Photo 39. The first step in plank tapering
Copyright © 2006, James Allen
Transposing measuring points to a plank in place on the hull

Hull planking strakes have to be tapered in width to allow for the fact that the distance between the keel and the gunwale varies at any given point along the hull due to the shape of the hull. The notional aim is to have the same number of planks side-by-side all the way along the hull, but in reality most hull shapes require some extra short planks to be inserted, particularly at the stern. The reason for this is that planks should never be tapered to a width less than half their full width.

Entire books are written about hull planking techniques, and these should be consulted before attempting the final layer of planking on a model. The instructions for hull planking that come with model kits are generally inadequate at best, or completely wrong.

Here Robine is laying a plank in position on the hull butted up against its neighbour. She will then mark the new plank from guidelines she had previously drawn over the first layer of planks. These guidelines typically line up with the hull bulkheads, but can be spaced along the hull at any convenient distance. These marks are used to adjust the width of the plank where required using proportional dividers, a proportional gauge graph, or a direct calculation. Since proportional dividers are expensive, Robine is using a proportional gauge graph for this project that she has constructed herself (see next image).