Subject: [harryproa] Re: Rig comparisons
From: "Robert" <cateran1949@yahoo.co.uk>
Date: 6/5/2008, 7:27 PM
To: harryproa@yahoogroups.com.au
Reply-to:
harryproa@yahoogroups.com.au

Apologies, Todd,
I wasn't thinking.
Clearly your A frame rig and the traditional crabclaw can balance
without underwater appendages. I wasn't thinking about moving the mast
or what ever one calls it if it is an A frame.
Free standing cuts down on the air drag of stays and allows a higher
roach for mast height unless you go to a crab claw or some other rig
that provides its own support up high and allows gusts to be spilled
I think your systems are excellent designs and a large improvement
over other modern stayed rigs. The traditional crab claw is still hard
to beat for simplicity, but your ideas should be easier to shunt.
We all much appreciate the model testing you have done and really have
learnt a fair bit from them.In fact, it has convinced me to use a
windsurfer rig that can be changed from one end of my little proa to
the other, supported by a small A frame at the point where the boom is
tied. I can't see much advantage over the crabclaw, but there are
plenty of old windsurfer rigs around.
Robert
--- In harryproa@yahoogroups.com.au, "tsstproa" <bitme1234@...> wrote:
>
> To state you need a team of gorillas to adjust CO and leeway
> resistance or design an entirely different boat then you missed the
> point and proof done with models.
>
> The K proa is a nice project but not what I have in mind.
>
> My weather stayed mast configuration would be canted toward leeward
> and mastbase just outside of weather rail of leeward hull. The fore
> most sail would be of narrower higher aspect ratio and the second
> sail aft would be deeper lower aspect ratio. Canard like, main wing
> aft smaller wing foward.
>
> What is the real difference in freesatnding vs stayed really.
> Exchange/difference in forces inorder to carry sails.
>
> Fritz is another character. Doesn't allow me respond to post on his
> groups. Who privately emails me to tell me how stupid I am along
> with how I'm an >>>>>ANTI AMERICAN<<<<<< living in US. Hate mail
> with underling terrorist threats. Wonder how the FBI or those Home
> Land Security agents are gonna view those emails!?
>
> So for now good luck to all you proa nuts out there. I really have
> nothing to say or ideas to share that are really worth while for
> arguments sake. Just don't fall back, following tradition instead
> lead away, anyway!
>
> You can check youtube now and then under tsstproa to see some of
> what I'm up to. Working on a r/c square harry, new 24''windward hull
> done.
>
>
> Bye for now,
> Todd
>
>
>
>
>
>
>
>
>
> --- In harryproa@yahoogroups.com.au, "Robert" <cateran1949@>
> wrote:
> >
> > -If you want a boat with minimum underwater appendages, you either
> get
> > a team of gorillas to run from one end of the boat to the other to
> > adjust CO leeway resistance or you go to a proa tri.
> > You put the rig in the middle size weight carryingcentre hull and
> > have the sheets leading to the smallest ww hull. You can then argue
> > about stayed and unstayed masts or schooner rig, but it brings the
> CO
> > lee resistance needed well forward.
> > It vastly improves the staying base if you wish to go that way or
> an
> > unstayed Baleestrom rig would balance it nicely with only a small
> > rudder for fine control. Or go to a schoooner rig and control it
> with
> > playing the sheets. I much prefer unstayed masts over stayed as,
> apart
> > from the compression loads, you don't have to have such a stiff
> > platform to keep the rig under control. When you consider how the
> > loads are distributed on a sail, a catenary (tapered) does not
> cost
> > nearly as much weight as first appears. Take away the turbulence
> > caused by the stays (unless you have sails hanging of them like
> Fritz
> > and causing extra drive) and the ability to rotate a high roached
> sail
> > to avoid getting caught aback and be able to ref in nasty
> conditions
> > and it looks even better.
> > Isn't there a couple of Pacific Proas for sale? Swap the short
> > outrigger for a long assymetric one and call it the lee hull, and
> then
> > take the short hull and stick it nice and high to ww and you have
> > the makings of a nice boat. Only problems are that it is a bit
> heavy
> > in the ww hull having to make it strong enough to handle the
> sailing
> > loads and have accommodation at the same time (Sorry for stirring
> (or your not steering):)
> > things up, but it actually makes sense to me)
> > Robert-- In harryproa@yahoogroups.com.au, "Robert" <cateran1949@>
> > wrote:
> > >
> > > -IMHO That windward staysail is what allows the boat to achieve
> > > balance, otherwise the boat would need the lee resistance
> further back
> > > and the vector fin would make the boat head up to wind,
> > > RObert-- In harryproa@yahoogroups.com.au, Mike Crawford
> > > <jmichael@> wrote:
> > > >
> > > > That windward staysail is awfully weird, isn't it? Perhaps
> it's
> > > there
> > > > to help keep the boat down when the foil isn't working. ;-)
> > > >
> > > > Nope -- no perfect solution. But that's the fun of it all.
