I think my boat, even on the bottom of the ocean, would
still sail better than a Mac 26 XM.


Scotty



"DSK" wrote in message
.. .
Maxprop wrote:
A cube of lead one inch per side will not necessarily
float with a cube of
floatation material of the same size attached.
Depending upon the type of
flotation material it might require more or less than a
1" cube to float the
lead cube.


Of course. The flotation has to be of sufficient volume &
density to bring the average specific gravity below 1.0

A point that is occasionally overlooked is that the
flotation also has to be structurally sound. I learned
this
lesson in practice, trying to install positive flotation
on
the cheap for an old racing class boat.



... "marketplace" and "Engineering" are usually two
viewpoints in
conflict.



Engineers, fortunately or not, work for the same
companies that also employ
the marketing gurus. While their philosophies may
differ radically, the two
disciplines are not mutually exclusive.


Sure. Occasionally you see both talents combined in the
same
guy. But just because a product won't sell profitably,
that
doesn't mean it isn't possible or even practical.



From a more practical standpoint of a useful cruising
boat, then you (as I
believe you were driving at above) all you need is a
flotation volume
equal to the difference between the boat's volume of
material and the
immersed volume needed to float that weight. I've worked
out such figures
for a couple of production boats and the answer is that
the volume of the
seat & berth cushions is pretty close to enough.


If I'm interpreting you correctly, that would allow a
capsized vessel to
float with virtually nothing above the water level.


At minimum, yes. But that wouldn't serve much purpose
other
than to make the recoverable after an accident, at which
point it would be worthless... no value to the crew, who
would still need a survival craft, and no value in the
marketplace. So that is not a good enough answer, which is
why I then said:



Of course, you need a safety margin, and that volume
needs to be both
*secure* and also distributed in such a way that the
boat floats in it's
proper attitude (ie not bow pointed down, or leaned over
45 degrees) & has
some stability.


. . . and at least some of the boat out of the water
and able to support
the maximum allowable crew complement. Boston Whaler is
renowned for this.


Definitely agreed.


I'd think a life raft would suffice if safety were the
only consideration.

Depends. The whole boat is more desirable than a life
raft.
Otherwise why have the boat, why not just cruise in the
life
raft in the first place?

It's a bit more of a challenge to build a boat that would
be
liveable and operable (even sailable) after severe
flooding,
but it's certainly possible. And I think, for some types
of
sailing, it's highly desirable.

I can't believe that there are still some centerboard
racing
classes that are not self-rescuing; some don't even have
positive flotation. WTF are they thinking?



Show me where I suggested that it be mandated that all
boats be required
to have positive flotation.


Easy there, Doug. I didn't say you did. That nanny
comment was mine, and
intended as a gentle elbow to the ribs.


Ah so, got it now.


Heck, the Mumm 30 would be real easy to put positive
flotation in. Not
much of a premium on cabin space, anyway.


The last Mumm 30 on which I crewed was owned by a sailor
who bitterly
complained about the inability of his boat to carry
adequate spares due to
the limited interior volume. Then again he believed
that nothing short of a
dozen sails was minimal in order to be prepared for any
sort of weather.
When I pointed out that those extra sails add lots of
weight, he poo-poo'd
the idea. Of course he never finished all that well,
either.


Sounds like he didn't have his priorities quite in order.
Well, it's his boat, his priviledge.

I think J-24s should have positive flotation. AFAIK the
Soling class now requires it (sinkings were fairly common
back in the day); not sure if the Etchells does. The 1D-35
and the new Farr 36 both have positive flotation. A Mumm
30?
A bit harder to sink but still possible...




The bottom line is that positive flotation is
*definitely* possible... as
I said, all you need is to fill the boat with foam up to
the static
waterline, and put your cabin floor over that. Or apply
that same volume
of foam to a carefully distributed set of unused voids &
crannies.


Or at least part of that flotation foam could be used as
hull stiffening,
ala Boston Whaler. My sailboat has an Airex foam core
between the hull
laminates. It's not particularly thick, but it does add
a substantial
amount of rigidity, and the builder claimed it even
provided enough
flotation effect that it wouldn't take a lot of
additional flotation
material or air bags to make the boat float in event of
capsize. Not that I
exactly care one way or the other.


True.
Some people hate foam core, though.



Is it desirable? Depends. If I were going to do a lot of
ocean crossing,
making passages along rough & rocky coasts, etc etc, I
would want it.


