machine engine. . a racing ice boat that will take you skimming along at more than 80 miles an hour ... a mol or_driven catamaran ... a paddle-propelled pontoon.

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PART 1 "Su-lu"-the PT-Type Plywood Dinghy PART 2 Trio in Plywood PART 3 "Seocraft"-o 25-Foot Cabin Cruiser PART -4 Bools for Sportsmen PART 5 "Zephyr"- l-4-Fool Soiling Dinghy PART 6 "Arrowhead"-21-Fool Sloop PART 7 "Just for Fun" Croft PART 8 Training "Ships" for Young Sailors PART 9 Build Your Boat Right PART 10119 99

7

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Seamanship and Servicing Your Boot

177

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PART 1

"'See-Lee" - the PT-type Plywood Dinghy

Robe.t t. Smith, Monrovia, Calif., builder of the o,ig;. nol "Su-tu," hold. the light but sturdy boat upright with one finger. Ther. or. no

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Wilh Iwa pa ueng ers aboard, "'Su_lu" planes the walft. like Navy PT bagl" afler which it wgS pallerned

"Set-Let"-- a Plywood DinghyTHIS LIGHT and sturdy little dinghy is actually a 1O-ft. model of a Navy PT hull, that is, with adaptations to the materials used and to the limitatio ns of a home workshop. "Su-Lu" can accommodate four adults and is light enough for one person to pulon top of a car. The "skin" is merely two layers of %-in . plywood with muslin between, laid (lVel" a frame of spruce battens. The result is a rigid, strong but very light shell. The transom is built to take an outboard motor, and a mast step and centerboard tJ'unk are provided for sailing purp oses. Oarlocks and sockets also may he ploovided, though not shown on this model. Erecting frame: Once the strongback and station molds are properly installed on the erecting frame, the shape of the hull is bound to be correct. As in all small boats, it is most convenient to build upside down and the erecting frame is thus designed. First make the strongback, Fig. 1, of a::! x 7 plank, notched to receive the five station molds and cut away to clear stem and transom knee. If your workshop has a wooden floor you can set up tJ1e erecting frame directly upon it. If a concrete or dirt floor is used, however, you shou ld make a large open rectangle of planks with corner braces and cross members upon which uprights are SUppol"ted, as in Fig. 4, which in turn carry the strongoack. Note that the strongback is also supported at the end by 2 x 4s, but that these al'e not screwed to it, in order that when the boal is lifted up to be turned over, the strongback will come away. This applies also to the upright supports amidships. A taut wire is installed as shown by which the station molds are to be centered. In Fig. 2 is a side view of the eloecting hoame with stem, transom and keel in place. These are tempol'arily secured willi screws for removal when the boat is turned over, and so that the stem can be taken off for cutting the batlen notches after marking them while on the frame. Diagonal braces are located where indicated, and these are screwed to the frame only at the bottom

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where they will be accessi ble for a screwdriver. These are illustrated in the sectional view, F ig. 6, Their pUl'pose is to keep the skl.tion molds centered d uring con struction, After the hu ll is completed and lifted oIT, it is set on the frame base w ith wedge blocks, as in Fig. 5. SI:.tion molds: As long as the profiles are correct, the station molds may be of a lmost any ty pe, and F ig. 3 is only a suggestion, Note that the cross brace is assembled with wing n uts for easy removal. Ol'dinal'Y screws may be used instead of wing nuts. In p lacing the m olds on the strongback, notches should be cut deep enough to permit the bottom of the mold to lie flush with the edge of the strongback . Also, the edges should be beveled to conform to the curve of the huD. In Fig. 8 are shown the deck plan and outboard pro61e of the finished hull, without the false bottom 01' sailing equipment. Note the oversize knees at corners of transom, w hich can serve as seats in handling the tiller under sail 01' on other occasions. Profiles of the five station molds are given in F ig. 9. Approximate locations of the battens are indicated on Station 1 only. Sheer an d chine battens are indicated on the others. After the molds are completed, make the keel of white oak, % in. x 3 in, x 9 ft. Part of this will be cut off the aft end latel'. At a p oint 30 in. from the forward end, it begins to taper from 3 in. wide to Ilh in. at the forward end . A slot for the cen terboard, ~8 in. x 10lh in., is cut through where indicated in the upper detail of Fig. 7. The keelson is seeured temporarily to the strongback with screws as indicated in Fig. 2 and also to stem and Uansom. The stem: The stem may b e made of white oak, apitong, Or, as in this case, ma-

