Shoal vs full
 

Same boat, shoal draft vs regular keel

What would be the differences in pointing, reaching and running?
Any differences in rollover factor?
Differences in sea keeping abilities?
Thanks
Gordon

Shoal vs full
 

On 2007-04-17 20:43:11 -0400, Gordon said:

Same boat, shoal draft vs regular keel

What would be the differences in pointing, reaching and running?
Any differences in rollover factor?
Differences in sea keeping abilities?

Depends on the particular boat, of course, but the primary difference
is usually poorer pointing ability. slight improvement in reaching and
running, slightly more tender, usually about the same righting ability.

--
Jere Lull
Tanzer 28 #4 out of Tolchester, MD
Xan's new pages: http://web.mac.com/jerelull/iWeb/Xan/
Our BVI pages: http://homepage.mac.com/jerelull/BVI/

Shoal vs full
 

Jere Lull wrote:

On 2007-04-17 20:43:11 -0400, Gordon said:

Same boat, shoal draft vs regular keel

What would be the differences in pointing, reaching and running?
Any differences in rollover factor?
Differences in sea keeping abilities?

Depends on the particular boat, of course, but the primary difference
is usually poorer pointing ability. slight improvement in reaching and
running, slightly more tender, usually about the same righting ability.

Our boats were designed to be either shoal (4'11") or deep draft
(6'6"). The deep draft boats had the bottom 18" of the keel made of
concrete. The discussion among owners is about whether the extra
weight of 18" of concrete makes a difference in the amount of weight
in the keel. Some people contend that the mfg'er added some lead to
the boats which came from the factory as shoal draft.

One way to reduce the amount of tenderness of a shoal draft boat is to
reduce the sail area. For some reason, when they made the walkthrough
models of our boat, they made them all shoal draft with the taller
mast, and they are very tender. We had a lady on board who owned a
walkthrough model of our boat. We have the shoal draft and a shorter
mast (8 feet more or less shorter - her boat had a 65 foot mast and
ours is less than 58 feet). She commented about how much less of a
problem our boat was to steer.

Shoal vs full
 

On Apr 17, 8:43 pm, Gordon wrote:
Same boat, shoal draft vs regular keel

What would be the differences in pointing, reaching and running?
Any differences in rollover factor?
Differences in sea keeping abilities?
Thanks
Gordon

Heard some interesting interviews with Ted Brewer recently, and he
also wrote a great article for Good Old Boat magazine. He noted that
all sail boat designs are effectively compromises. There are some
great calculators of boat stability (Google "sail calculator") and
boats rate differently for many different aspects of sailing. If you
want more numbers than you can ever use, visit http:// www.johnsboatstuff.com
and download his sail boat data base.

Figure out where you are going to sail and the type of sailing you are
going to do, and recognize that even those of us persistently
committed to coastal sailing like to go fast (or at least make headway
on a light wind day). Then try out a variety of boats. Larry had a
great comment a while back -- nothing beats actually sailing a few
boats before you buy, and all of us are always looking for crew.

Steve Hayes