Subject: [harryproa] Re: Current rudder design?
From: "tsstproa" <bitme1234@yahoo.com>
Date: 5/30/2008, 9:59 AM
To: harryproa@yahoogroups.com.au
Reply-to:
harryproa@yahoogroups.com.au

Its just finding the correct geomtry to allow specific sail being
used to feather through Aframe if back winded.

I see where you would think having two sails would make it easier to
set for any condition in deep water.

But what could be easier than one line to reef sail and another to
shift entire sail from fore to aft. Instead of worring about two
sets of everything.

Todd

--- In harryproa@yahoogroups.com.au, "Robert" <cateran1949@...>
wrote:
>
> If the sails were as easy to shunt and good in being caught aback,
I
> would be with you all the way. I intend to set up a system similar
to
> your A frame on my 5m outrigger proa using a windsurfer rig. It is
> designed for paddling out to snorkeling and fishing spots, and it
> would be nice to sail home when the wind gets up.
>
> When you are in deeper water with a schooner rig, you power up. You
> are not feathering all the time
> Robert--- In harryproa@yahoogroups.com.au, "tsstproa" <bitme1234@>
> wrote:
> >
> > I don't know less depth less likely to hit somthing. Sounds good
for
> > cruising or racing. Also smaller boards possibly working under
less
> > strain on structure.
> >
> > Also one sail less gear along with shorter board depths = less
drag
> > What a waste to have one sail feathering in the wake of another.
> >
> > Better balance faster foward speeds with least amount of forces
all
> > around.
> >
> > Todd
> >
> > --- In harryproa@yahoogroups.com.au, "Robert" <cateran1949@>
> > wrote:
> > >
> > Whether to
> > > have the hassle of a large rudder or the hassle of moving the
sail.
> > > For skinny water, but for deeper water, I would
> > > prefer the deeper foils.
> > > I feel the two masted set up can achieve both, though not as
> > > elegantly as Todd's system, as the forward sail is about 1/3
back
> > and
> > > you can leave the aft sail feathered: simply not driving it as
> > hard in
> > > skinny water.
> > > I think for Doug's boat, if the ww hull is a little heavy for
the
> > > system, you could narrow the beam or put some of the gear in
the lw
> > > hull. I'd make sure the foils were near perfect first. If
there are
> > > significant imperfections, the foils will stall too easily.
Maybe
> > put
> > > those lumps on the leading edge, as found on humpback whales,
which
> > > prevent stalling.
> > > Robert
> > >
> > > -- In harryproa@yahoogroups.com.au, "tsstproa" <bitme1234@>
wrote:
> > > >
> > > > Hey Doug ,
> > > >
> > > > In reference to sail/sails. If you could get any single sail
> > with in
> > > > reasonable size for your boats length and weight with its
> > leading
> > > > edge at about 1/4-1/3 the way back from foward bow, and
trailing
> > > > edge of sail no further back than 5/8-3/4 from foward bow
on
> > > > leeward hull. Your boat would have amazing handling and with
the
> > > > lightest helm you could have ever imagined. With less hassle
of
> > the
> > > > two sails. I'll steak all the boats in my back yard and all
my
> > > > models. I Would have said reputation but whats that but pop
> > culture
> > > > None valued to me. If I'm wrong come tak'em all, there
yours!
> > This
> > > > will allow the use of your current boards as is instead of
> > needing
> > > > to place them closer to the bows.
> > > >
> > > > Here are my two solution in getting sail area to the correct
> > > > location for both tacks for both bows. One evolved from the
> > other.
> > > > One balances traditional the other modern.
> > > >
> > > > http://www.youtube.com/watch?v=_PaWgwc4HwI
> > > > http://www.youtube.com/watch?v=jo6QCBjb4rk
> > > > http://www.youtube.com/watch?v=Mt-QZzlY0lM&feature=related
> > > >
> > > > Todd
> > > >
> > > > --- In harryproa@yahoogroups.com.au, Doug Haines <doha720@>
> > wrote:
> > > > >
> > > > > I do feel the effect of letting the rear sail off a bit to
> > help
> > > > when the wind is light&nbsp; or somethign ==.
> > > > > drag was the main issue though for the brackets not going
near
> > the
> > > > water. Not just out of the water but a long way up high to
be
> > sure
> > > > of not catchin gin a big wave washing up along the bow. Just
> > ease of
> > > > mind, to have no possible achillies heels.
> > > > > &nbsp;
> > > > > Doug
> > > > >
> > > > > --- On Wed, 28/5/08, Robert cateran1949@ wrote:
> > > > >
> > > > > From: Robert cateran1949@
> > > > > Subject: [harryproa] Re: Current rudder design?
> > > > > To: harryproa@yahoogroups.com.au
