Basically, if your mast
is more than 40% of LWL aft, it’s a cutter
A sloop is defined as a yacht whose mast is somewhere between stations 3 and 4 in the 10 station model of a yacht. This definition places the mast with two thirds of the vessel aft and one third forward.
A cutter is defined as a yacht whose mast is aft of station 4. Ascertaining whether the mast is aft or forward of station 4 (what if it is at station 4?) is difficult unless you have the design specifications. And even a mast located forward of station 4 with a long bowsprit may be more reasonably referred to as a cutter.
The usual method of referencing the stations is for station 0 to be at the point where the profile line in the side view crosses DWL at the bow and station 10 at the point where it crosses at the stern. The stations between are equally spaced, giving a station spacing of 10% of waterline length.
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