Karl and Fuzz, for the Feather Pram, to accurately draw the shape of the moulds on sheets of ply from which the moulds will be cut, you need to take the following steps:
1. Understand what the supplied full size patterns show.
Referring to the first pic, a full size cross-section of a theoretical rounded hull at stations 2, 3 and 4 are shown.
Station 3 is shown only as a curved line, along with the points along the curve where the individual clinker plans will land (plank lands).
Section 4 shows the layout for 1/5” thick plywood planking, whereas Section 2 shows the layout for ¼” thick solid timber planking.
Referring to sections 4 and 2, and working from the centreline towards the gunwale, it can be seen that a mould cut precisely locate the
planks, needs to be saw-toothed.
2. The next pic shows how I marked up the cross-section of all planks on a copy of sections 2, 3 and 4. This was necessary to reveal accurately
the necessary saw tooth shaped mould at each section. The plank lands are also drawn accurately, at right angles to the relevant plank (not
yet done for #2 in pic) .
The baseline, centreline, design water line and saw-tooth shape of each mould can then be transferred from plan to plywood using a sharp
point pushed through the plan into the plywood.
The positions of the plank lands are transferred as lines extended at right angles from the plank face. These lines will later be cut into the
mould.
3. The next pic shows a cut out mould. The saw tooth shape is more pronounced towards the gunwale and the keel. Each plank should sit
precisely on the flat surface of each mould, and its inboard edge should but up against the sawtooth ‘rise’ . The edges of the mould’s indented cut-out define where the plank lands are.
Hope this makes sense.

Currently building Jacques Mertens ST21 "Skinnydip". Boating adventures: Splash testing and using 'Skinnydip, as a basis of further building refinement; Adams 44’ sailing sloop "Great Sandy" (cruising and maintaining); Iain Oughtred Feather Pram "Mini Dip" (building); Jacques Mertens R13 "Wood Duck" (built and due for maintenance).