In the case of La Belle, all the frames bear location labels, thus these labels do not distinguish the design frames. Similarly, all of La Belle's frames have similar scarfs between the floor timbers and first futtocks. It is the presence of surmarks and the differing angles of the fore-and-aft fastenings that primarily distinguish the design frames.
A partial double framing arrangement such as La Belle's could have been introduced for purely structural reasons, but this new framing arrangement is also integral to the use of a new design system on La Belle. As was discussed in Part I, the design with diagonals necessitates a continuous design face, and there is strong evidence that La Belle's mould frames were laid out on and underbeveled from the surmarked open faces of the floor timbers and second futtocks. The shapes of the component timbers in this partial double framing arrangement no longer parallel the shapes of the overlapping design templates used with Mediterranean moulding (Figure 49k). Therefore, there is no correlation between any scarf features and the surmark locations, and the surmarks were not necessarily used to assure the proper alignment of the two layers of timbers that compose each individual frame. The first and third futtocks simply serve as backing timbers to maintain the shape-defining floor timbers and second futtocks in their proper alignment.
Rising of the Templates
The interrelationship between framing patterns and design faces is illustrated with drawings that only depict the narrowing of the hull. This made creating the drawings far simpler, but in reality all known applications of Mediterranean moulding define both narrowing and rising adjustments of the floor at the tail frames.
In Figure 49m the tail frame is elevated the distance zz above the keel. Note that the small additional distance between zz and the floor template is the deadrise at the midship frame as shown in Figure 49a. As with the narrowing of the hull, this total rising distance had to be subdivided into offsets for a curve that determine how much the template has to be elevated at each design frame station. These offsets are marked on a separate rising board that is used in conjunction with the templates (Figure 49a, m–r).
Diagonals in Mediterranean Moudling
As with the narrowing scale, a curve drawn through the rising offsets at the centerline would not define an actual curve on the hull. It is for the practical reason of being able to adjust the master template on the timbers that the narrowing and rising increments for the lower hull were applied relative to the centerline. In fact, the narrowing and rising shifts in Mediterranean moulding can be conceived as diagonal shifts at anchor points such as the bilge surmarks. NEXT
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