How much wind was there? The sails look very flat and the mainsail leech very open in which case more halyard tension, more flexible battens or more batten tension can be tried, along with some easing of the outhaul and the jib sheet.
Does the mast rotate independantly of the boom? If so, the trailing edge should be rotated so it is about 45 degrees off centre, to leeward.
What happens when you point higher than a reach (sails flap, rudder stalls, boat goes sideways, can't steer, luffs into the wind, etc)?
It is difficult to tell sail shape from side on photos. Try and get them looking up the sail from about mid way along the foot, see http://www.northsails.com/nz/TECHNOLOGY/SailScan/tabid/8364/language/en-US/Default.aspx) for how to do it, what telltails and stripes should be on the sail and how the sails should look.
If it is not too windy, set the boat up on the marina with the sails pointing as close to the wind as possible (windward luff telltales just about to flutter) and as close to the optimum shape (experiment to see not only what works, but the effect of each control) as you can get. Then take the photos up the sail from mid foot. Note the compass direction of the boom, then shunt and do the same on the other tack, still tied to the marina. Compare the compass angles. This will indicate how much of the problem is the sails.
Then remove all extra weight and windage, clean the bottoms and rudders and go sailing. Start on a reach, then slowly head up into the wind, sheeting on as the ww telltales on the jib start to flutter until the boom is on the centreline. Observe everything as you do so, and let us know. Also note wind strength, halyards tension, outhaul location (mark it so you can replicate it), jib sheet tension, and car location on the track.
regards,
rob
On Tue, Oct 18, 2011 at 10:52 AM, Herb <squirebug@yahoo.com> wrote:
Dear All,
I have uploaded some of the pictures I took last Sat. to Sangduennoi 20111015. More will follow later as it is taking a very long time to upload the photos 1 by 1. Yahoo will not let me upload them in batch. Any advice on sail shape will be very welcome.
Last Sat. our best shunt was at least 150 degrees by GPS - most were close to 180. At this point the boat is unusable because we can't sail close enough to the wind to leave the marina. The wind was blowing into the marina and all we could do was reach back and forth in front of it. All progress to windward was by outboard.
It is not just me. Gua (who did all the work on the boat and is a good seaman) can't do any better.
Any help will be most welcome!
Best regards
Herb
--- In harryproa@yahoogroups.com.au, "tsstproa" <bitme1234@...> wrote:
>
> Its sounds like you have enough sail area up to be powered were you?
>
> Why not try two bidirectional boards down all the time connected and counter rotating to a max angle of 30 degrees bidirectional symetrical foils for to aft. You get very precise handling and can crawl to windward if you wanted to.
>
> High buoyant low draft proa with only a single steering board you'll need at least a 1 1/2' wide x 5- 6'deep steer board. For helm balance in a greater range of condition. Key note here is that I said "greater range of conditions" .
>
> Todd
>
>
>> --- In harryproa@yahoogroups.com.au, "Herb" <squirebug@> wrote:
> >
> >
> >
> > Hi Todd,
> >
> > Sangduennoi has 2 rudders, but they lift instead of rotating, so only 1 can be in the water at a time. It is located a little aft of the end of the main boom.
> >
> > I think the original sail area was designed to be about 20m^2, but the mast broke last year and was shortened so now both main and jib are at the first reef. I would guess the total area now is about 14 m^2. Rob or Doug do you know for sure?
> >
> > The shape of the jib is poor both because of the sag and because we rolled it around a plastic pipe to organize it, but I think it is affecting the shape and now it has to be pushed across during the shunt instead of crossing on it's own.
> >
> > Hope to have useful pictures up next week.
> >
> > Best regards
> > Herb
> >
> > --- In harryproa@yahoogroups.com.au, "tsstproa" <bitme1234@> wrote:
> > >
> > > How many boards where down 1 or two? What size sail area was up?
> > >
> > > Todd
> > >
> > > --- In harryproa@yahoogroups.com.au, "Herb" <squirebug@> wrote:
> > > >
> > > > Dear All,
> > > >
> > > > Sangduennoi (nee Sidecar) entered Thai water for the second time last Sat (8 Oct.)
> > >
> > > >
> > > > Only concern at this point is that we couldn't go to windward at all well. I estimate our best shut was about 120 degrees. This wasn't by compass or GPS, but there are several islands and headlands that make estimating angles pretty easy in the Ocean Marina area (Sattahip near Pattaya - about 12N 100E). Any suggestions on how to improve windward performance?
> > > >
> > > > Don't have any pictures yet as I accidentally deleted them from the phone.
> > > >
> > > > Best regards
> > > > Herb
> > > >
> > >
> >
>
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