Why? If making open-water passages, what would you
achieve by keeping your
boat afloat. A capsized cruising sailboat a thousand
miles from anywhere is
a total loss, floating or not.

Because if I went to the effort, the boat would not only
remain afloat but have a good positive range of stability
&
reserve bouyancy... ie be operable and liveable after
severe
flooding...


... Near shore may be
another matter entirely, but along the "rocky coast" I'm
not sure there
would be any value either.

Not much sense in making sure theboat remains afloat if
it's
going to be smashed to pieces, sure. But if all the pieces
still float, the people have a better chance IMHO.


... Here in
the Great Lakes, or on Pamlico Sound, a floating boat
could be salvaged.


Shucks, in Pamlico Sound... or many places along the
Chesapeake... you could just wade ashore. The boat
wouldn't
sink very far.





I asked Ted Gozzard about positive flotation at Strictly
Sail in Chicago a
few years ago. He just laughed at me, as if I were some
idiot. I asked him
to elucidate, to which he responded, "See those little
cat boats over there?
(18' Marshall) That's what you want if you want
positive flotation." I
said I wasn't personally interested in positive
flotation, but was asking
the question hypothetically. He just laughed again and
turned away. I'm
not quite sure how to interpret that, but it would
appear that he regarded
positive flotation as a non-issue. FWIW.


For him, it almost certainly is. I'm not surprised he's a
bit of a reactionary (I mean, look at his boat designs)
but
I'd be surprised if he didn't have a pretty good grip on
the
practical issues involved. But then, talking to boat
designers at boat shows is often a futile endeavor...
they're there to sell boats.

DSK

Scotty wrote:
I think my boat, even on the bottom of the ocean, would
still sail better than a Mac 26 XM.


Don't brag about it.

DSK

On Mon, 13 Nov 2006 03:34:55 GMT, "Maxprop"
wrote:


"Goofball_star_dot_etal" wrote in message
.. .
On Sun, 12 Nov 2006 11:48:01 -0500, DSK wrote:

Positive flotation probably wouldn't be offered by manufacturers
voluntarily.




It already is, by several. Sadler & Etap spring to mind.



http://www.mikelucasyachting.co.uk/story.htm

Interesting reading. It sounds as if the 26 was able to maintain decent
freeboard when flooded, but I'm wondering if the larger boats would do
similarly?

I imagine so but don't know. There is no obvious hint looking inside
that space has been lost to bouyancy. You just get the general
impression that they are proper boats not caravans.

Nice looking boats.


Not bad. In order of most to least pretty I would say 32,34,25,29,26
but they are all quite boaty looking. Most here are bilge keel (drying
harbours) and of average speed but the 34 is a fairly full fin keel
and quite quick. On the 34 we went close-hauled though some biggish
(2-3m) overfalls with the tide behind us at about 9kts SOG like a
knife through butter.. Unfortunately this was too wet for the camera
but earlier and much flatter you get the idea how well it slices
through he
http://www.wareing77.plus.com/movies/Barbadee_video.htm (repeat:-))
If that does not work poke around:
http://www.wareing77.plus.com/movies/ for IMGP0733.xxx
There are a couple of pictures of the 34 in here, I think:
http://www.wareing77.plus.com/images/ but I have lost track of what's
what.
There is a nice pic of a friend's 26 here (jasmin):
http://aberystwythharbour.co.uk/

"DSK" wrote in message
.. .


Depends. The whole boat is more desirable than a life raft. Otherwise why
have the boat, why not just cruise in the life raft in the first place?

It's a bit more of a challenge to build a boat that would be liveable and
operable (even sailable) after severe flooding, but it's certainly
possible. And I think, for some types of sailing, it's highly desirable.

I would agree with the paradigm you offer. I must admit I'm not aware that
a vessel of decent size and cruising capacity (volume and mass) could meet
those parameters. I'd be interested, and I suspect others would be as well.

I can't believe that there are still some centerboard racing classes that
are not self-rescuing; some don't even have positive flotation. WTF are
they thinking?

I wasn't aware that some still don't have self-rescuing capability. Snipes
went through a decade-long metamorphosis from positive flotation to
self-rescuing (self-turtling, in the early iterations) as a result of class
rule changes, and I assumed most other smaller racing classes had similar
requirements. Considering the nature of the sailing in such classes, it's
doubly surprising.

Sounds like he didn't have his priorities quite in order. Well, it's his
boat, his priviledge.

