ROLLER FURLING MAIN

[Tim Leighton]

I'm sailing a 2002 Catalina 400 with a roller furling main and 135% geona. Although I understand that an ever increasing percentage of cruising sailboats are coming with roller furling mains, I have been totally unable to find specific sail trim information for this type of loose footed sail. Are there any publications that directly discuss sail trim of loose footed mains or can you provide a short primer here (especially on outhaul positioning)? Thanks!Tim LeightonS/V "Magic"Chesapeake Bay

 

[Bill Colombo]

R/F MainTrim

Tim, A roller furling main is basically trimmed the same way as a standard mainsail. The fact that it is loose footed makes it easier to flatten or shape than a sail with an attached foot. Nowadays every racing mainsail we build and at least half of the cruising mains are loose footed. A loose footed sail will get flatter than a standard foot main, simply pull the outhaul tight and the foot goes straight and flat for windy conditions. You can power up the bottom of the sail easily by easing the outhaul since there is nothing to restrict the amount of curvature than can be aceived. On a R/F main you don't want to over-ease the outhaul. Since the sails have no battens they tend to get a bit round in the leech area and you don't want to add to this by making it more full as well. Halyard tension on a R/F main is also critical. Too much and the draft goes too far forward and the unsupported leech may flutter. Too little and the sail may be draft aft causing the boat to heel excessively without adequate speed.Thanks,Bill ColomboDopyle Sailmakers

 

[Jordan Ruzz]

RF Trim Tricks

Tim,I sail a Beneteau 321 with a RF main. One of the un discussed keys to sail trim is the height of the boom with respect to the sail foot, or more specifically, the angle that the outhaul makes with the boom. Its similar to car positioning for a headsail. If the boom is low with respect the the sail foot, the pull of the outhaul will be more down (tensioning the leach) than aft (tensioning the foot). I find that if I want to flatten the foot of the sail, I've got to allow the boom to rise, to get more direct tension aft. THEN, by retightening the mainsheet, the leach tension can be adjusted. Finally, use the traveller to position the boom.Hope this helps.Jordan