Re: [bolger] Re: Yuloh for Micro.
Don't make it complicated! The idea is to throw water aft. If the blade is
at right angles to the boat's axis, a downward pull on the loom will do it.
If the blade is at an angle, you're emulating part of a propeller and
"screwing" thru the water. A bent loom allows it to be longer without
needing a stepladder.
The "magic" in the yuloh is that the "yankline" gives a downward pull while
reversing the pitch for the return stroke.
Take a regular oar to the stern of a dinghy, with or without notch and
experiment. There's many different strokes which all boil down to the same
idea. Some are more effective and come with practice. Some take strong
wrists.
Don't get caught wiggling the rudder during a Sunfish race. It's illegal,
but it works like an inefficient yuloh and helps in light air conditions.
Roger
derbyrm@...
http://derbyrm.mystarband.net
at right angles to the boat's axis, a downward pull on the loom will do it.
If the blade is at an angle, you're emulating part of a propeller and
"screwing" thru the water. A bent loom allows it to be longer without
needing a stepladder.
The "magic" in the yuloh is that the "yankline" gives a downward pull while
reversing the pitch for the return stroke.
Take a regular oar to the stern of a dinghy, with or without notch and
experiment. There's many different strokes which all boil down to the same
idea. Some are more effective and come with practice. Some take strong
wrists.
Don't get caught wiggling the rudder during a Sunfish race. It's illegal,
but it works like an inefficient yuloh and helps in light air conditions.
Roger
derbyrm@...
http://derbyrm.mystarband.net
----- Original Message -----
From: "Bruce Hallman" <bruce@...>
> I admit that I am having trouble
> comprehending how a Yuloh works, but
> key it seems is that on the push stroke
> the blade feathers counterclockwise, and
> that imparts forward push on the boat.
> On the pull stroke, the Yoloh oar rotates
> clockwise, "like a falling leaf" and imparts
> forward push on the boat.
--- craig o'donnell wrote:
I hadn't see that link, in the
diagram you can see that the rope
on the loom also helps with the
'balance' of the yuloh oar.
> See these if you haven't already:http://www2.cc22.ne.jp/~ozwrow/ozr/waterdev/ro/roe.html
I hadn't see that link, in the
diagram you can see that the rope
on the loom also helps with the
'balance' of the yuloh oar.
See these if you haven't already:
http://freepages.genealogy.rootsweb.com/~fassitt/cranks/mar-mus_sampan.html
http://freepages.genealogy.rootsweb.com/~fassitt/cranks/cranky_sampans.html
Japanese Ro
http://www2.cc22.ne.jp/~ozwrow/ozr/waterdev/ro/roe.html
http://www2.cc22.ne.jp/~ozwrow/ozr/waterdev/ro2/rogalle.html
From David Beede's summary-of-yuloh-stuff page:
http://www.simplicityboats.com/yulohpage.html
--
Craig O'Donnell
Sinepuxent Ancestors & Boats
<http://freepages.genealogy.rootsweb.com/~fassitt/>
The Proa FAQ <http://boat-links.com/proafaq.html>
The Cheap Pages <http://www2.friend.ly.net/~dadadata/>
Sailing Canoes, Polytarp Sails, Bamboo, Chinese Junks,
American Proas, the Bolger Boat Honor Roll,
Plywood Boats, Bamboo Rafts, &c.
_________________________________
-- Professor of Boatology -- Junkomologist
-- Macintosh kinda guy
Friend of Wanda the Wonder Cat, 1991-1997.
_________________________________
---
[This E-mail scanned for viruses by friend.ly.net.]
http://freepages.genealogy.rootsweb.com/~fassitt/cranks/mar-mus_sampan.html
http://freepages.genealogy.rootsweb.com/~fassitt/cranks/cranky_sampans.html
Japanese Ro
http://www2.cc22.ne.jp/~ozwrow/ozr/waterdev/ro/roe.html
http://www2.cc22.ne.jp/~ozwrow/ozr/waterdev/ro2/rogalle.html
From David Beede's summary-of-yuloh-stuff page:
http://www.simplicityboats.com/yulohpage.html
--
Craig O'Donnell
Sinepuxent Ancestors & Boats
<http://freepages.genealogy.rootsweb.com/~fassitt/>
The Proa FAQ <http://boat-links.com/proafaq.html>
The Cheap Pages <http://www2.friend.ly.net/~dadadata/>
Sailing Canoes, Polytarp Sails, Bamboo, Chinese Junks,
American Proas, the Bolger Boat Honor Roll,
Plywood Boats, Bamboo Rafts, &c.
