Re: A Cold-Water sailboard
John,
that LIVELY by Uffa Fox does have a nice profile
http://www.woodenboatstore.com/prodinfo.asp?number=150%2D045A few
Bolger sharpies approach that sheer line profile; and that above the
waterline profile, especially the bow, can be seen in some Michalak
boats.
FWIW, more thoughts about Cold-Water Sailboard. I think the bottom of
CWS not to be flat toward the bow, it is not like a flat iron skiff
nor the Chapelle "rule". It does have a curve that is just a bit
gentler than that of the run aft. Whichever profile view of it I look
at I'm sure my eye is tricked by either the sheer, the sloping deck,
or the colouring. Unless the page is firmly held flat to the desk the
curve of the page towards the book spine accentuates the optical
uncertainty, I'm sure.
Bolger has done typical flat iron sharpie bottoms, such as for
Cynthia J, and Storm Petrel, and of course many of his very own
potbelly sharpie bottoms. The latter to deliver improved displacement
performance based on his flow theory. Well known Bolger designs
incorporating either of these two bottom types IMHO have never been
meant for boats that are meant to plane most of the time. Exceptions
like the scooners will plane, but any speed for most of these is
based on either outright length, or, especially, their relative
lightness that allows a considerable amount of S/L rule (wave making)
cheating, but mostly not true planing.
Sailboards plane. Thats what they're meant to do easily and with as
little effort as possible. The bottom of CWS is quite similar to that
of DYNAMITE SAILBOARD. Both boats have plumb sides. The bottom
profile curves are quite alike, and are a bit flatter forward. Both
boats, like sharpies generally, are meant to be sailed with the bow
trimmed just above the waterline. The Dynamite has a bow half angle
of close on 10degrees, and CWS has a half angle of near 15degrees.
The bottom loadings (remember they're plumb sided) are very similar
too when sailed as designed with single crew: the Dynamite bottom is
loaded at approx 9lbs/sqft, and the CWS just a little more at about
9.3lbs/sqft. The draft in each case is aproximately 2in.The L/Bs are
significantly different, but, at a guess, the relative width of CWS
may support earlier planing.
A hundred or so boat designs after CWS it seems PCB again went
through some very similar thinking when he considered the design of
Dynamite. He thought about lightness, free-flooding wells, flare, and
particularly he thought about the bow, eg "I thought of giving the
sides a slight flare. Using the same straight side planks, this would
have swept the bow higher. One's first thought is that this would be
better in choppy water [per sharpie theory?], but I'm not so sure. I
was sure that the low bow would be faster in smooth water." (30-Odd
p11)
It occurs to me that PCB would not be happy in later times with the
peak sprit geometry on CWS. He wrote of FELUCCA, which came about
fifty designs after CWS "(Thomaston Galley mainsail used on
Felucca) ...includes the mistake of making the peak sprit too short
and its snotter not powerful enough. The result is that the peak
sags, to the great detriment of her windward work. I've repeated this
mistake about seven times and have sworn a mighty oath that it won't
happen again." (DB p34) Then again the CWS rig may be ok, as rather
than windward work the crew may be happy just to reach back and
forth - fast. Then again, perhaps, with a little jiggering, the sprit
sloop rig from FELUCCA could serve as a cruising rig on CWS? Also,
how about adding a sliding hiking seat?
Graeme
The below not particularly pertinent to these boats, but nonetheless
a little indicative.
CWS DYNAMITE DYNAMITE DYNAMITE LIVELY
"novice" "L-O-M" "LASER"
LOA ft 15.75 16 16 16 16
LWL ft 14.5 15 15 15 16
Beam ft 4 2 2 2 5.33
Displacement lbs 435 250 250 250 1073
Sail Area sqft 104 43 59 77 175
Displ/LWL 64 33 33 33 117
LWL/Beam 3.63 7.5 7.5 7.5 3
Hull Speed kts 5.1 5.19 5.19 5.19 5.36
Motion Comfort 7.09 9.98 9.98 9.98 11.08
SA to Displ *** 28.98 17.34 23.79 31.04 26.72
***
Capsize Ratio 2.11 1.27 1.27 1.27 2.08
Pounds/inch 207 107 107 107 305
Sailing category racer cruiser/racer racer racer racer
http://www.image-ination.com/sailcalc.html#2
SA to Weight 5.4 4.1 4.8 5.5 5.17
[Ratio = SQRT(SA)/(Displacement in lbs/64)^.3333 This calculation
provides a simple comparison of the upwind and downwind speed
potential of a given design.]
http://www.nwmarinedesign.com/srscript.htm
that LIVELY by Uffa Fox does have a nice profile
http://www.woodenboatstore.com/prodinfo.asp?number=150%2D045A few
Bolger sharpies approach that sheer line profile; and that above the
waterline profile, especially the bow, can be seen in some Michalak
boats.