> > > > > Date: Wednesday, 28 May, 2008, 7:30 PM
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > > Hi Doug,
> > > > > I always wondered why you couldn't make the brackets
angled
> > lifting
> > > > > foils, though there is so much reserve righting moment
that I
> > can't
> > > > > imagine I would push it that hard. I would be quite happy
to
> > cruise
> > > > > along at 25 knots ;&gt;)
> > > > > My understanding is that if the rear rudder is holding the
> > boat
> > > > from
> > > > > luffing up but is near the edge, then you can always use a
> > little
> > > > > front rudder to steer- providing it is set up to do so. If
> > this is
> > > > > happening in strong winds and messy seas, then you can
drive
> > the
> > > > > foresail more than the rear one to change the balance. If
> > there are
> > > > > greater difficulties in light winds, then having the
rudder
> > further
> > > > > back won't improve things, but you can load the rear sail
more
> > than
> > > > > the fore or put the front rudder down a little. Having a
> > really
> > > > clean
> > > > > accurate foil can also do wonders.
> > > > > Your boat is relatively heavy on the ww hull and that
could be
> > > > > contributing.
> > > > > Robert--- In harryproa@yahoogrou ps.com.au, Doug Haines
> > doha720@
> > > > &gt;
> > > > > wrote:
> > > > > &gt;
> > > > > &gt; Hi robert,
> > > > > &gt; &amp;nbsp;
> > > > > &gt; I'm imagining how high you need to keep it on a big
boat
> > in a
> > > > big
> > > > > sea. Ijust start to get splashes of spray sometimes now
where
> > the
> > > > beam
> > > > > comes off the side. I haven't been sailing out in the sea
much
> > for
> > > > a
> > > > > long time though. There isn't any slowing for me, but I
> > understand
> > > > the
> > > > > concensus was there was noticeable drag on the old side
mount
> > style
> > > > > eg, elementarry racing etc. It looks like a possible cause
of
> > pitch
> > > > > poling when you start to push the bow down. It makes you
worry
> > > > about
> > > > > attaching rudders higher up. Eg new beam siting. (PS I
still
> > reckon
> > > > > the beams may not be far aft enough to get good response)
> > > > > &gt; &amp;nbsp;
> > > > > &gt; Dopug
> > > > > &gt;
> > > > > &gt; --- On Tue, 27/5/08, Robert cateran1949@ ... wrote:
> > > > > &gt;
> > > > > &gt; From: Robert cateran1949@ ...
> > > > > &gt; Subject: [harryproa] Re: Current rudder design?
> > > > > &gt; To: harryproa@yahoogrou ps.com.au
> > > > > &gt; Date: Tuesday, 27 May, 2008, 8:12 PM
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt; -Hi Doug,
> > > > > &gt; I was wondering if you felt the boat slow down
> > significantly
> > > > at the
> > > > > &gt; moment when the rudder supports went through waves.
> > > > > &gt; I actually did mean to lock off the rear and steer
with
> > the
> > > > front.
> > > > > &gt; Theoretically there would be much less load on the
tiller
> > and
> > > > better
> > > > > &gt; response.
> > > > > &gt; Robert
> > > > > &gt; -- In harryproa@yahoogrou ps.com.au, Doug Haines
doha720@
> > > > &amp;gt; wrote:
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt; Hi Robert,
> > > > > &gt; &amp;gt; &amp;amp;nbsp;
> > > > > &gt; &amp;gt; I think there is a lot of drag on the side
> > mounted
> > > > rudders. I
> > > > > &gt; managed tp keep the connection to hull up fairly high
but
> > > > still could
> > > > > &gt; do with more clearence. It is very unpleasing to see
> > water go
> > > > any
> > > > > &gt; where near the front gear.
> > > > > &gt; &amp;gt; Also I don't know about steering with the
front
> > > > rudder, I think you
> > > > > &gt; meant lock off the front and steer with the backone.
> > > > > &gt; &amp;gt; &amp;amp;nbsp;
> > > > > &gt; &amp;gt; Doug
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt; --- On Mon, 26/5/08, Robert cateran1949@ ...
> > wrote:
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt; From: Robert cateran1949@ ...
> > > > > &gt; &amp;gt; Subject: [harryproa] Re: Current rudder
design?
> > > > > &gt; &amp;gt; To: harryproa@yahoogrou ps.com.au
> > > > > &gt; &amp;gt; Date: Monday, 26 May, 2008, 3:29 PM
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt; -There are various iterations, depending on
> > boat.
> > > > The earlier
> > > > > ones are
> > > > > &gt; &amp;gt; attached to the side of the hulls and work
well
> > but
> > > > add to the
> > > > > &gt; &amp;gt; complexity of the hulls and possibly drag (I
am
> > not
> > > > so sure
> > > > > that they
> > > > > &gt; &amp;gt; add significant drag and would be quite
happy
> > with
> > > > them). These