_________________________________
-- Professor of Boatology -- Junkomologist
-- Macintosh kinda guy
Friend of Wanda the Wonder Cat, 1991-1997.
_________________________________
---
[This E-mail scanned for viruses by friend.ly.net.]
>I admit that I am having troubleIt's driving the boat on both sweeps because the oar rotates. The
>comprehending how a Yuloh works, but
>key it seems is that on the push stroke
>the blade feathers counterclockwise, and
>that imparts forward push on the boat.
>On the pull stroke, the Yoloh oar rotates
>clockwise, "like a falling leaf" and imparts
>forward push on the boat.
"leading edge" become the "trailing edge". The key is the yankline,
which generates auto feathering and allows you to push with the upper
body on one stroke and then "fall away" using gravity to help on the
return.
--
Craig O'Donnell
Sinepuxent Ancestors & Boats
<http://freepages.genealogy.rootsweb.com/~fassitt/>
The Proa FAQ <http://boat-links.com/proafaq.html>
The Cheap Pages <http://www2.friend.ly.net/~dadadata/>
Sailing Canoes, Polytarp Sails, Bamboo, Chinese Junks,
American Proas, the Bolger Boat Honor Roll,
Plywood Boats, Bamboo Rafts, &c.
_________________________________
-- Professor of Boatology -- Junkomologist
-- Macintosh kinda guy
Friend of Wanda the Wonder Cat, 1991-1997.
_________________________________
---
[This E-mail scanned for viruses by friend.ly.net.]
-- craig o'donnell wrote:
mechanics, reading the couple of
detailed Yuloh websites found by
Google and the PCB writings in
30-Odd-Boats.
One thing clear, is that PCB's
design of a Yuloh was made folding
for the reason of experimenting with
various pitches of the blade. "the bent
oar effect" ...and although it could be
made straight, PCB preferred a bend.
I admit that I am having trouble
comprehending how a Yuloh works, but
key it seems is that on the push stroke
the blade feathers counterclockwise, and
that imparts forward push on the boat.
On the pull stroke, the Yoloh oar rotates
clockwise, "like a falling leaf" and imparts
forward push on the boat.
The yanking rope both helps in the rotation,
and also is helpful in exerting power.
I was sizing up the geometry of the Micro
Navigator Navigator, and find that it fits good
for the use of a Yuloh, with the swing of the loom
and the swing of the blade fitting well through
the door of the cabin and the cutout for the motor.
> Yulohs can be straight.I am trying to figure out the
> The key is the "yankline"
mechanics, reading the couple of
detailed Yuloh websites found by
Google and the PCB writings in
30-Odd-Boats.
One thing clear, is that PCB's
design of a Yuloh was made folding
for the reason of experimenting with
various pitches of the blade. "the bent
oar effect" ...and although it could be
made straight, PCB preferred a bend.
I admit that I am having trouble
comprehending how a Yuloh works, but
key it seems is that on the push stroke
the blade feathers counterclockwise, and
that imparts forward push on the boat.
On the pull stroke, the Yoloh oar rotates
clockwise, "like a falling leaf" and imparts
forward push on the boat.
The yanking rope both helps in the rotation,
and also is helpful in exerting power.
I was sizing up the geometry of the Micro
Navigator Navigator, and find that it fits good
for the use of a Yuloh, with the swing of the loom
and the swing of the blade fitting well through
the door of the cabin and the cutout for the motor.
>I know it's him youno, a couple years back he was definitely using a yuloh. Yulohs can
>are talking about, but I guess the bamboo shaft of his oar fooled us. Here's
>a poor picture of Mark at work with the oar:
be straight. The key is the "yankline" - to coin a term - from loom
to deck.
