In essence the chine curve is extruded upward following the transverse contour defined by these identical futtock timbers. While working with archaeologist Peter Fix on a conservation assessment of the flat-bottomed gunboat Philadelphia (1776), housed in the Smithsonian National Museum of American History, we discovered several shipwrights' "V" marks as well as offset lines, very similar to those depicted in Figure 49e, scribed on a section of exposed bottom planking along the chine (Figure 50) (Pevny 2010). These "V" marks are very similar to surmarks in terms of the underlying design concept, and yet they are located on the longitudinal hull planks and not on transversely oriented frames. This example underscores the importance of differentiating between design concepts and their manifestation in the construction sequence.
Framing Patterns and Templates
Templates are made from thin planks, while actual framing timbers have substantial sided dimensions. Therefore an unbeveled framing timber will only fit the curvature defined by a template along one of its vertical faces. Which face conforms to the hull curvature depends on whether the timber is positioned before or abaft the conceptual design plane at the frame station (Figure 49g).
As is shown in Figure 49g, from amidships forward, an underbevel has to be cut for any timber before the design plane and a standing bevel for any timber abaft the design plane. When laying out for underbevels, there is always the assurance of excess wood that can be cut away to make the outboard face conform to the hull curvature. In Figures 49h, 49i, and 49k all the floor timbers are positioned for underbeveling relative to the frame station. Figures 49h and 49i depict variations of a stepped framing arrangement, and Figure 49k shows the same partial double framing arrangement as on La Belle.
In Figure 49h the first futtock at frame station VIA is placed on the side of the floor timber oriented toward amidships, its after face. Thus the adjoining faces of the floor timber and first futtock align with the frame station line at the theoretical design plane defined by the templates. There is no documented example of such a relative placement of first futtocks to floor timbers that has been associated with traditional Mediterranean moulding. There is some evidence that such a relative placement of floor timbers and first futtocks was used in English shipbuilding. An early seventeenth century shipbuilding manuscript copied by Newton directly addresses the issue of creating in-line design planes (Barker 1994). From my reading of this text, it describes the relative placement of first futtocks to floor timbers shown in Figure 49h. Furthermore, this is the relative arrangement of floor timbers to futtocks that is common within the complete double framing of the eighteenth and nineteenth centuries in European and American shipbuilding (Murray 1765:173–174; McKay 1839:48). NEXT
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