I wondered why he had constant crew turnover while other boats sailed with
many of the same crew for years. I spent three weekends with him and was
told I was with him about as long as anyone. I jumped ship and raced with a
couple of guys for whom an extra pair of gloves were an unacceptable weight
penalty.


True.
Some people hate foam core, though.

I'm curious--why? It provides hull rigidity, it's closed-cell meaning it
won't absorb water like end-grain balsa or ply, and it's temperature stable.
What's the downside?

Because if I went to the effort, the boat would not only remain afloat but
have a good positive range of stability & reserve bouyancy... ie be
operable and liveable after severe flooding...

That would be preferable to a life raft, yes.


Shucks, in Pamlico Sound... or many places along the Chesapeake... you
could just wade ashore. The boat wouldn't sink very far.

After the wind tide receded from one of the hurricanes, I saw a photo of
people walking miles from shore on the Sound. Amazing. We, um, don't get
that here.

For him, it almost certainly is. I'm not surprised he's a bit of a
reactionary (I mean, look at his boat designs) but I'd be surprised if he
didn't have a pretty good grip on the practical issues involved. But then,
talking to boat designers at boat shows is often a futile endeavor...
they're there to sell boats.

I agree that he should have had a fair grasp of the positive flotation
issues and details, but he could have been a bit more affable by explaining,
at least briefly, why he found it laughable. I decided then and there I'd
never own a Bayfield or a Gozzard, if only because he was a jerk. g

Max

I can't believe that there are still some centerboard racing classes that
are not self-rescuing; some don't even have positive flotation. WTF are
they thinking?


Maxprop wrote:
I wasn't aware that some still don't have self-rescuing capability.

Yep. Flying Scots probably the most obvious. Lightnings are
only 'self-rescuing' if one puts a very loose interpretation
on the term, and the crew is skilled & strong.



.... Snipes
went through a decade-long metamorphosis from positive flotation to
self-rescuing (self-turtling, in the early iterations) as a result of class
rule changes, and I assumed most other smaller racing classes had similar
requirements. Considering the nature of the sailing in such classes, it's
doubly surprising.


Inertia and old-fogeyism. At least we don't have splintering
gaffs hurtling around any more.



Some people hate foam core, though.


I'm curious--why?

Because, man, it's CORED! It isn't 3 inch thick solid
fiberglass like Mamma used to make... you know, back in the
good old days when they didn't really know how strong the
stuff was.


It provides hull rigidity, it's closed-cell meaning it
won't absorb water like end-grain balsa or ply, and it's temperature stable.
What's the downside?


It can delaminate if overstressed or not bonded correctly in
the first place. It needs to be cut back in the way of any
thru-bolted fittings.

Aside from that, it's too light, when everybody knows that
boats should be heavy!



..... I decided then and there I'd
never own a Bayfield or a Gozzard, if only because he was a jerk. g


I might own a Gozzard if they weren't so flamingly
overpriced. To me, Bayfields seem like just a more
piratey-looking version of a Morgan Out Island.

I've met a lot of boat designers over the years, the boat
show is not a good place to talk intelligently to them.
They've just been thru a wringer for the past X weeks (maybe
months) getting ready and now they're all jazzed up to try
and move product. A few notable exceptions were Roger
Dongray, the Cornish Crabber/Shrimper designer, and Jerry
Douglas the chief designer for Catalina (he introduced me to
his friend Frank Butler, whom we've met on several
successive occasions). However I'd like to note that while
Jerry Douglas seemed quite interested in the Johnson 18 and
came up with several ideas on the boat, Catalina/Capri never
implemented any of them and let the class die.

DSK

"DSK" wrote in message
...
Maxprop wrote:

Some people hate foam core, though.


I'm curious--why?

Because, man, it's CORED! It isn't 3 inch thick solid fiberglass like
Mamma used to make... you know, back in the good old days when they didn't
really know how strong the stuff was.

Ah, gotcha.

It provides hull rigidity, it's closed-cell meaning it won't absorb
water like end-grain balsa or ply, and it's temperature stable. What's
the downside?


It can delaminate if overstressed or not bonded correctly in the first
place. It needs to be cut back in the way of any thru-bolted fittings.

Aside from that, it's too light, when everybody knows that boats should be
heavy!

Even with the foam core my boat has a disp/length ratio of over 400. I hate
to think what it might have been had the hull been 1" solid FRP.