--
Craig O'Donnell
Sinepuxent Ancestors & Boats
<http://freepages.genealogy.rootsweb.com/~fassitt/>
The Proa FAQ <http://boat-links.com/proafaq.html>
The Cheap Pages <http://www2.friend.ly.net/~dadadata/>
Sailing Canoes, Polytarp Sails, Bamboo, Chinese Junks,
American Proas, the Bolger Boat Honor Roll,
Plywood Boats, Bamboo Rafts, &c.
_________________________________
-- Professor of Boatology -- Junkomologist
-- Macintosh kinda guy
Friend of Wanda the Wonder Cat, 1991-1997.
_________________________________
---
[This E-mail scanned for viruses by friend.ly.net.]
Looking at my photos from this year's PT festival, I see that Mark (the
"Outdoorsman") was using a straight-loomed sculling oar. I know it's him you
are talking about, but I guess the bamboo shaft of his oar fooled us. Here's
a poor picture of Mark at work with the oar:
http://groups.yahoo.com/group/Bolger2/files/Sculler.jpg
I really ought to take some close-up shots of the setup one of these years...
"Outdoorsman") was using a straight-loomed sculling oar. I know it's him you
are talking about, but I guess the bamboo shaft of his oar fooled us. Here's
a poor picture of Mark at work with the oar:
http://groups.yahoo.com/group/Bolger2/files/Sculler.jpg
I really ought to take some close-up shots of the setup one of these years...
On Tue, 7 Oct 2003 11:01:33 -0400, COD wrote:
> ...
> I've seen one in use (Port Townsend WB Fest) but the guy, a true
> Outdoorsman type, did not deign to talk to me. Probably because I was in
> one of those girly-boats, a lapstrake canoe.
> ...
--
John <jkohnen@...>
http://www.boat-links.com/
Show me a man who has enjoyed his school days and I'll show you a
bully and a bore. <Robert Morley>
That'd be Mark. Mark's alright, but he doesn't suffer fools gladly. ;o) I'd
talked to him a bit at the launch ramp in the boat basin at the ends of
different PT festivals, and he was a bit standoffish at first, worried, I
suppose, that I was another of those "girly boat" types, or worse, a mere
gawker with no boat at all! But by this year I guess he'd decided I was
alright myself, because after I waved at him as he was sculling into the
boat basin he came over and had a beer with us in the cockpit of Jamie's
Chebacco. He took to the Canadians and went off with them to the brew-pub in
the middle of the boatyard area while I went sailing.
Maybe next year we can get him to talk about his yuloh. <g>
talked to him a bit at the launch ramp in the boat basin at the ends of
different PT festivals, and he was a bit standoffish at first, worried, I
suppose, that I was another of those "girly boat" types, or worse, a mere
gawker with no boat at all! But by this year I guess he'd decided I was
alright myself, because after I waved at him as he was sculling into the
boat basin he came over and had a beer with us in the cockpit of Jamie's
Chebacco. He took to the Canadians and went off with them to the brew-pub in
the middle of the boatyard area while I went sailing.
Maybe next year we can get him to talk about his yuloh. <g>
On Tue, 7 Oct 2003 11:01:33 -0400, COD wrote:
> ...
> I've seen one in
> use (Port Townsend WB Fest) but the guy, a true Outdoorsman type, did
> not deign to talk to me. Probably because I was in one of those
> girly-boats, a lapstrake canoe.
--
John <jkohnen@...>
http://www.boat-links.com/
I Can't take a well-tanned person seriously. <Cleveland Amory>
Responding to several message on this thread
including:
--- Sam Glasscocks:
dimensioned and detailed] of his take on a Yuloh, with
a couple pages of text describing his 'sea trials'
[including ideas of how to improve his design {bigger
blade}] and a photo of him using it.
I imagine that with wind available, I will sail,
and the Yuloh will be used mostly when there is no
wind.
The Yuloh is an ancient invention, and most things
that have stood the test of time work well, sometimes
better [and always simpler] than new fangled things.
