The shipwright would have to transfer the surmarks onto the design frames, in a temporary or permanent fashion, because these are the only points at which quantitative information would be available for the change in longitudinal curvature. This information would be essential for laying out the bevels in order to fashion the complete frame.
The conclusion that these timbers were labeled on the ground accounts for the fact that some of the labels are upside down (e.g., IIIA in Figure 3). The shipwright simply stood on the wrong side of the timber when carving this label. Once the floor timbers and second futtocks were fashioned and placed in their proper alignment, the timbers for the first and third futtocks would be shaped to match and scarfs cut in the floor timbers. The frame pieces would have then been laid out on the ground in their correct alignment and bored for fore-and-aft fastenings. The resulting holes are more or less perpendicular to the frame surface because the shipwrights bored from above. Thus the overall perpendicularity of the fastenings on the mould frames is a consequence of the design and construction sequence and not a requirement in itself.
I suspect the final beveling was done on the assembled frames, and the bevels were laid out as underbevels from the surmarked frame faces. This would explain why the fore-and-aft fastenings tend to be centered on the surmarked faces and exit close to the outboard edges on the opposite side of the frames. This feature is much more pronounced on frames with greater bevel angles, such as VIIIIA. I am uncertain to what extent, if any, the bevel angles were accounted for in the shaping of the individual frame timbers or in the relative placement of the two layers of framing timbers for each frame. The proposed beveling procedure would explain why frame VIIIIA was first assembled with treenails. This would be a prudent precaution if this frame's large bevel angles were being projected across two layers of timber.
There is no direct evidence indicating whether or not frames XIIA, XVD, and XVIIID had surmarks, since these would have been above the level of preservation. However, the reconstructed design procedure shows that defining the shapes of these frames was as integral to La Belle's design as defining the shapes of the frames with surviving surmarks. Overall the design method determines the shapes of every third frame along the full length of the floor diagonal from and including XIIA to XVIIID (Figure 20x). However, the treenails that were cut through and exposed on the outboard face of frame VIIIIA indicate that the shipwrights may have had difficulty determining the beveling of the design frames toward the ends of the vessel. It is possible that the beveling of some of these frames was finished with the aid of actual ribbands. Nonetheless, the overall shapes of these frames were determined during the design stage and once raised they defined the basic shape of the hull. NEXT
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