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water line across the ribs.

Note that often only half of the ribs are drawn, so you'll have to draw the mirror image of each rib the best you can including the added ribs.  When I do so I use a light tracing paper that you can see through easily, draw half the rib, fold the paper in half then copy the other half of the rib off the first half.  Another method is to make a copy of the ribs then trace them on the back of the paper copy, thus making a mirror image.  When you have a complete set of full width ribs COPY all of your work and save the original drawings.  Make one copy for each of the ribs.

For each rib highlight the correct exterior hull line the top and bottom (remember to follow the lines that allow for the bottom plate and the caprail).  Also on the exterior line mark an 1/8" deep notch on each side of the rib at a point starting one inch below the waterline and extending to the bottom of the rib.  Hardwood stringers will be installed here later on to help form the impenetrable area of you hull.  On some of the wider ribs you will not need a rib that goes completely across the bottom of the hull.  If the flat spot in the rib is more than 4.5" wide then you will draw a left and right piece.  You may wish to read the section on water channels at this point so you can design your rib patterns to accommodate water channeling.  The water channel will be 2.75" wide so measure 1 and 5/8" inches left and right of the center point on the flat bottom of the rib profile to allow for the water channel stringer.  Make these marks ¼" high.  At the outer edge of the spot measure ½" up and draw a diagonal from that point to the top of the ¼" tall line that marked the top of the innermost edge of the rib's bottom.

Next sketch in a line about ½" in from the exterior hull line to complete the inside edge of your rib. You will want to mark the location of the prop shafts on the appropriate rib patterns, usually the rib just forward of the propeller and the two ribs forward of where the shaft enters the hull.  For the rib just forward of the prop you will need to draw in braces to support a circle big enough to drill the hole through for the prop packing tube.

The next items to make patterns for are the bow and stern keel plates, the caprail, and the baseplate.  Start with the base plate.  Take your rib patterns and measure the "flat" width at the bottom of the ribs.  For all ribs with a flat spot at least 3/8" wide and that touch the bottom plate transfer those measurements over to a sheet of paper.  Remember to also measure the distance from the bow to each rib from your overhead view and transfer these to your base plate pattern.  You should end up with a center line with rib locations marked and each rib location will have a perpendicular line centered on the center line that represents the width of the flat bottom of the rib.  To complete the base plate pattern just connect the outer edge of the rib lines.  Next to make the bow and stern keels trace the side view of the bow and stern profile.  Measure in about ½" in from the profile and make another line.  You will want to make the keels long enough to overlap the base plate at least 3 inches.  Remember to make a 1/8" allowance for the base plate.  Also note that a few of the forward and stern ribs will not attach to the base plate but to either the bow or stern keel.  These rib drawings should be modified with a notch to slide onto the keel and remember to keep the depth of the ribs all the way to the bottom of the keel, since they do not rest on the bottom plate.  Some ribs that are on the base plate may need to have a notch added to their pattern to allow for the overlapping bow and stern keels.

To make a pattern for the caprail trace the outer edge of the ships deck from the overhead view (please note that some odd ships are wider at the waterline then at the deck or caprail level).  Draw a second line a ½" in to complete the pattern.  You

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