> If
> > there
> > > > were a perfect solution, we'd just settle on it and move on.
> I love
> > > the
> > > > idea that one asks the impossible of a boat design, and then
> spends
> > > > months or years figuring out what the best compromise is for
> all the
> > > > competing priorities.
> > > >
> > > > - Mike
> > > >
> > > >
> > > > Arto Hakkarainen wrote:
> > > > >
> > > > > I am familiar with Fritz Roth work. And I remember his
> > > > > way of net conversation...
> > > > >
> > > > > But I would not trust on foil alone to keep large boat
> > > > > from capsizing. Too many things may happen that
> > > > > prevent the foil to balance the boat and you only need
> > > > > one occasion on wrong moment... Let's think if
> > > > > something tangles to foil or boat stops on a wave or
> > > > > whatever that makes the foil not to provide the
> > > > > counterforce needed to keep the boat upright. Wind
> > > > > usually doesn't stop heeling the boat at the same
> > > > > time. Weight to windward and long buoyant hull to
> > > > > leeward just seems much better. Minimum number of
> > > > > foils and underwater appendices is also to my liking.
> > > > >
> > > > > Tom Speer also pointed out one thing why one of the
> > > > > staysails on Fritz Roth's proa is not good: the sail
> > > > > on windward stay pushes boat down effectively
> > > > > increasing displacement. Not good.
> > > > >
> > > > > Staysail rig could be very effective and easy on a
> > > > > proa. Backwinding is an issue but I haven't found
> > > > > solution yet. Easyrig is good in that respect. No
> > > > > problems backwinding, easy to shunt. It has a lot of
> > > > > merit. No perfect solution yet I suppose.
> > > > >
> > > > > Arto
> > > > >
> > > > > --- Mike Crawford <jmichael@ <mailto:jmichael%40gwi.net>>
> wrote:
> > > > >
> > > > > >
> > > > > > You share some ideas with other people on the proa
> > > > > > leading edge.
> > > > > >
> > > > > > In this case, with Fritz Roth, who designed and
> > > > > > sails the vector fin proa:
> > > > > >
> > > > > > http://proadesign.com/ <http://proadesign.com/>
> > > > > >
> > > > > > I strongly considered his design at one point, but
> > > > > > there were two
> > > > > > showstopper problems for me.
> > > > > >
> > > > > > The first was that the mast would not do well if
> > > > > > caught aback, which
> > > > > > could be solved with a good harryproa design for the
> > > > > > mast, hull, and
> > > > > > beams (though the mast does intrude on living
> > > > > > space).
> > > > > >
> > > > > > The second, as Rob has pointed out, is that the
> > > > > > wonderfully-effective
> > > > > > vector fin becomes useless once it catches a raft of
> > > > > > seaweed or a large
> > > > > > plastic bag. Considering that it's the fin that
> > > > > > keeps the boat upright,
> > > > > > this is a serious problem. The fin is also of
> > > > > > little use when the boat
> > > > > > is not moving, such as during a shunt, or when
> > > > > > stalled in a seaway.
> > > > > > That would be bad news in big winds. Fritz claims
> > > > > > that the boat will
> > > > > > automatically weathercock, but has never explained
> > > > > > how.
> > > > > >
> > > > > > Neither of these problems has to do with the rig,
> > > > > > which has proven to
> > > > > > be fast and useful. At least in Fritz' own unique
> > > > > > description. He's a
> > > > > > bit flaky, and his idea of debate is simply
> > > > > > ridiculing his opposition
> > > > > > without any real data, but he is out there building
> > > > > > and sailing his own
> > > > > > designs, so in my book he deserves a certain measure
> > > > > > of respect.
> > > > > >
> > > > > > My personal reason not to use a main with
> > > > > > staysails is that it forces
> > > > > > you to use a small-roach mainsail in order to fit
> > > > > > inside the stays.
> > > > > > It's not the end of the world, but it does cut down
> > > > > > on sail area high
> > > > > > up. As Garry Hoyt, the designer for the Alerion
> > > > > > Express 33, went with a
> > > > > > taller full-roach mainsail and a self-tacking jib
> > > > > > because, in his
> > > > > > argument, this presents as much sail area as the
> > > > > > genoa would have added
> > > > > > to the mix, and it keeps that area high up where it
> > > > > > will do the most good.
> > > > > >
> > > > > > (todd -- that obviously works towards your
> > > > > > argument to use the tall
> > > > > > single sail instead of the schooner rig).
> > > > > >
> > > > > > But that doesn't stop it from being effective.
> > > > > > You could get a lot of
> > > > > > sail area, with a low center of effort, with
> > > > > > thin-luff leading edges,
> > > > > > using one or more staysails.
> > > > > >
> > > > > > The designer of the Mast Aft gamefishing catamaran
> > > > > > (
> > > > > > http://www.runningtideyachts.com/gamefishing/
> > > > > <http://www.runningtideyachts.com/gamefishing/> )
> > > > > > argues that the
> > > > > > staysails are both more efficient and more
> > > > > > controllable than a mainsail.