FWIW, more thoughts about Cold-Water Sailboard. I think the bottom of
CWS not to be flat toward the bow, it is not like a flat iron skiff
nor the Chapelle "rule". It does have a curve that is just a bit
gentler than that of the run aft. Whichever profile view of it I look
at I'm sure my eye is tricked by either the sheer, the sloping deck,
or the colouring. Unless the page is firmly held flat to the desk the
curve of the page towards the book spine accentuates the optical
uncertainty, I'm sure.
Bolger has done typical flat iron sharpie bottoms, such as for
Cynthia J, and Storm Petrel, and of course many of his very own
potbelly sharpie bottoms. The latter to deliver improved displacement
performance based on his flow theory. Well known Bolger designs
incorporating either of these two bottom types IMHO have never been
meant for boats that are meant to plane most of the time. Exceptions
like the scooners will plane, but any speed for most of these is
based on either outright length, or, especially, their relative
lightness that allows a considerable amount of S/L rule (wave making)
cheating, but mostly not true planing.
Sailboards plane. Thats what they're meant to do easily and with as
little effort as possible. The bottom of CWS is quite similar to that
of DYNAMITE SAILBOARD. Both boats have plumb sides. The bottom
profile curves are quite alike, and are a bit flatter forward. Both
boats, like sharpies generally, are meant to be sailed with the bow
trimmed just above the waterline. The Dynamite has a bow half angle
of close on 10degrees, and CWS has a half angle of near 15degrees.
The bottom loadings (remember they're plumb sided) are very similar
too when sailed as designed with single crew: the Dynamite bottom is
loaded at approx 9lbs/sqft, and the CWS just a little more at about
9.3lbs/sqft. The draft in each case is aproximately 2in.The L/Bs are
significantly different, but, at a guess, the relative width of CWS
may support earlier planing.
A hundred or so boat designs after CWS it seems PCB again went
through some very similar thinking when he considered the design of
Dynamite. He thought about lightness, free-flooding wells, flare, and
particularly he thought about the bow, eg "I thought of giving the
sides a slight flare. Using the same straight side planks, this would
have swept the bow higher. One's first thought is that this would be
better in choppy water [per sharpie theory?], but I'm not so sure. I
was sure that the low bow would be faster in smooth water." (30-Odd
p11)
It occurs to me that PCB would not be happy in later times with the
peak sprit geometry on CWS. He wrote of FELUCCA, which came about
fifty designs after CWS "(Thomaston Galley mainsail used on
Felucca) ...includes the mistake of making the peak sprit too short
and its snotter not powerful enough. The result is that the peak
sags, to the great detriment of her windward work. I've repeated this
mistake about seven times and have sworn a mighty oath that it won't
happen again." (DB p34) Then again the CWS rig may be ok, as rather
than windward work the crew may be happy just to reach back and
forth - fast. Then again, perhaps, with a little jiggering, the sprit
sloop rig from FELUCCA could serve as a cruising rig on CWS? Also,
how about adding a sliding hiking seat?
Graeme
The below not particularly pertinent to these boats, but nonetheless
a little indicative.
CWS DYNAMITE DYNAMITE DYNAMITE LIVELY
"novice" "L-O-M" "LASER"
LOA ft 15.75 16 16 16 16
LWL ft 14.5 15 15 15 16
Beam ft 4 2 2 2 5.33
Displacement lbs 435 250 250 250 1073
Sail Area sqft 104 43 59 77 175
Displ/LWL 64 33 33 33 117
LWL/Beam 3.63 7.5 7.5 7.5 3
Hull Speed kts 5.1 5.19 5.19 5.19 5.36
Motion Comfort 7.09 9.98 9.98 9.98 11.08
SA to Displ *** 28.98 17.34 23.79 31.04 26.72
***
Capsize Ratio 2.11 1.27 1.27 1.27 2.08
Pounds/inch 207 107 107 107 305
Sailing category racer cruiser/racer racer racer racer
http://www.image-ination.com/sailcalc.html#2
SA to Weight 5.4 4.1 4.8 5.5 5.17
[Ratio = SQRT(SA)/(Displacement in lbs/64)^.3333 This calculation
provides a simple comparison of the upwind and downwind speed
potential of a given design.]
