Bryan wrote:
wrote in message
oups.com...

Bryan wrote:

"JR North" wrote in message
...

It's the inclusive angle of the hull at the transom, from keel to
chine.
JR

Bryan wrote:


What does dead rise mean?
My boat has a 19 degree dead rise.


--
--------------------------------------------------------------
Home Page: http://www.seanet.com/~jasonrnorth

Thanks, but that didn't help. Want to try a simpler or more illustrative
explanation?


If your boat were a log raft or a sheet of plywood, it would have zero
deadrise.
The perfectly flat bottom would not rise up above a horizonal line
drawn below the boat.
The chines (edges of the bottom, sort of) would rest on that horizontal
line just like the keel.

As the bottom assumes a "V" shape, an angle is formed between the point
where the keel meets that horizontal line and the chines. If there were
almost no angle at all, you might have a 5-degree deadrise. As the
angle gets more pronounced, so does the number of degrees "deadrise"
increase. Essentially you're measuring how steep or shallow the "V" is
under the hull. Because this measurement will vary along the length of
the boat, it is customarily taken at the transom, or stern.

Boats with more deadrise tend to handle rough water better. Boats with
flatter bottoms will plane more quickly, but will pound and slam more
easily in a seaway and are less desirable when conditions are a bit
grumpy.



Thank you. Nice answer. For perspective, where does 19 degrees fall on
the scale. Is it very little dead rise or a lot of dead rise or right in
the middle? Maybe it's a question that has too many factors to answer, but
I'll ask anyway.



It depends on the length and purpose of the boat. 19º +/- 2º is pretty
common for bluewater boats in the 18' - 25' range.

As Chuck said, more deadrise will tend to handle rough water better. If
the boat is very long, the deadrise is less important. Look here for
some more info...

http://powerboat.about.com/od/mainte.../aa012403b.htm

Dan