Quoting: "
Swallow�s Yuloh
Swallow is a suitable boat for yuloh propulsion, light
but with a long keel to keep the tail from wagging the
dog. Her short length made the folding feature
appropriate, though it was mainly a by-product of my
wanting to try an adjustable-pitch blade. The angle of
the knuckle between the blade and loom of a yuloh
controls the pitch of its blade in action. In this
version it can be altered by changing the length of
the lanyard from the heel of the loom through the slot
in the blade.
Larry Dahlmer made the thing accurately, but the man
who fur- nished the metalwork came up with a universal
joint of his own devising, [looks like a trailer
hitch, Bruce] so I didn�t get a test of how well the
designed open rest would have worked. The joint
supplied had the annoying drawback that it couldn�t
suddenly be taken away to unclutter the stern for
sailing. The corresponding advantage was that it
wouldn�t hop off at the wrong time. It happened to
have a limited travel that made the usual lanyard on
the loom unnecessary. I�d meant to try taking this to
a point farther forward on deck than the straight-down
angle of the classic Chinese yuloh, but, as the photo
shows, it would work without any lanyard control at
all.~ This gadget drove Swallow with very little
effort, but not nearly as fast as I�d hoped. I think I
could scull her faster with a straight- bladed oar, or
paddle her as fast, though I�d probably wear out
sooner with either than I did with the yuloh. I�m
going to try it with a longer blade when I get around
to it. The leverage feels to me as though it could
stand a foot- or foot-and-a-half-deeper blade,
especially with the option of reducing the pitch. The
pitch shown in the photo was all it would take without
stalling the blade on a hard stroke.
including:
--- Sam Glasscocks:
> Does Bolgers article in 30-Odd Boats have suchYes, is includes one of his 'design' drawings [fully
> details?
dimensioned and detailed] of his take on a Yuloh, with
a couple pages of text describing his 'sea trials'
[including ideas of how to improve his design {bigger
blade}] and a photo of him using it.
I imagine that with wind available, I will sail,
and the Yuloh will be used mostly when there is no
wind.
The Yuloh is an ancient invention, and most things
that have stood the test of time work well, sometimes
better [and always simpler] than new fangled things.
Quoting: "
Swallow�s Yuloh
Swallow is a suitable boat for yuloh propulsion, light
but with a long keel to keep the tail from wagging the
dog. Her short length made the folding feature
appropriate, though it was mainly a by-product of my
wanting to try an adjustable-pitch blade. The angle of
the knuckle between the blade and loom of a yuloh
controls the pitch of its blade in action. In this
version it can be altered by changing the length of
the lanyard from the heel of the loom through the slot
in the blade.
Larry Dahlmer made the thing accurately, but the man
who fur- nished the metalwork came up with a universal
joint of his own devising, [looks like a trailer
hitch, Bruce] so I didn�t get a test of how well the
designed open rest would have worked. The joint
supplied had the annoying drawback that it couldn�t
suddenly be taken away to unclutter the stern for
sailing. The corresponding advantage was that it
wouldn�t hop off at the wrong time. It happened to
have a limited travel that made the usual lanyard on
the loom unnecessary. I�d meant to try taking this to
a point farther forward on deck than the straight-down
angle of the classic Chinese yuloh, but, as the photo
shows, it would work without any lanyard control at
all.~ This gadget drove Swallow with very little
effort, but not nearly as fast as I�d hoped. I think I
could scull her faster with a straight- bladed oar, or
paddle her as fast, though I�d probably wear out
sooner with either than I did with the yuloh. I�m
going to try it with a longer blade when I get around
to it. The leverage feels to me as though it could
stand a foot- or foot-and-a-half-deeper blade,
especially with the option of reducing the pitch. The
pitch shown in the photo was all it would take without
stalling the blade on a hard stroke.
>Does anyone know a source for plans, constuctionThere are several yuloh pages on the web that go into some detail. I
>details, how to size the loom, etc. for the yuloh?
>Does Bolgers article in 30-odd boats have such
>details? I'd love to replace the sweeps on my Topaz
>with a yuloh, but have only the most rudimentary idea
>of how they work. Thanks for the help. Sam
think I have a lot of info somewhere <chuckle> that got compiled when
I realized that the question of yulohs always comes up and the info
never seemed to be collected in one place... on some page or other.