http://www.nwmarinedesign.com/srscript.htm
--- Inbolger@yahoogroups.com, "mannthree" <johnmann@...> wrote:
>
>
> Graeme,
>
> Thanks for the informative comments. What you say is probably
correct,
> but that hull shape still intrigues me. To me it seems different
from
> the other Bolger sharpie designs in that in profile, the depth of
the
> hull is fuller at the bow where the bottom is flat and then leads
back
> in a gentle curve to a decidedly shalower stern. I would be
> interested to here some of the more knowledgeable members of this
> forum comments on the handling and sailing characteristics of this
> type of hull. My initial impression was that it resembles Uffa
Fox's
> Lively sailboat (plans for sail from Wooden Boat Magazine). I
suspect
> that having volume in the bow may have something to do with it. The
> boat has a narrow beam and a very fine bow entry (sorry I haven't
any
> pics) so it would certainly push aside any waves, but maybe make it
a
> wet boat in a chop?? Anyway I reckon if you wanted to experiment
> cheaply, you could use the bare hull as a basic starting point (four
> sheets of ply) and tinker from there,
>
> Cheers,
>
> John
Graeme,
Thanks for the informative comments. What you say is probably correct,
but that hull shape still intrigues me. To me it seems different from
the other Bolger sharpie designs in that in profile, the depth of the
hull is fuller at the bow where the bottom is flat and then leads back
in a gentle curve to a decidedly shalower stern. I would be
interested to here some of the more knowledgeable members of this
forum comments on the handling and sailing characteristics of this
type of hull. My initial impression was that it resembles Uffa Fox's
Lively sailboat (plans for sail from Wooden Boat Magazine). I suspect
that having volume in the bow may have something to do with it. The
boat has a narrow beam and a very fine bow entry (sorry I haven't any
pics) so it would certainly push aside any waves, but maybe make it a
wet boat in a chop?? Anyway I reckon if you wanted to experiment
cheaply, you could use the bare hull as a basic starting point (four
sheets of ply) and tinker from there,
Cheers,
John
--- Inbolger@yahoogroups.com, "graeme19121984" <graeme19121984@...>
wrote:
Thanks for the informative comments. What you say is probably correct,
but that hull shape still intrigues me. To me it seems different from
the other Bolger sharpie designs in that in profile, the depth of the
hull is fuller at the bow where the bottom is flat and then leads back
in a gentle curve to a decidedly shalower stern. I would be
interested to here some of the more knowledgeable members of this
forum comments on the handling and sailing characteristics of this
type of hull. My initial impression was that it resembles Uffa Fox's
Lively sailboat (plans for sail from Wooden Boat Magazine). I suspect
that having volume in the bow may have something to do with it. The
boat has a narrow beam and a very fine bow entry (sorry I haven't any
pics) so it would certainly push aside any waves, but maybe make it a
wet boat in a chop?? Anyway I reckon if you wanted to experiment
cheaply, you could use the bare hull as a basic starting point (four
sheets of ply) and tinker from there,
Cheers,
John
--- Inbolger@yahoogroups.com, "graeme19121984" <graeme19121984@...>
wrote:
>
> John,
>
> you're so lucky to have a library with Bolger books!
>
> CWS is a long time favourite of mine. It's meant to get up and go,
> fast and flat, and I think it would :)
>
> I've never heard of another being built, apart from that one in
> Folding Schooner. I think that might be because the boat is really
> too narrow in application - it can almost be _satisfactorily_ adapted
> to cruising, but it just falls short IMHO, and becomes too difficult
> and fiddly, and there are other boats of that size that are better at
> the job.
>
> You'd want the boat as light as possible for fun speed sailing, so to
> dry store cruising stuff you could have removable boxes fore and aft.
> The forward one can't store much nor take much weight, the aft one
> interferes with the sweep.
>
> Getting rid of the sweep may not be so bad as Bolger wrote later
> about the 12ft carved foam boat, BOXER, in Different Boats, that it
> didn't steer the boat worth a hoot and gave the owner a sore wrist
> every time he went out - he went on to muse that it must be possible
> to make a sweep that can be controled with one hand...
