In another thread, Robmill0605 asked about methods for making up a set of plans from an old lines drawing with no offsets. I mentioned that I use FREE!ship / DELFTship to do the job, and he expressed an interest in a quick tutorial.
There are many ways to resurrect an old linesplan, of course, and each has its advantages. It can be done on the drafting table, with dividers and a scale rule; and any decent CAD program can be used to line up splined curves against a background drawing.
I'm partial to FREE!ship / DELFTship for three reasons. First, it's extremely quick. I find I can take a linesplan to a finished model in less than half an hour (although, if I want to, I can spend much longer fairing and fine-tuning, afterwards). Secondly, in addition to drawing up the lines & providing offsets, it renders the hull as a 3D model that can be inspected from all angles, or exported to full-featured 3D rendering program like Rhino or Blender. Lastly, various versions of the program are available a low cost (or no cost at all).
In the examples below, I'm using DELFTship Pro, but most of the procedures I describe are nearly identical on FREE!ship 2.6 (the last stable version of FREE!ship produced by the original developer, Martijn Van Engeland). A free version DELFTship (with some features disabled) is available here: http://www.delftship.net/ . FREE!ship 2.6 is available here: http://www.softpedia.com/get/Science-CAD/Freeship.shtml
I'll use the Mermaid sailing canoe as an example, because (as far as I know) the lines are available but the offsets are not.
The Mermaid sailing canoe was something of a legend, in her day. She was designed in 1913, for the express purpose of defeating the Canadian Ralph Britton, who had won every event in 1912. Leo Friede of New York asked W. F. Stevens to design a racing canoe that could beat Britton.
As F. H. Froling put it in 1921:
Friede's Mermaid remained a formidable competitor for the next two decades, giving Uffa Fox's Valiant / East Anglian stiff competition for the American canoe championship of 1934.Stevens found no easy task before him, but his genius asserted itself, and the result was the "Mermaid," a perfect creation from the viewpoint of naval architecture. In the trial races, to the astonishment of all, the "Mermaid" outsailed a fleet of the fastest canoes of the American Canoe Association.
Mermaid's lines were reproduced in Schoette's Sailing Craft (Macmillan, 1937), as follows:
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