> > > > > >
> > > > > > - Mike
> > > > > >
> > > > > >
> > > > > > Arto Hakkarainen wrote:
> > > > > > >
> > > > > > > Your videos and testing got me to think again the
> > > > > > rig
> > > > > > > issue. Having furling staysails is easy, light,
> > > > > > > effective and elegant. All very good features.
> > > > > > Having
> > > > > > > two sails is more effective and gives more chances
> > > > > > to
> > > > > > > have the sails adjusted to windspeed. Of course
> > > > > > having
> > > > > > > less strings to pull makes shunting faster and
> > > > > > easier
> > > > > > > so one sail has its merits. Unless of course there
> > > > > > is
> > > > > > > not two inner staysails but one middle sail that
> > > > > > is
> > > > > > > fast and easy to shunt.
> > > > > > >
> > > > > > > Following this line of thought I got an idea that
> > > > > > may
> > > > > > > be totally crazy. Why not have to large staysails
> > > > > > on
> > > > > > > furlers, one on each end of the boat. Then in the
> > > > > > > middle would be either dynarig, bolger sail or
> > > > > > similar
> > > > > > > that would be clearly smaller than the staysail,
> > > > > > > perhaps 1/2 of the staysail size. Then according
> > > > > > to
> > > > > > > studies on sail interaction the smaller sail in
> > > > > > the
> > > > > > > middle should make the staysail in front of it
> > > > > > even
> > > > > > > more effective than it would be alone and each
> > > > > > sail
> > > > > > > would be smaller and more easily managed size.
> > > > > > Then
> > > > > > > the lines to pull while shunting would be the big
> > > > > > long
> > > > > > > sheet for staysail and the other a faster shunting
> > > > > > > bolger/dyna/whatever rig.
> > > > > > >
> > > > > > > Now add to this 360 rotating rudders and
> > > > > > possibility
> > > > > > > to connect two furlers so that one sail unfurling
> > > > > > > furls the other. That should make shunting
> > > > > > relatively
> > > > > > > easy.
> > > > > > >
> > > > > > > May be I should quit my day job and become
> > > > > > inventor :D
> > > > > > >
> > > > > > > Comments welcome.
> > > > > > >
> > > > > > > Arto
> > > > > > >
> > > > > > > --- tsstproa <bitme1234@ <mailto:bitme1234%40yahoo.com>
> > > > > > <mailto:bitme1234%40yahoo.com>> wrote:
> > > > > > >
> > > > > > > > Just to let you know the smaller blue easyrig is
> > > > > > > > about 25-30%
> > > > > > > > smaller than orange crab claw. The large claw
> > > > > > seemed
> > > > > > > > to balance
> > > > > > > > better on the proa better than the smaller
> > > > > > esyrig
> > > > > > > > with same size
> > > > > > > > boards.
> > > > > > > >
> > > > > > > > Nothing wrong with larger boards. Different
> > > > > > solution
> > > > > > > > to the problem.
> > > > > > > >
> > > > > > > > Hate to bring this up specially on here but the
> > > > > > only
> > > > > > > > proa I know of
> > > > > > > > using modern stayed mast Is Russell Brown. They
> > > > > > seem
> > > > > > > > to work. Not
> > > > > > > > tring to steer up the hornets nest.
> > > > > > > >
> > > > > > > > What I was thinking for the staysail rig Is
> > > > > > having
> > > > > > > > two sails at each
> > > > > > > > end on off set planes one closest to bow inline
> > > > > > with
> > > > > > > > main hull
> > > > > > > > second sail back from bow set further to
> > > > > > windward
> > > > > > > > off center line
> > > > > > > > from hull.
> > > > > > > >
> > > > > > > > But I'd rather use my Aframe and double Aframe
> > > > > > rig.
> > > > > > > >
> > > > > > > > Todd
> > > > > > > >
> > > > > > > > --- In harryproa@yahoogroups.com.au
> > > > > <mailto:harryproa%40yahoogroups.com.au>
> > > > > > > <mailto:harryproa%40yahoogroups.com.au>, Arto
> > > > > > > > Hakkarainen <ahakkara@>
> > > > > > > > wrote:
> > > > > > > > >
> > > > > > > > > It seems that the crab claw moves faster in
> > > > > > video
> > > > > > > > > showing balestron and crab claw side by side.
> > > > > > Not
> > > > > > > > big
> > > > > > > > > difference but that's how it looks on the
> > > > > > video.
> > > > > > > > >
> > > > > > > > > I agree totally that proa rig needs new
> > > > > > thinking.
> > > > > > > > All
> > > > > > > > > traditional solutions have their problems.
> > > > > > > > Combination
> > > > > > > > > of some features may bring the best solution.
> > > > > > > > >
> > > > > > > > > I agree that staysail only rig has a lot of
> > > > > > merit
> > > > > > > > in
> > > > > >
> > > > > === message truncated ===
> > > > >
> > > > >
> > > >
> > >
> >
>

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