Sloop vs. Fractional Sloop vs. Cutter - Page 2

Jeff_H · #11 (**permalink**) 02-02-2004

OOPs, Forgot the Soverel 33 F$ and the Soverel 30 MH$

Jeff

msl · #12 (**permalink**) 02-02-2004

Thanks very much. It is just the kind of "busy" I never grow tired of...
Mark L.

msl · #13 (**permalink**) 02-02-2004

...and one more comment to confuse matters. All the boats you listed are spectacular in design and performance, I''m certain.
So there sits a Pearson Triton, fractional rig and all, just to confuse things. Well, not really.
But for the sake of discussion, how would handling change if a Triton (or any of the others you listed) was modified from a fractional to a masthead rig? What sailing characteristic(s) would we notice (mastbend/backstay tensioning excluded)?
msl

Jeff_H · #14 (**permalink**) 02-02-2004

In their orginal form, Tritons had a fair amount of weather helm. As a result, to mitigate the weather helm, a number of them were converted to masthead rigs with the addition of a bowsprit which worked reasonably well. Tritons did not have flexible rigs, so as you note, some of the advantages of a fractional rig related to ease of control of the degree of power were absent. On the other hand Tritons did have the advantage of having smaller headsails to handle.

It is important to understand that in the early days of the Bermuda rig, almost no boats were built as a masthead rig. Experiments reported in Manfried Curry''s book showed that fractional rigs were capable of generating more drive per given square foot of sail. It was only with the measuring loophole in the CCA rule (and later IOR rule) that did not tax the area of a genoa beyond the 100% foretriangle that masthead rigs became popular.

So back to your example of the Triton, if you kept the sail area equal you would loose drive and speed. If you simply increased the forestay length to the mast head you would end up with an extremely high aspect ratio sail that would work well to windward but which would be hard to keep properly trimmed and which would not work well off of the wind. Of course going to a masthead rig of equal sail area and mast height as the original fractional rig would result in a boat that would heel more as well.

Jeff

Epiphany · #15 (**permalink**) 02-02-2004

Jeff H:

Thanks for your very thorough explanation of the relative advantages of fractional rigs. However, unless I''m mistaken, your list of favorite boats was focused more on performance types. I''m not as interested in performance as I am in stability. I want a boat with sufficient displacement and a full keel with enough sail area forward to facilitate heaving to in heavy weather. What boats would you recommend given these criteria, and would a fractional rig hold as many advantages over a masthead rig given a desire for stability as opposed to performance?

Jeff_H · #16 (**permalink**) 02-02-2004

My list included a pretty wide range of boats. I believed that I was responding to a request for a coastal cruiser but included boats that ranged from stripped out racer/cruisers to boats like my own that were intended for distance offshore voyaging in safety.

If you are truely concerned about primarily about stability, I have no idea why you are looking for a heavy displacement/full keel boat. As I have explained before and unfortunately do not have the time to explain in detail tonight, newer fin keel boats tend to have a much lower VCG (more ballast stability) than more tradition full keel boats especially relative to their drag. This means that they not only have greater stability over a wide range of heel angles but they also can get by with much less sail area in a blow.

When you say,"I want a boat with sufficient displacement and a full keel......to facilitate heaving to in heavy weather." I think that you have a very mistaken and outdated idea about what allows a boat to hove to safely in heavy weather. My fin keelers have generally hove to easier than the full length keel boats (Folkboat and 1939 Stadel Cutter) or long keeled boats (Pearson Vanguard) that I have owned.

Fractional rigs work best with high stability, easily driven hulls and so are ill suited to the high drag/low stability of a heavy displacement/full keel boat. If you are going the heavy displacement/ full keel route you pretty much are stuck with the relative inefficiency of a very large sail plan carried low and at that point the best compromise in order to stretch out the sail plan horizontally is probably a cutter rig with all of the disadvantages that come with a cutter. It is very dated thinking but certainly reflects one posible route.

Respectfully
Jeff

DelmarRey · #17 (**permalink**) 02-04-2004

Might I ask where the position of the mast on a fractional rig is in relation to the LWL or OAL, which ever applies? And compared to the position of a masthead rig?
From pictures I''ve seen it appears to be in the 30-40% foreward section. And if so, how is the mast stepped over the keel, which appears to be on the centerline abeam (the keel that is)?
Also, are there any mast height differences between the fractional and the masthead rigs and is it much trouble converting a masthead to a fractional rig? Which I''ve been contemplating, obviously.
Thanks, ......Del

Jeff_H · #18 (**permalink**) 02-05-2004

Generally the mast on a fractionally rigged boat is further forward than it is on a masthead rig. The keel on a fractionally rigged boat is also generally a little bit forward of the position that it would be on a masthead rig. (This is part of the reason that Fractionally rigged boats will often track a little better than a mathead rig for an equal keel area on the other hand this is also the reason that Frac''s tend to kite more on the anchor.) The mast on a fractionally rigged boat is usually taller than the mast on a masthead rigged boat and these days are typically a tapered spar. Other differences is that a fractionally rigged boats used for cruising generally have swept back spreaders (10-15 degrees),usually do not have any forward lowers and usually have a single shroud chainplate positioned aft of the mast.Depending on the design of the boat, in most cases it is a pretty big job to convert a masthead rigged boat to a fractional rig.

Jeff

DelmarRey · #19 (**permalink**) 02-05-2004

Thanks Jeff for the reply! It appears there is more work than reasonable to convert. It would be better to just buy a vessel already set up for Frac''l rig. I have a tall rig (57'' mast) but its obviously the wrong style. I have double spreaders, with the shrouds directly p/s. I have cosidered a longer boom for more main sail but don''t know how that would affect the helm.

Del

genethompson · #20 (**permalink**) 02-05-2004

Del
Jeff will be able to give a better answer, but a longer boom will help in light winds where the extra weather helm won''t be that much of a problem. Better would be a main with full upper battens and a full roach. You didn''t mention what your main is like. A good (new) main sail will make a big difference.

Gene