Big Roached Mains

Dear Linda and Steve: Two years ago I bought a steel kit form Bruce Roberts to build a voyager 495 (L.O.A. 49 ‘- 4") With a longish keel.

About one year ago I bought, directly from you, your book and CD “Offshore Cruising Encyclopedia” which, by the way, is the book I’ve have learnt more from. Pity I didn’t have it before.

You totally convinced me with what you say about mains with big roach. Apart from the technical explanations, your comments about them are: "There is absolutely nothing you can do to an older cruising boat that will increase performance as much as one of these sails, regardless of how much you are prepared to spend."

You have (or at least had) 82% of the rectangle of the luff and foot filled with sail in your actual boat BEOWULF and add “We now realize that we can go farther, adding more horsepower for little cost.”

Exactly two days ago I contacted Bruce Roberts (he is the one who really knows my boat) to ask him to produce me a new sail plan with a main of the same characteristic as the one you had on BEOWULF.

I’ve just been in your web site, as I wanted to buy some more books from you, and you can imagine my surprise when I’ve seen that you have just got a new main and mizzen of considerably different design than the original sails.

I’m really worried now: Have you found anything wrong with them? Could you tell me anything about the new design of your sails? I suppose you are very busy but I would be terribly grateful if you could answer me as soon as possible (the cheque to Mr Roberts has already been sent and now I don’t know whether I have to cancel the order).

All the best, Jose

Hi Jose: Re BEOWULF’s new main and mizzen, the roach profile is almost the same. The changes that have been made are to help it twist off better with wind shear–based on lessons learned from the America’s Cup, Whitbread, etc.

As to your own boat, the only way to get as aggressive a roach as BEOWULF has is to use swept spreaders (BEOWULF’s are 25 degrees) so that you eliminate the backstay. However, this means you cannot run square to the wind. That is OK for a boat that is very fast and pulls its apparent wind forward–but does not work as well on heavier designs.

It is probably best with Roberts to stay with a fixed backstay, so you can run downwind when conditions warrant–and to work with a sailmaker who has experience with past-the-backstay designs–who can optimize the roach profile of the mainsail for you.

You might try contacting Dan Neri––on this subject. I’m not sure if he has the time, but he is the most experienced sailmaker I know in this area. Regards–Steve

Posted by Steve Dashew  (November 30, 1999)

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