I've met a lot of boat designers over the years, the boat show is not a
good place to talk intelligently to them. They've just been thru a wringer
for the past X weeks (maybe months) getting ready and now they're all
jazzed up to try and move product. A few notable exceptions were Roger
Dongray, the Cornish Crabber/Shrimper designer, and Jerry Douglas the
chief designer for Catalina (he introduced me to his friend Frank Butler,
whom we've met on several successive occasions). However I'd like to note
that while Jerry Douglas seemed quite interested in the Johnson 18 and
came up with several ideas on the boat, Catalina/Capri never implemented
any of them and let the class die.

I met Frank Butler at a show about twenty years ago. He was amiable,
informative, excited about is products and eager to speak with potential
customers. A few years ago I heard him speak at a seminar in Chicago. He
was cynical, obnoxious, and appeared depressed. Perhaps success isn't all
it's cracked up to be. ??

Max

This thread just keeps on going, and going, and going... I think that I
have found the immediate remedy to my quest. I think that I will join
the Harbor Island Yacht Club. I have a few friends that sail there and
all enjoy it. I'll have access to good instruction and several
different boats. What a better way to start out. I can also buy a
small motor boat for putting around when we go camping to keep the
family happy. Win-win.

Carl

"CJH" wrote in message
...
This thread just keeps on going, and going, and going... I think that I
have found the immediate remedy to my quest. I think that I will join the
Harbor Island Yacht Club. I have a few friends that sail there and all
enjoy it. I'll have access to good instruction and several different
boats. What a better way to start out. I can also buy a small motor boat
for putting around when we go camping to keep the family happy. Win-win.

Sounds reasonable. Nothing quite like the experience and opinions of
experience sailors to help a newcomer along. But bear in mind that a lot of
what you'll hear at the HIYC will be opinions, and opinions are just
that--not facts.

Sounds one hell of a lot like alt.sailing.asa, dunnit?

Small motor boat is a great idea. I have a Boston Whaler Rage (15' jet
drive) as a play boat to fill in on those sultry, windless days when raising
sails for no good reason, etc., is a pain. Only problem is that everyone
else on the dock wants to use it.

Mac . . . er, Max

Aside from that, it's too light, when everybody knows that boats should be
heavy!


Maxprop wrote:
Even with the foam core my boat has a disp/length ratio of over 400. I hate
to think what it might have been had the hull been 1" solid FRP.


It should change the D/L ratio because it shouldn't change
the designed displacement. It would however reduce the
ballast and increase the average specific gravity (as Jeff
noted).

These discussions go 'round & 'round with the crab-crusher
folk who think a boat should be like a steam-roller. Most of
them can't seem to realize that a boat hull has only a given
amount of immersed volume, and that increasing weight for no
purpose only subtracts from the weight which can be used to
serve a purpose.



Maxprop wrote:
I met Frank Butler at a show about twenty years ago. He was amiable,
informative, excited about is products and eager to speak with potential
customers. A few years ago I heard him speak at a seminar in Chicago. He
was cynical, obnoxious, and appeared depressed. Perhaps success isn't all
it's cracked up to be. ??


He has some health problems, the last time we met him (about
4 or 5 years ago) he was more eager to speak about health
issues with my wife than about boat issues with me. But I
still found him to be a nice guy, don't know about dealing
with the public. Another possible factor is that he's become
more of a CEO than a boatbuilder, and he may find that a lot
less fun than, say, Michael Dell does.

Fresh Breezes- Doug King

CJH wrote:
This thread just keeps on going, and going, and going... I think that I
have found the immediate remedy to my quest. I think that I will join
the Harbor Island Yacht Club. I have a few friends that sail there and
all enjoy it. I'll have access to good instruction and several
different boats. What a better way to start out.

Can't really think of one, myself. The opportunity to get
first-hand experience on a wide variety of boats is invaluable.

The one bit of advice I would offer is, if you are solicited
to join a racing crew, ask discretely around the club to see
if the skipper is a screamer. If by some chance, you do get
shangaied into racing (or sailing at all) with a nice guy
who suddenly turns into a screaming butt-head, please don't
conclude that all racers (or sailors of that type boat) are
like that. This is a common situation even though screamers
are a small minority, but they drive away good crewand thus
are always recruiting.


I can also buy a
small motor boat for putting around when we go camping to keep the
family happy. Win-win.


It doesn't have to be fancy, those "tin skiffs" are very
practical and a lot of fun.

DSK