Search the Cheap Pages for the link. There's also a Japanese site
that looks pretty informative but the images are so low res that it's
hard to get any dimensions off the drawings and the owner said he
would, but never did, supply me with higher-res scans.
A trailer ball is probably the best mount. Somewhere I have Bill
(rip) Foden's illustrated article on his shantyboat yuloh though most
of the material deals with a clamp-on universal fulcrum. It might
take me months to find the article unless I have it scanned
somewhere....
The idea seems to be to get the blade into the water at perhaps a 20
degree angle; crooks in the loom bring the handle to breast-high
govern your individual boat and how tall you are. A line to a ring
from the handle is all that's otherwise required. I've seen one in
use (Port Townsend WB Fest) but the guy, a true Outdoorsman type, did
not deign to talk to me. Probably because I was in one of those
girly-boats, a lapstrake canoe.
--
Craig O'Donnell
Sinepuxent Ancestors & Boats
<http://freepages.genealogy.rootsweb.com/~fassitt/>
The Proa FAQ <http://boat-links.com/proafaq.html>
The Cheap Pages <http://www2.friend.ly.net/~dadadata/>
Sailing Canoes, Polytarp Sails, Bamboo, Chinese Junks,
American Proas, the Bolger Boat Honor Roll,
Plywood Boats, Bamboo Rafts, &c.
_________________________________
-- Professor of Boatology -- Junkomologist
-- Macintosh kinda guy
Friend of Wanda the Wonder Cat, 1991-1997.
_________________________________
---
[This E-mail scanned for viruses by friend.ly.net.]
Does anyone know a source for plans, constuction
details, how to size the loom, etc. for the yuloh?
Does Bolgers article in 30-odd boats have such
details? I'd love to replace the sweeps on my Topaz
with a yuloh, but have only the most rudimentary idea
of how they work. Thanks for the help. Sam
--- proaconstrictor <proaconstrictor@...> wrote:
Do you Yahoo!?
The New Yahoo! Shopping - with improved product search
http://shopping.yahoo.com
details, how to size the loom, etc. for the yuloh?
Does Bolgers article in 30-odd boats have such
details? I'd love to replace the sweeps on my Topaz
with a yuloh, but have only the most rudimentary idea
of how they work. Thanks for the help. Sam
--- proaconstrictor <proaconstrictor@...> wrote:
>__________________________________
> Yullohs are great, that little one he designed seems
> almost just an
> extention of working the rudder. I feel the bigger
> the better,
> within reason. It's hard to believe the folding is
> unique, since
> that dogleg style is very old, and someone must have
> considered it
> for storage.
>
Do you Yahoo!?
The New Yahoo! Shopping - with improved product search
http://shopping.yahoo.com
>You probably have seen this link, though maybe others haven't. A lotDoesn't David have a different site now?
>of the photos don't seem to pop anymore... :
>
>http://members.tripod.com/simplicityboats/yulohpage.html
--
Craig O'Donnell
Sinepuxent Ancestors & Boats
<http://freepages.genealogy.rootsweb.com/~fassitt/>
The Proa FAQ <http://boat-links.com/proafaq.html>
The Cheap Pages <http://www2.friend.ly.net/~dadadata/>
Sailing Canoes, Polytarp Sails, Bamboo, Chinese Junks,
American Proas, the Bolger Boat Honor Roll,
Plywood Boats, Bamboo Rafts, &c.
_________________________________
-- Professor of Boatology -- Junkomologist
-- Macintosh kinda guy
Friend of Wanda the Wonder Cat, 1991-1997.
_________________________________
---
[This E-mail scanned for viruses by friend.ly.net.]
>Yullohs are great, that little one he designed seems almost just an
> The 'fin' keel [and tied down rudder]
> of Micro would work with a Yuloh, I guess.
extention of working the rudder. I feel the bigger the better,
within reason. It's hard to believe the folding is unique, since
that dogleg style is very old, and someone must have considered it
for storage.
