In terms of having the labels and marks visible as aids or guides in the assembly of the hull, the open faces of these timbers would be the only logical choice for their placement. However, the motivation for aligning the open faces of the floor timbers and second futtocks was not to create a nice continuous face for labeling. I am convinced this was done to create a design plane for drawing the frame shapes, from which the procedure for beveling the timbers would be consistent throughout the length of the vessel.
Bevels are either acute, under bevels, or obtuse, standing bevels, depending on whether they are measured from the after or the forward face of a timber relative to the midship station. Regardless of the shipbuilding tradition, the switch in timber arrangement within a frame relative to amidships reflects a desire to keep the type of beveling for a specific category of framing timbers (e.g., floor timbers, first futtocks) consistent for both forward and after frames (Chapelle 1969:135–136; Pardey 1991:95). Cutting standing bevels necessitates projecting the angle of the bevel beyond the curve, and this requires greater accuracy in the predetermination of the bevel angles. Under beveling is simpler because it entails the removal of wood relative to the drawn-out curve on a framing timber. Drawing the frame shapes on the open face of the timbers oriented toward amidships would allow for the under beveling of these timbers.
With double framing, the problem with beveling from the open face is that this entails projecting the bevel across two layers of timber. As a result, there is less assurance that the backing timbers will have exactly the correct shape unless the beveling is extremely accurate. For this reason, in some shipbuilding traditions of the seventeenth century and in most by the eighteenth and nineteenth centuries, using the adjoining face for laying out the frames was preferred (Barker 1994:21–22; Murray 1765:165–174; Wilson 1873:145–147). Nonetheless, the characteristics of the beveling of frame VIIIIA suggest that, at least in the case of La Belle's surmarked frames, the labeled faces of the floor timbers and second futtocks were used as a drawing plane. While the treenails are centered on the after labeled faces of VIIIIA's floor timber and second futtock, they get progressively closer to the outboard edge the further forward they penetrate into the frame timbers. As Figure 14 shows, the treenails break out on the outboard surface of the first futtocks quite close to what would be the adjoining face. If the shipwright had drawn the frame curve on the adjoining face and laid out the bevels relative to it, the fastenings would have been more centered on this face.
The interrelationship of framing patterns, beveling, and design planes still needs to be further explored in the case of La Belle as well as in the history of ship construction in general. NEXT
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