Really glad to hear from you. A very good point abut having the yard mid point of the boom.
--- In harryproa@yahoogroups.com.au, "bitme1234" <bitme1234@...> wrote:
>
> I'm back .....
>
> Cause I really wanted to post to this.
>
> This is pretty interesting stuff. The thing I found using my own JR is when you set up the halyard to be fixed to the center of yard this alone helps to control twist of sail along with having battens running horizontal on sail? I also have my downhaul almost at center on boom. It seems to me having pressure created from wind in front of mast on sail actually keeps the twist out and a uniformed trailing edge without excessive curvature. When I added the camber to my sail with darts I put the camber at mid chord. This may or may not add to better twist control as well. Found the same to be true on trapezoidal sail the battens and (yard pivot)how far in front of mast the yard is plays a roll in controlling twist. The trap sail is flat cut with flat battens. Or this could be just another obscurity of misinformation?
>
> Todd
>
>
>
>
>
> --- In harryproa@yahoogroups.com.au, Rob Denney <harryproa@> wrote:
> >
> A solution
> > (not the one used by James, whose sail has a lot of twist) to the sheeting
> > angle conundrum may be to put up a backstay and run the sheetlets to pulleys
> > tied to it. The sheetlets can then be lead down to the deck and to the
> > helmsman. Less drag as you have one big bundle, rather than a bunch of
> > little ones, and the pull is horizontal instead of near vertical.
> >
> >
> >
> > rob
> >
> >
> > On Sat, May 29, 2010 at 1:56 PM, robert <cateran1949@> wrote:
> >
> > >
> > >
> > >
> > > I had a good look at the sheeting arrangements. They sheet way back to the
> > > stern. This would not really go with the Harryproa configuration of sheeting
> > > back to the ww hull. Posssibly sheet back to a pulley midway betweent the
> > > two bows. I suspect the hinge would have to be made extra strong to handle
> > > the different sheeting arrangements. If the timber wishbones were skinned
> > > with some carbon tow, they should handle the extra loads. It would probably
> > > be worth it aiming for an optimum leeward shape.
> > > I don't particularly like the wrinkles on the ww side. Possibly cutting the
> > > sails on the bias could smooth things.
> > >
> > > I am concerned about the sheeting angles. Hopefully Gardner can sort it out
> > > before I commit.
> > > regards,
> > > Robert
> > >
> > > --- In harryproa@yahoogroups.com.au <harryproa%40yahoogroups.com.au>, Mike
> > > Crawford <jmichael@> wrote:
> > > >
> > > > Robert,
> > > >
> > > > << you could get away with rice bags and still have a reasonable shape>>
> > > >
> > > > Precisely! I'm not sure if it would be a premium racing rig, but
> > > > while cruising, it seems to me that the average sail shape, particularly
> > > > in light winds, would be superior to a bermuda rig.
> > > >
> > > > To get the right sail shape with a single skin takes time, in terms of
> > > > adjusting leech/outhaul/vang (no vang with fixed boom), and money, in
> > > > terms of sail cloth, track, and battens.
> > > >
> > > > Plus, the battens that work at 40 knots will be to stiff for five
> > > > knots, and the battens that work at five knots will be too flexible for
> > > > 40. I'm tired of yanking on my boom to get the battens to switch over
> > > > in light winds. I like to sail, but I'm not the kind of guy who would
> > > > keep three sets of battens on hand in order to have just the right
> > > > strength for the day's winds. So I have a medium-stiff set that
> > > > functions in all winds, but really isn't good for light or heavy weather.
> > > >
> > > >
> > > > <<The strings need not be a big source of drag with dyneema but one
> > > > would need some gloves.>>
> > > >
> > > > Agreed. Though I'd probably try to use dyneema on all the individual
> > > > lines, feeding into a single wider-diameter mainsheet (one shet per bow,
> > > > of course) that would be easier to handle and cleat.
> > > >
> > > >
> > > > <<Some people swear by junk rigs and this makes more sense to me than a
> > > > straight junk.>>
> > > >
> > > > Particularly if you want to go upwind. I'll daysail much more often
> > > > than I go cruising, so going upwind is a big deal. A friend of mine
> > > > says one spends 70% of one's time sailing upwind, and I have to agree.
> > > > If I just go out and back for the day, the windward phase is noticeably
> > > > slower, and covers a lot more distance, than the leeward phase.
> > > >
> > > > - Mike
> > > >
> > > >
> > > > On 5/27/2010 7:29 AM, robert wrote:
> > > > >
> > > > >
> > > > > Hi Mike
> > > > > I am with you on this rig: you could get away with rice bags and still
> > > > > have a reasonable shape; the sheet loads are lighter; it's easily
> > > > > reefable; if the top section rotted out, it would be easy to replace
> > > > > without wrecking the lines of the sails; there's no sail track to buy
> > > > > or jam; and the battens can be low tech. The strings need not be a big
> > > > > source of drag with dyneema but one would need some gloves. I will
> > > > > have to make up my mind before I start trying to set up for making the
> > > > > masts. A simple tapered section makes the most sense and it wouldn't
> > > > > need the bearings of a lot of other rigs.
> > > > > Apart from not being common I am not sure what the problems with it
> > > > > are for a cruising rig. Some people swear by junk rigs and this makes
> > > > > more sense to me than a straight junk.
> > > > > Robert
> > > > >
> > > > >
> > > > >
> > > >
> > >
> > >
> > >
> >
>