>
> The rig is far from optimal for cruising...
>
> What method for auxilliary power? Where do you sit to row it? Do you
> move the aft storage forward to the mast, and sit with your feet in
> the stern well? The boat is still likely to be bow high and dragging
> the transom, and the sides are not an optimal height for the
> rollicks. The rollicks could have an extended shank to raise them to
> a suitable height. Or do what PCB considered, and rejected then (and
> likewise for June Bug) on aesthetic grounds, but later did on other
> boats by disguising it cunningly with moldings and colour contrast,
> and leave out the sheer by just extending the topsides lines out to
> the straight edge of the plywood on the ply cutting plan. The extra
> free board would provide more welcome shelter when cruising too.
>
> I think CWS would benefit from the lightest materials, a rudder, and
> the sail can be made with some allowance for shortening; and for
> cruising - the most minimal - just a small dry bag of essentials, and
> a paddle to get into a creek.
>
> For mostly cruising though, I have to say that JINNY is about the
> same size, uses the same amount of materials, and is optomised for...
>
> ...But then, the JINNY bottom will never resound with that glorius
> hum, and you, barefoot, will never feel the tingling buzz that a
> light plywood boat rewards her crew with when she hits the plane...
> and the smile grows a mile wide.
>
> (A few years ago now, a couple of guys coastal cruised from Florida
> to New York on board-boat Sunfish look-a-likes.)
>
> Graeme
>
>
> --- Inbolger@yahoogroups.com, "mannthree" <johnmann@> wrote:
> >
> > Greetings,
> >
> > I was at the library reading Bolger Books (Small Boats and The
> Folding
> > Schooner etc) when I came across this design. I find the hull shape
> > rather pleasing to my eye and Bolger has designed the "cockpit in
> such
> > a way that it could be adapted to other uses (eg Camp Cruising).
> She
> > is powered by a Spritsail and steered with a steering sweep. Does
> > anyone have any info/pics or comments on this design. Thanks in
> advance,
> >
> > Regards,
> >
> > John
> >
>
John,
you're so lucky to have a library with Bolger books!
CWS is a long time favourite of mine. It's meant to get up and go,
fast and flat, and I think it would :)
I've never heard of another being built, apart from that one in
Folding Schooner. I think that might be because the boat is really
too narrow in application - it can almost be _satisfactorily_ adapted
to cruising, but it just falls short IMHO, and becomes too difficult
and fiddly, and there are other boats of that size that are better at
the job.
You'd want the boat as light as possible for fun speed sailing, so to
dry store cruising stuff you could have removable boxes fore and aft.
The forward one can't store much nor take much weight, the aft one
interferes with the sweep.
Getting rid of the sweep may not be so bad as Bolger wrote later
about the 12ft carved foam boat, BOXER, in Different Boats, that it
didn't steer the boat worth a hoot and gave the owner a sore wrist
every time he went out - he went on to muse that it must be possible
to make a sweep that can be controled with one hand...
The rig is far from optimal for cruising...
What method for auxilliary power? Where do you sit to row it? Do you
move the aft storage forward to the mast, and sit with your feet in
the stern well? The boat is still likely to be bow high and dragging
the transom, and the sides are not an optimal height for the
rollicks. The rollicks could have an extended shank to raise them to
a suitable height. Or do what PCB considered, and rejected then (and
likewise for June Bug) on aesthetic grounds, but later did on other
boats by disguising it cunningly with moldings and colour contrast,
and leave out the sheer by just extending the topsides lines out to
the straight edge of the plywood on the ply cutting plan. The extra
free board would provide more welcome shelter when cruising too.
I think CWS would benefit from the lightest materials, a rudder, and
the sail can be made with some allowance for shortening; and for
cruising - the most minimal - just a small dry bag of essentials, and
a paddle to get into a creek.
For mostly cruising though, I have to say that JINNY is about the
same size, uses the same amount of materials, and is optomised for...
...But then, the JINNY bottom will never resound with that glorius
hum, and you, barefoot, will never feel the tingling buzz that a
light plywood boat rewards her crew with when she hits the plane...
and the smile grows a mile wide.
(A few years ago now, a couple of guys coastal cruised from Florida
to New York on board-boat Sunfish look-a-likes.)
Graeme
you're so lucky to have a library with Bolger books!
