I took 1/2" square dowels and trimmed them in one of the dimensions to a little less than 3/8", leaving them 1/2" wide in the other dimension, as the blueprints suggest. First I had to trim the dowels (carefully and safely) using the table saw:
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Next I cut the steep angle that rests up against the bottom of the skirt:
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Then I cut the other angle that runs parallel with the top of the skirt. This will be cut flush with the top of the skirt later using the router to shave off the part that rides above the top of the skirt:
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Finally I primered them, along with the legs that I had been sanding and primering throughout the weekend:
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I just need to glue the ribs on and route them down to size. May need to sand the inboard parts of the ribs to make them fit the skirt snugly in places too.