Originally Posted by popberger8
I'm afraid that I do not understand the question. Could you explain shear and what the rise of shear means to using the boat?
My error in spelling of 'Sheer' (Being a Scot, shear being a Scots word derived from shearing sheep)
The nautical term "sheer" is "a measure of longitudinal deck curvature in naval architecture"
So that the question is rephrased, I have extracted the picture of a friend's Whitby 42 Ketch and added some lines to illustrate.
Whitby Water Line.jpg
But first another nautical term:-
Gunnel (from Gunwale)
the upper edge of the side or bulwark of a vessel.
the sheer strake of a wooden vessel; the uppermost strake beneath the plank-sheer.
line is parallel with the water. Above the Red
line is a barge board, the top edge of which is the line of gunwale.
arrow is the point at which the gunwale line rises to the stern and to the bow.
line represents the horizontal level of the sea. Above the Green
line is the existing painted Black
The forward Green
arrow marks the position (on this boat) where the Black
line starts to curve following the sheer. The aft Green
arrow marks the position where the Black
line starts to rise following the sheer of the gunwale.
-- The reason for not painting a dead straight line, is to correct the illusion that the line droops towards both ends of the boat.The sweep or sheering of the boot and the painted water line solves this problem. In addition, a dead straight boot will show the slightest trim imbalance, but a swept boot and bottom line cures that.
So to return to the question first posed :-There is a formula/e for determining the correct positions of the Red and Green ARROWS. Where can I find it?
To the second part of your Question -
"what the rise of shear means to using the boat?"
In simple terms:- the higher the bow, the dryer the boat.