Sound, dry and seaworthy, Ju-Be is a lot of boat for the money and time required to build it. Ju-Be is three pieces of marine plywood, two chines, a keel, a seat and two side planks fastened together with screws and marine glue. It can be rowed, poled or driven by an outboard motor if fitted with a suitable transom.
Side planks are two 3/4 x 12-in. fir or spruce boards, 16 ft. long. The bottom and decks are cut from marine plywood, the bottom 3/8 in. thick and the decks 5/8 in. thick. The three lower-right-hand details in Fig. 2 show the method of joining the curved ends of the side planks to oak nose pieces. Note that the width of the nose piece is given as 4 in. across the narrow outer face. This means that the width of the side planks at both ends should be about 4 1/2 in. to allow for planning flush. Cut the side planks to profile, Fig. 1, then screw the oak chines to the straight section of the side planks, leaving the ends of the chines free. Use marine glue in the joints. Now nail in temporary spreaders and bend the ends of the side planks inward as in the lower right-hand details, Fig. 2. Before screwing the free ends of the chines in place centre guide strips as in the lower detail, Fig. 2, to locate the centreline. Once this has been located, fasten the free ends of both chines. Then install the nosepieces, using marine glue in the joints. Next, fit the bottom ribs, spacing on 22 and 24-in. centres. Note that the midships rib is 2 1/2 in. wide to provide adequate bearing for joining the ends of the plywood panels that form the bottom.
Turn the assembly over and plane all joints flush, fairing the curves so that the plywood bottom panels beat equally on the full width of all members. Spread marine glue on the joining surfaces and unroll centre rib and across the lower edge of the nosepieces. Note the position of the tape with relation to the joint in Fig. 2, the circular detail. Install the bottom panels with 1 in. No.7 brass screws, countersinking the heads flush and spacing about 1 1/2 in. apart in a staggered line to prevent splitting the wood. Trim the overhanging portions of the plywood panels flush with the sides and ends. Install the oak keel.
Turn the assembly over and install beams to support the plywood decks. Cut the plywood deck pieces a trifle oversize, fasten in place with screws and glue and plane flush at the edges. Install the oak rubrail at the sheer, or gunwale. Fit an eyebolt at one end (or deck cleats at both ends) for tying up at the shore or pier. Fit seat rails, seat, oarlocks and the false bottom. The pole in Fig. 1 is optional. Finish the boat inside and out with marine paint.
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