This question for anybody.... so I'll tack it on here...

How does one measure the waterline length of a Cathedral hull? Mainly
wondering about how to deal with the bow area.

Rick

On Fri, 7 Apr 2006 19:54:49 -0700, "Tom Dacon"
Tom-at-dacons-dot-com-nospam wrote:

Most people use "length between perpendiculars" (LBP). This is the
horizontal distance (parallel to the water's surface) between the closest
points on the ends of the boat where you could drop a plumb bob and have it
hit the water with the cord touching the boat. This doesn't include spars
such as bowsprits and boomkins. You'd use the stem, ordinarily, and the
aftermost point on the deck of the boat, including any cap rail but not
including extensions like boomkins.

That's what most people mean when they say LOD (length on deck). Length
overall (LOA) includes the spars, meaning sprits and boomkins, sometimes
also called "sparred length".

In the old days (before, say, the first world war), the waterline length was
what they used when they said how big the boat was. So a 30-footer would
have been 30 feet on the waterline. The New York Thirtys were thirty (more
or less) on the waterline, the New York Fortys were forty feet, and so on.

Without knowing what your boat's profile looks like in detail, it sounds to
me from your account like it's 23' 9".

But really ... my own boat is 40' 3" between perps. When I bought it I was
told it was 41', so that's what I tell people when they ask. When I haul it
out in a self-service yard, I say it's just under 40', since a couple of
yards I've hauled at in the past used 40' as a dividing line for daily
charges. I'd call your bateau a 24-footer.

Tom Dacon

"David Manthey" wrote in message
.. .
Is there an official way to determine the length of a boat?

For instance, I am captain of a wooden bateaux that the builder
claimed was 23' long. Measured from the very rear of the sternpost to
the very forward of the stem, it is 23' 9". Measured at the height of
the gunwale and including the stem and stern posts, the boat is 23'
0'. Exclusive of the stem and stern posts, the boat is 22' 6". The
typical 'fullen laden' water line is 21', while the length along the
bottom (it is flat bottom, so has no keel), is 19' 6".

So, my questions a (a) when telling someone the length of the boat,
which number do I use, and (b) has there been any standard on this
over time?

Thanks much.

- David
David Manthey

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