His hinge and a Kayak joint would give you a pretty nice little stick
I know one guy who sailed all over the east coast in a 24 foot tri
using nothing but a Yulloh as auxiliary, He mounted a trailer hitch
on the transom and dug out a socket in his sweep.
You probably have seen this link, though maybe others haven't. A lot
of the photos don't seem to pop anymore... :
http://members.tripod.com/simplicityboats/yulohpage.html
--- Inbolger@yahoogroups.com, Bruce Hallman <bruce@h...> wrote:
wants a new design that looks like a SNEAKEASY as a warm up to the
real thing and because his garage is too small.Will it get bigger
after the"warm up" session when it is time to build SNEAKEASY?
I say,pass on the "warm-up",take whatever money was budgeted for the
shorter boat and build/add an extension to the garage and procceed
with SNEAKEASY..........she's not all that difficult a boat to build
and you will soon have exactly the boat you wanted in the first
place:-)
Besides,there are a few SNEAKEASY owner/builders right here in the
group that will surely help the chap along if things aren't clear.
Sincerely,
Peter "love to hear about boatbuilding" Lenihan
>I wouldn't mess with success either Bruce.......the fellow clearly
> I have built several of PCB's designs, and
> literally *every* time, I have come to
> realize that revisions to his design have
> unintended consequences!
wants a new design that looks like a SNEAKEASY as a warm up to the
real thing and because his garage is too small.Will it get bigger
after the"warm up" session when it is time to build SNEAKEASY?
I say,pass on the "warm-up",take whatever money was budgeted for the
shorter boat and build/add an extension to the garage and procceed
with SNEAKEASY..........she's not all that difficult a boat to build
and you will soon have exactly the boat you wanted in the first
place:-)
Besides,there are a few SNEAKEASY owner/builders right here in the
group that will surely help the chap along if things aren't clear.
Sincerely,
Peter "love to hear about boatbuilding" Lenihan
Has anybody else given thought to
the chapter in 30-Odd-Boats about
the PCB designed Yuloh for Swallow?
[page 189]
A folding Yuloh is a unique PCB
idea, is it not? It would fit nicely
on the cabin roof.
The 'fin' keel [and tied down rudder]
of Micro would work with a Yuloh, I guess.
I hate the idea of paying more for
an outboard motor than I paid for
my entire boat. All I need is power in
the marina, I figure.
Not to mention that the State licensing
fees are less for boats without engines.
I think that the geometry of the
Yuloh for Swallow could work with
a Micro, upsized a bit, or at least
it is worth a try.
the chapter in 30-Odd-Boats about
the PCB designed Yuloh for Swallow?
[page 189]
A folding Yuloh is a unique PCB
idea, is it not? It would fit nicely
on the cabin roof.
The 'fin' keel [and tied down rudder]
of Micro would work with a Yuloh, I guess.
I hate the idea of paying more for
an outboard motor than I paid for
my entire boat. All I need is power in
the marina, I figure.
Not to mention that the State licensing
fees are less for boats without engines.
I think that the geometry of the
Yuloh for Swallow could work with
a Micro, upsized a bit, or at least
it is worth a try.
So you're saying that rudder placement isn't going to be an issue here?
;-)
David Romasco
-----Original Message-----
From: pvanderwaart [mailto:pvanderw@...]
Sent: Monday, October 06, 2003 2:50 PM
To:bolger@yahoogroups.com
Subject: [bolger] Re: when scaling down or up sneakeasy
sails/centerboard/Sneakeasy
Uumm, am I confused or does this trio not actually belong together.
The consensus is that any change greater than a 10% scaling
constitutes a new design, and requires new engineering from scratch.
Such warning should be taken especially seriously in the case of
Sneakeasy since it is a somewhat dangerous design in the first place.
The danger is that she is a low power/moderate speed boat that looks
like a high speed boat. Pushed to water skiing speeds, she could be
on the edge of trouble in an instant. So says Bolger.
I thought the suggestions about alternate Bolger designs in the
desired size range were excellent.
