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Forums28
Topics4,054
Posts19,272
Members1,062
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Most Online1,909 Jul 28th, 2026
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Joined: Jun 2008
Posts: 137
Senior Member
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Senior Member
Joined: Jun 2008
Posts: 137 |
I am in the process of ordering a new main and am leaning towards optimising my Phrf....I really enjoyed the thread about code6 - extended roach I am strongly considering to extend to the max (24 cm) and take the 9 second penalty but suddenly thought of potential mast failure I do not have a spreader bar kit on my mast presently Am I flirting with disaster going for a full roach main?
Taras
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Joined: May 2007
Posts: 2,685 Likes: 1
Past J/30 Class President
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Past J/30 Class President
Joined: May 2007
Posts: 2,685 Likes: 1 |
Taras - I think anyone who has not had the spreader bar fix is flirting with disaster after seeing the condition of the rivet holes in the mast for the spreaders prior to the fix.
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Joined: Jun 2008
Posts: 137
Senior Member
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Senior Member
Joined: Jun 2008
Posts: 137 |
Well, my mast is down for the winter,...I will have a close look at it Remember Bill, I sail on interior waters,...waves may hit 18" - 24" chop when the winds are 25Kts+ I remember discussions that the fix was really necessary for off-shore racing
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Joined: Oct 2009
Posts: 381
Senior Member
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Senior Member
Joined: Oct 2009
Posts: 381 |
I have not done my preader fix yet. It is on my "to do" list.
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Joined: Oct 2007
Posts: 179
Senior Member
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Senior Member
Joined: Oct 2007
Posts: 179 |
it really depends on the past life of each individual boat, when I did the fix in 2008 after 28 years of use there was zero sign of wear and tear on the rivets, one word of caution, the old brackets are not necessarily installed at exactly the same height, if that is the case the thru bar installation will have unequal vertical angles which is difficult to notice until the mast is back up and can be viewed from a distance
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Joined: Jun 2008
Posts: 137
Senior Member
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Senior Member
Joined: Jun 2008
Posts: 137 |
I checked with my sail maker (UK-Hasley) and they said that the extended roach will not change the "righting moment" of the boat,...thus the mast should not have any (much) extra load
Comments?
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Joined: May 2007
Posts: 2,685 Likes: 1
Past J/30 Class President
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Past J/30 Class President
Joined: May 2007
Posts: 2,685 Likes: 1 |
I heard a different story from a guy at Hood sails during a forum at West Marine who described the same type "full roach" mod to make a square top sail on a rig that wasn't designed for it. He said it worked great in light air, but brought down the rig the first time the wind was up.
If you want a real knowledgeable opinion, shoot Rod Johnstone an email and ask what he thinks.
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Joined: Oct 2010
Posts: 203
Senior Member
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Senior Member
Joined: Oct 2010
Posts: 203 |
Maybe if three of us Taras, Natural High and me, Conundrum all order the spreader bars, Rig Rite will go into production for us.
Don King
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Joined: Jun 2008
Posts: 137
Senior Member
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Senior Member
Joined: Jun 2008
Posts: 137 |
Bill, I took your advise and shot Rod an email I received an answer within an hour,....impressed I am
Here is what he said: Dear Taras, "I would stick with the Regular class main and class 163% LP genoa. If I were to juice up the sail plan for better light air speed I would go with a bigger spinnaker on a longer pole to go faster downwind. and reaching. Maybe up to 13.5' on the spin pole and 24.3' on the max spin girth. Because the max spin luff length is based on .95*(I^2+SPL^2)^0.5, the spin luffs can also be correspondingly longer. The girths are based on 1.8*Pole length. How much would that cost on your rating in your PHRF fleet? It might be worth it if it costs you less than 6 sec/mile on your PHRF rating."
Rod
Though when asked if was a merit or detriment to boat performance to have the extended roach he replied:
"A few inches of extra roachin main would definitely be faster in light air upwind and all the time downwind."
So I decided to pair down my roach size and increase it only 5 -6 inches as oppose to 10-12 inches
Thanks for the suggestion
Taras
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Joined: Apr 2000
Posts: 679
Governor at Large
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Governor at Large
Joined: Apr 2000
Posts: 679 |
As a one design guy I rarely get involved in discussions about modifications. Unlike most PHRF specs that use multiple measurement points, J/30 Class rules only specify a half width (5.12.2.3, aka mid girth). Numerous attempts have been made to increase roach at 3/4-7/8. You could add runners, a backstay flicker, or drop the halyard before every tack, but if not, don't be surprised if you have trouble getting the mainsail past the backstay. It will drive you crazy downwind, especially in light air.
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