David wrote:

Practicalities matter. Where is one going to get hold of a mast to hang your 71.8 sqm sail on. Where, in N America, is such a mast to be found?

That sounds as the biggest challenge, and that's why I have suggested the 61.5sqm alternative, or something in between.

However, there are other materials, Oregon Pine, for instance. Both Samson in Stavanger, and Peregrine in Greifswald, Germany have been rigged with wooden masts.

Arne

PS: Come to think of it. I struggle with believing that there are not 6m sections available of sufficient diameter in the US. One can of course build a mast from 2-3 sections, as others  (Jami Jokinen for instance) have done.

Anonymous wrote:

Arne,

I know that a 10in dia mast will carry a 55 sqm sail, because I've been there and done that. I don't know whether it will carry a 71.8 sqm sail from personal experience, so I don't feel it wise for me to recommend doing that, and I would have my doubts about it. These flagpoles go down to a diameter at the top that I consider too small for a mast, and the top few metres need to be trimmed off. So a 50ft flagpole gives you a 44ft mast at best.

Sorry, mate, but you have been there and done that in a lighter boat than the Gazelle. It is not the sail area which breaks masts, but mainly the righting moment (plus pitching) of the vessel. The Gazelle, being about twice the displacement of Tystie, will probably put a lot more strain on the mast even when the sail area is the same. This is because the Gazelle would stand up to the sail longer than the smaller vessel.

A

Max, the Gazelle is a good sailing boat as is, but lacks the drive upwind to push through any appreciable sea state. Tweaking the sail design to get more power close hauled would do wonders for performance offshore. Sailing this boat is all about balance, with two mast it's quite easy to keep her dialed in. One can even get half a panel reefing using the lazy jacks pick up (or not) the outboard end of the sail. My complaint against the jib is having to go out on the sprit to furl it in heavy weather. 

Arne,  the jib is essential for balance. Could it be replaced by a raked forward junk sail in the bow? I don't know how to figure if it would get that sail far enough forward to balance.

The mainsail on this boat is a workout to hoist with a four part tackle!  I added rubber hose to the parrels to prevent chafe last year and that has made getting the last two panels up quite difficult with wind in the sail. I can't imagine pulling up a sail twice this size without winches.

Attached is a drawing from David Chidell of their modification to Tin Hau. This is what I am considering doing to ease the sail handling problems. My concern is that it doesn't look possible to use a four part tackle on it and it may be too hard to sheet in the main in a good breeze.  With a four part going to the euphroe it can take a pretty good pull when the wind is more than 20 knots the way it is rigged now.

I have seen a picture of a Gazelle ketch rigged, both mast were placed further aft than with the traditional schooner rig.

Dave

Wouldn't those sail plans considerably raise the CE? The Gazelle is quite shoal. I don't know if it can stand up to a tall sail plan.

Regarding the mast placement, it would be possible to move the foremast placement forward as it falls in a v-berth, but not backward into the cabintop. The cabintop on a Gazelle is plywood, not steel. The aft mast would be possible, but difficult, to move backward, because just aft of its current placement is the engine. So you'd have to build some sort of step bridging the engine (?). Doesn't sound great for engine maintenance, ease of installation, or mast bury (but what do I know?). If you go further aft than the length of an engine it becomes possible again, by building a step that bridges the shaft.

What could be done with the current masts, keeping the stays and the jib? Or at least with the current mast placements, and keeping the stays and jib? Could you gain a lot by simply changing the sail shape and sheeting method, and adding camber?

Max

Arne,

I know that a 10in dia mast will carry a 55 sqm sail, because I've been there and done that. I don't know whether it will carry a 71.8 sqm sail from personal experience, so I don't feel it wise for me to recommend doing that, and I would have my doubts about it. These flagpoles go down to a diameter at the top that I consider too small for a mast, and the top few metres need to be trimmed off. So a 50ft flagpole gives you a 44ft mast at best.