Peter
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- stay on topic, stay on thread, punctuate, no 'Ed, thanks, Fred' posts
- Pls add your comments at the TOP, SIGN your posts, and snip away
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;-)
David Romasco
-----Original Message-----
From: pvanderwaart [mailto:pvanderw@...]
Sent: Monday, October 06, 2003 2:50 PM
To:bolger@yahoogroups.com
Subject: [bolger] Re: when scaling down or up sneakeasy
sails/centerboard/Sneakeasy
Uumm, am I confused or does this trio not actually belong together.
The consensus is that any change greater than a 10% scaling
constitutes a new design, and requires new engineering from scratch.
Such warning should be taken especially seriously in the case of
Sneakeasy since it is a somewhat dangerous design in the first place.
The danger is that she is a low power/moderate speed boat that looks
like a high speed boat. Pushed to water skiing speeds, she could be
on the edge of trouble in an instant. So says Bolger.
I thought the suggestions about alternate Bolger designs in the
desired size range were excellent.
Peter
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sails/centerboard/Sneakeasy
Uumm, am I confused or does this trio not actually belong together.
The consensus is that any change greater than a 10% scaling
constitutes a new design, and requires new engineering from scratch.
Such warning should be taken especially seriously in the case of
Sneakeasy since it is a somewhat dangerous design in the first place.
The danger is that she is a low power/moderate speed boat that looks
like a high speed boat. Pushed to water skiing speeds, she could be
on the edge of trouble in an instant. So says Bolger.
I thought the suggestions about alternate Bolger designs in the
desired size range were excellent.
Peter
Uumm, am I confused or does this trio not actually belong together.
The consensus is that any change greater than a 10% scaling
constitutes a new design, and requires new engineering from scratch.
Such warning should be taken especially seriously in the case of
Sneakeasy since it is a somewhat dangerous design in the first place.
The danger is that she is a low power/moderate speed boat that looks
like a high speed boat. Pushed to water skiing speeds, she could be
on the edge of trouble in an instant. So says Bolger.
I thought the suggestions about alternate Bolger designs in the
desired size range were excellent.
Peter
--- Mi'ki <mike78612003@...> wrote:
literally *every* time, I have come to
realize that revisions to his design have
unintended consequences! Mr. Bolger has
spent a lifetime learning 'why' boats need
to be this way and that. He may be the most
learned boat historian/designer alive [at least
he is in the top echelon].
I forget where PCB wrote; I'll paraphrase, that
he has no intention of becoming another boat
designer to die in a boat of his or her own design.
A powerboat like Sneakeasy, capable of high
speeds should be modified [and operated] carefully
because it could be dangerous.
Never-the-less, if you want to learn about
how to design boats, and to modify designs of
boats, studying Phil Bolger's work is a good place
to start.
You might also check out the boat designs of
Jim Michalak, who is a PCB fan, and who has
spent much time thinking and writing about
boat designs. I recall reading an excellent
article by him that explains about the center
of the sails relative to the center of lateral
resistance.
> where do you draw the center of enough in the sailsI have built several of PCB's designs, and
> in relationship to the center board being up or
> down, because as the boat gets bigger or smaller
> does the weight ration change how much did you
> reduce the sneakeasy
literally *every* time, I have come to
realize that revisions to his design have
unintended consequences! Mr. Bolger has
spent a lifetime learning 'why' boats need
to be this way and that. He may be the most
learned boat historian/designer alive [at least
he is in the top echelon].
I forget where PCB wrote; I'll paraphrase, that
he has no intention of becoming another boat
designer to die in a boat of his or her own design.
A powerboat like Sneakeasy, capable of high
speeds should be modified [and operated] carefully
because it could be dangerous.
Never-the-less, if you want to learn about
how to design boats, and to modify designs of
boats, studying Phil Bolger's work is a good place
to start.
You might also check out the boat designs of
Jim Michalak, who is a PCB fan, and who has
spent much time thinking and writing about
boat designs. I recall reading an excellent
article by him that explains about the center
of the sails relative to the center of lateral
resistance.
where do you draw the center of enough in the sails in relationship to the center board being up or down, because as the boat gets bigger or smaller does the weight ration change how much did you reduce the sneakeasy
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