J/30 Class Association Forums J/30 Forum The Boat, Sails and Equipment Class legal mainsail

I am shopping for a new mainsail, and am looking at dacron to remain class legal keep the expense down. I have spoken with a few makers about cut and have received differing opinions. One maker says you shouldn't use dacron in a triradial design because the sail looses its shape quickly, you should only do a crosscut with dacron. Another maker says triradial is fine with dacron but specified use of Contender's Radial Wide dacron, which is apparently made specially for radial constructions. A friend has one of these and loves it - the shape is fine after three seasons.

There don't appear to be any class restrictions on the mainsail design. Are there any opinions out there on triradial dacron mainsails? Anyone using one? I'm also considering adding some roach so that the sail will hit the backstay tacking over. Is that legal?

There's relatively few limits on the design of the main. See class rules 5.12.2. There's a max mid-girth measurement of 2621mm which effects the amount of roach. Cloth weight must be at least 6.25 oz.

Does anyone have interest in reconsidering the dacron restriction on mains? An arguement could be made the total cost of ownership is not higher with composites when you consider the longevity. Has anyone been hit with a phrf penalty for a composite triradial main (I wouldn't think so)? I think most sailmakers would steer away from a dacron trirad because you're paying mostly for labor (compared to cross-cut) - the marginal difference for the better material is relatively small. Brad - did you ever build the trirad dacron?

I have a triradial technora composite main that was used in a successful racing campaign (predating me) for 10 years. I have used it as a cruising sail for the last 4. It's worn, but I expect I could race with it.

I have a Pentex tri-radial main made by a super local loft with a tons of J boat experience in Stamford CT. It has worked great for me. I believe the material is class legal, is supposed to be about 50% more resistant to stretch and is lighter than dacron.

You might lookm into this option.

Sailing mostly PHRF, I have tried both Dacron and composites, I do not think that the $$$'s for the composites are worth it for a boat the size of a J-30. They probably are slightly faster out of the box, but age faster. Dacron can still be stretched to a decent shape after a few years. My Dacron main has done well competing against other PHRF boats sailing with composite sails (3rd Key West, 2nd Block Island). However, I do race with composite headsails.

Ed Austin
Chinook

gwylan, thanks for the info - you are correct Pentex is legal and worth considering. My understanding is it is 2x stiffer than Dacron 52, but more porous (probably why it is lighter). Have you raced the Pentex and for how many seasons? Who made it?

I originally meant to gauge the interest in non-polyester fiber/polyester film sails compared to woven polyester.
Thx Seth.hunter@i-stat.com

Ed, thanks for the feedback. Sailmakers and IMS friends are telling me the price of composites is dropping and longevity is increasing, expecially once you bite the bullet for labor to build a triradial sail. But I can't speak from first hand experience. Did you take rating hit for the composite?
Seth

I would take a 1 sec hit for sailing with OD sized sails and a composite main, from 135 to 134. However, I race with PHRF sized sails (155, 11.5" pole, and 180% SMW chute), at 143. I would not take a hit for a composite main in that configuration.

Seth, several years ago we had a bunch of sailmakers come in to advise the Ches_Bay fleet about changes in sail inventory. Since then, we've kept a pulse on advances in technology. At that time, and reiterated since then, the belief was that a "high-tech" material didn't have significant life or speed advantages vice a woven dacron main for a boat with a main the size of a J/30. The key differences between headsails and a main, is that the main has to be suitable for all weather conditions and that the main lives its life on the boom, getting flaked or rolled. It may not be sexy, but it does seem to work well over time.