> > > > > &gt; &amp;gt; rudders had 270 degrees maneuverability.
They
> > can be
> > > > seen quite
> > > > > &gt; &amp;gt; clearly on the harryproa website on 'rare
bird'
> > > > and 'aroha'.
> > > > > Rob has
> > > > > &gt; &amp;gt; been working on beam hung rudders, playing
> > around
> > > > with them on the
> > > > > &gt; &amp;gt; little Elementarry, and you can see how they
> > have
> > > > developed in
> > > > > some of
> > > > > &gt; &amp;gt; the files and photos. They are designed for
360
> > > > degrees. He has
> > > > > done
> > > > > &gt; &amp;gt; some finite analysis engineering to work out
the
> > > > stresses to
> > > > > make sure
> > > > > &gt; &amp;gt; the mounts are strong enough. From what I
can
> > > > gather, the beam hung
> > > > > &gt; &amp;gt; rudders can be lifted for skinny water or
swung
> > out
> > > > of the way.
> > > > > They
> > > > > &gt; &amp;gt; also have means of kicking up either
direction
> > if
> > > > necessary. If the
> > > > > &gt; &amp;gt; motors are placed on the rudders it becomes
more
> > > > difficult to
> > > > > retract
> > > > > &gt; &amp;gt; them for skinny water. The rear rudder is a
> > large
> > > > part of the
> > > > > leeway
> > > > > &gt; &amp;gt; resistance and therefore need they need to
be
> > fairly
> > > > > substantial and
> > > > > &gt; &amp;gt; strong. Some find it useful to lock the rear
> > rudder
> > > > and steer
> > > > > with a
> > > > > &gt; &amp;gt; partially lifted front rudder. For tight
> > maneuvering
> > > > the two
> > > > > rudders
> > > > > &gt; &amp;gt; together allow you to crab or spin in
circles.
> > The
> > > > early
> > > > > rudders had
> > > > > &gt; &amp;gt; the toe leaning forward to allow balance.
This
> > may
> > > > have helped in
> > > > > &gt; &amp;gt; avoiding ventilation.
> > > > > &gt; &amp;gt; Robert - In harryproa@yahoogrou
> > > > ps.com.au, "gardnerpomper"
> > > > > &gt; &amp;gt; gardner@ &amp;amp;gt; wrote:
> > > > > &gt; &amp;gt; &amp;amp;gt;
> > > > > &gt; &amp;gt; &amp;amp;gt; Hi,
> > > > > &gt; &amp;gt; &amp;amp;gt;
> > > > > &gt; &amp;gt; &amp;amp;gt; Is there any information
(sketch or
> > > > drawing,
> > > > > preferably) of the
> > > > > &gt; &amp;gt; &amp;amp;gt; current rudder design? This is
one
> > of
> > > > my areas of
> > > > > concern, and
> > > > > &gt; I would
> > > > > &gt; &amp;gt; &amp;amp;gt; like to see what the current
> > thinking
> > > > is. Specific
> > > > > questions are:
> > > > > &gt; &amp;gt; &amp;amp;gt;
> > > > > &gt; &amp;gt; &amp;amp;gt; what are the dimensions of the
> > rudders?
> > > > > &gt; &amp;gt; &amp;amp;gt;
> > > > > &gt; &amp;gt; &amp;amp;gt; are they designed to lift in
the
> > rudder
> > > > assembly for
> > > > > shoal draft
> > > > > &gt; &amp;gt; &amp;amp;gt; sailing, or do they tilt?
> > > > > &gt; &amp;gt; &amp;amp;gt;
> > > > > &gt; &amp;gt; &amp;amp;gt; Do they need 360 degrees
> > > > maneuverability, or just +/- 45
> > > > > &gt; degrees from
> > > > > &gt; &amp;gt; &amp;amp;gt; the direction of motion? (i.e
335-
> > 45
> > > > degrees, and
> > > > > 135-225 degrees,
> > > > > &gt; &amp;gt; &amp;amp;gt; relative to the hulls)
> > > > > &gt; &amp;gt; &amp;amp;gt;
> > > > > &gt; &amp;gt; &amp;amp;gt; I am specifically speaking of
the
> > > > charter proa, but I
> > > > > am curious if
> > > > > &gt; &amp;gt; &amp;amp;gt; the basic rudder design applies
to
> > > > pretty much any
> > > > > size harryproa.
> > > > > &gt; &amp;gt; &amp;amp;gt;
> > > > > &gt; &amp;gt; &amp;amp;gt; Thanks,
> > > > > &gt; &amp;gt; &amp;amp;gt; - Gardner
> > > > > &gt; &amp;gt; &amp;amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt;
> > > > > &gt; &amp;gt; ____________ _________ _________ _________
> > _________
> > > > _________ _
> > > > > &gt; &amp;gt; Sent from Yahoo! Mail.
> > > > > &gt; &amp;gt; A Smarter Email http://uk.docs. yahoo.com/
> > > > nowyoucan. html
> > > > > &gt; &amp;gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt;
> > > > > &gt; ____________ _________ _________ _________ _________
> > > > _________ _
> > > > > &gt; Sent from Yahoo! Mail.
> > > > > &gt; A Smarter Email http://uk.docs. yahoo.com/ nowyoucan.
html
> > > > > &gt;
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > > > >
> > __________________________________________________________
> > > > > Sent from Yahoo! Mail.
> > > > > A Smarter Email http://uk.docs.yahoo.com/nowyoucan.html
> > > > >
> > > >
> > >
> >
>

__._,_.___
Recent Activity
Visit Your Group
Y!7 Toolbar

Get it Free!

easy 1-click access

to your groups.

Yahoo!7 Groups

Start a group

in 3 easy steps.

Connect with others.

.

__,_._,___