CWS is a long time favourite of mine. It's meant to get up and go,
fast and flat, and I think it would :)
I've never heard of another being built, apart from that one in
Folding Schooner. I think that might be because the boat is really
too narrow in application - it can almost be _satisfactorily_ adapted
to cruising, but it just falls short IMHO, and becomes too difficult
and fiddly, and there are other boats of that size that are better at
the job.
You'd want the boat as light as possible for fun speed sailing, so to
dry store cruising stuff you could have removable boxes fore and aft.
The forward one can't store much nor take much weight, the aft one
interferes with the sweep.
Getting rid of the sweep may not be so bad as Bolger wrote later
about the 12ft carved foam boat, BOXER, in Different Boats, that it
didn't steer the boat worth a hoot and gave the owner a sore wrist
every time he went out - he went on to muse that it must be possible
to make a sweep that can be controled with one hand...
The rig is far from optimal for cruising...
What method for auxilliary power? Where do you sit to row it? Do you
move the aft storage forward to the mast, and sit with your feet in
the stern well? The boat is still likely to be bow high and dragging
the transom, and the sides are not an optimal height for the
rollicks. The rollicks could have an extended shank to raise them to
a suitable height. Or do what PCB considered, and rejected then (and
likewise for June Bug) on aesthetic grounds, but later did on other
boats by disguising it cunningly with moldings and colour contrast,
and leave out the sheer by just extending the topsides lines out to
the straight edge of the plywood on the ply cutting plan. The extra
free board would provide more welcome shelter when cruising too.
I think CWS would benefit from the lightest materials, a rudder, and
the sail can be made with some allowance for shortening; and for
cruising - the most minimal - just a small dry bag of essentials, and
a paddle to get into a creek.
For mostly cruising though, I have to say that JINNY is about the
same size, uses the same amount of materials, and is optomised for...
...But then, the JINNY bottom will never resound with that glorius
hum, and you, barefoot, will never feel the tingling buzz that a
light plywood boat rewards her crew with when she hits the plane...
and the smile grows a mile wide.
(A few years ago now, a couple of guys coastal cruised from Florida
to New York on board-boat Sunfish look-a-likes.)
Graeme
--- Inbolger@yahoogroups.com, "mannthree" <johnmann@...> wrote:
>
> Greetings,
>
> I was at the library reading Bolger Books (Small Boats and The
Folding
> Schooner etc) when I came across this design. I find the hull shape
> rather pleasing to my eye and Bolger has designed the "cockpit in
such
> a way that it could be adapted to other uses (eg Camp Cruising).
She
> is powered by a Spritsail and steered with a steering sweep. Does
> anyone have any info/pics or comments on this design. Thanks in
advance,
>
> Regards,
>
> John
>
Well,
a simple rudder is probably more practical than a steering oar.
"Junebug" is very similiar, probably easier to build, and is an
excellent Bolger design.
But if you like it, you like it.
a simple rudder is probably more practical than a steering oar.
"Junebug" is very similiar, probably easier to build, and is an
excellent Bolger design.
But if you like it, you like it.
On Jan 19, 2008, at 2:06 AM, mannthree wrote:
> Greetings,
>
> I was at the library reading Bolger Books (Small Boats and The Folding
> Schooner etc) when I came across this design. I find the hull shape
> rather pleasing to my eye and Bolger has designed the "cockpit in such
> a way that it could be adapted to other uses (eg Camp Cruising). She
> is powered by a Spritsail and steered with a steering sweep. Does
> anyone have any info/pics or comments on this design. Thanks in
> advance,
>
> Regards,
>
> John
>
>
>
=== craig o'donnell
dadadata@...
Box 232 Betterton Md 21610
[Non-text portions of this message have been removed]
Greetings,
I was at the library reading Bolger Books (Small Boats and The Folding
Schooner etc) when I came across this design. I find the hull shape
rather pleasing to my eye and Bolger has designed the "cockpit in such
a way that it could be adapted to other uses (eg Camp Cruising). She
is powered by a Spritsail and steered with a steering sweep. Does
anyone have any info/pics or comments on this design. Thanks in advance,
Regards,
John
I was at the library reading Bolger Books (Small Boats and The Folding
Schooner etc) when I came across this design. I find the hull shape
rather pleasing to my eye and Bolger has designed the "cockpit in such
a way that it could be adapted to other uses (eg Camp Cruising). She
is powered by a Spritsail and steered with a steering sweep. Does
anyone have any info/pics or comments on this design. Thanks in advance,
Regards,
John