hogany. T wo %-in. pieces are glued together to form Ilh-in. thickness. It is made in two parts, F ig, 10, the joint being bolted and glued and provided with stopwater plugs of soft pine. Installed dry, these plugs swell to a very tigh t fi t and prevent leaking at a critical point. The two parts al'e bolted with galvanized carriage bolts, the heads countersunk, In the final assembly, bolts are used to fasten to keelson. Cut the stem longer at the top than shown to allow for trimming flush with the top of the sheer battens. Bevel the for ward edge somewhat to simplify getting marks for batten notches, and later plan e the edge flush with the battens to receive the plywood skin in a watertight joint. In all assembly operations on this boat, use a waterproof cement recommended for this purpose. The transom: An exceptionally strong transom is made by building up two layers of 3f.t-in. mahogany with the grain at right angles and the profile as shown in Fig, 11. The grain is vertical on the forward side and horizontal on the after side. This construction also simplifies making the n otches for the b attens, which can be sawed instead of chiseled out. The transom knee is also shown in F ig. 11, and is installed with galvanized flaU.ead wood screws, heads countersunk and plugged over with marine dowels, Use this type of dowel exclusively on the boat because the grain I'uns across and they can be trimmed flush with the boat neatly w ith a chisel. Nole that notches for battens are only half way through the transom, whi le the notch for the keelson goes all the way through . Installing batte ns : The shcel' line should be marked on stem as well as station molds before bcginning to install battens. With keelson, stem and transom on the erecting

left: Clolh betw ee n inne ' and OllIe. lay e .. of plywood ha l nOI yel bee n l,i mmed all,,,n ~"m . NOle bevel "n keel_ , ,,n, e nd of whieh i. 10 be . owed off flush. Rig hI: Sleom-b ent oak '~1'~

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runner clamping pieces come next. These are fastened to each frame and holes are drilled in them for the runner bolts. The holes are located either aft Ot" forward of each bottom timber as indicated in Fig. 10. Do not pass bolts through bottom timbers. The mast step block is fastened to the bottom timbers as shown in Figs. 9 and 11. The mast step itself is a length of %-in. galvanized pipe. This is threaded into a standard pipe flange and the flange is screwed SeCUl"ely to the must step block. The pipe should be just long enough to pass through the mast partner, which pt'oyides an upper step, and the deck strake, coming flush with a flange screwed to the strake. Cockpit frami ng and the stanchions which support it are installed next. Note that stanchions also are installed at the center of the frames, fore and aft of the cockpit. The ends of the stanchions at'e cut to lap the face of the frames as shown in the detail above Fig. 12. With all interiol' fmming completed up to this point, the decking is laid. Narrow planks, 1 % in. wide, make this a simple job. The same procedure is followed here as was used in planking the bottom, working outward from the deck stl'ake and trimming off the planks flush with the inner chines. For a neat job, countel'sink all screws and fill with wood putty, As will be noted in Figs. 8 and 11, the face of the inside chines and the edges of the deck and bottom planking are covered with an outside chine piece, 1h: in. thick, which also is beveled off flush with

the deck and bottom planking. Before fastening the outside chine, the rub rail should be flanged ovet and tacked to the inside face of the chine. The rub rail, of brass or copper, is applied to the chine from the mast station to the aft end of the cockpit and prevents scuffing when the hull is heeled over. After the outside chine has been fitted, the sheer t!"im is attached. This is set inward about 1f4 in. and covers the joint between the decking and the outside chine. Completion of the hull involves fitting a CO' V """tom "0". Su'" .b'. '0. moto .. b' ,~ H hp, R ........ . ''''''. _"". 5",. " " 'n.hr.--S3, ."'

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