G'day Tony,
Just you and me so far.
I am confused about the outhaul. The outhaul influences the shape of the sail. The outhaul is under more tension in heavy air and upwind. The ajustment to change the shape will be small (inches) - tweeking and untweeking. Maybe in a nonracing mode little will be required.
OK then, what is the mechanism used at the boomend? Seems to me all the forces are tugging at the end of the boom - loosefooted clew and the sheet. I'm inclined to think that the loads should be spread out here. How is this done and what is the best way.
I guess I'm not sure what the forces are at the gooseneck. Pulling at the sheet with a belly full of wind would put a strain on that fitting, no? In the unlikely event that the boom gets into an unnatural angle with the mast, I'm just asking if there is an optimum fitting that won't be as vulnerable as one 338 has.
When I look at the boom and imagine this as a strut in the loosfooted main setup, I can't see what influence the vang can have without bending the extruded boom. It is rather meager sectioned. If you curve the boom by hauling it down with the vang, areen't you increasing the chord in the sail? Buckling the boom is definitely something to consider here!!
I'm concerned about what is the strongest and most elegant way to upgrade what I have, if possible. I'm convinced loose foot IS the way to go.
[I get into esoterica I know, but as long as we're on the subject of the main: I'm going with a tilted up boom of the same original length so I can get some headroom in the cockpit aft of the dodger. Not going to change the goosneck position.
Also, regarding a straight leech on a cruising sail, I may be far off base.
Raising the outboard end of the sail will decrease the area. I have just read and been influenced by Steve Dashew's comparison of a triangular sail with a roached sail. He points out that "the effective aspect ratio of the roached sail will be much hgher..." and "the roached main has a much better tip shape and less tip loss which is a major contributor to induced drag." Roaching 338's will add area back. Ohoh, there's that pesky backstay!
I know we are not talking about sail shape especially from the cruiser's view.
It is interesting tho that cruisers now have huge roached sails because of high aspect ratio mains, sometimes requiring full battens up top and shorter ones controlling the leach. Dashew says the real driver on a cruise rigged boat is the mainsail, rather than the genoa or geneker. Have to talk with Hogin about this. I didn't want ANY pockets because, as I read, most repairs to the sail are in these places.]
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