Luff Considerations - Sail Magazine

Luff Considerations

Bob Boller of Benicia, Califonia, asks: "I have three headsails for my 1980 Catalina 30 and their LPs are 85, 110 and 150. As it does on many cruising boats, the bow pulpit interferes with the lower portion of the sails, especially the smaller two. What do you think about slightly raising the tacks of the sails up the forestay? What effect will that have on the performance
Author:
Publish date:
Social count:
0
LuffPhoto1

Bob Boller of Benicia, Califonia, asks:

"I have three headsails for my 1980 Catalina 30 and their LPs are 85, 110 and 150. As it does on many cruising boats, the bow pulpit interferes with the lower portion of the sails, especially the smaller two. What do you think about slightly raising the tacks of the sails up the forestay? What effect will that have on the performance of the sails?"

Win Fowler replies:

If this bothers you, by all means raise the sail up the forestay. There are both benefits and drawbacks to doing this, but all are relatively minor. The sail’s center of effort will be raised, which produces more heeling moment for the same sail area. Also, when the tack is attached to a luff pendant, there’s a chance the tack might move away from the axis of the forestay under load and that could perhaps damage the luff tape where it enters the feeder for the luff extrusion.

Any added heeling moment, however, will be pretty insignificant, and the risk of a stretched tack position can be handled by keeping sufficient tension on the sail and perhaps lashing the tack ring to the luff extrusion so it remains at the same distance from the extrusion as it would be if the tack were attached to the roller-furling drum.

When done correctly you won’t have any more chafe from the pulpit and you’ll have better visibility under the sail. You will benefit from a bit more apparent wind velocity coming from further aft but you will also have that small amount of increased heel. The effects of both are small, so you needn’t waste time calculating the results.

Related

180621-X01-Landing-Page

Volvo Ocean Race Cliffhanger

After racing over 44,000 miles round the world and battling their way past the world’s great capes, including the Cape of Good Hope and Cape Horn, it’s all come down to the final 700-mile leg from Gothenburg, Sweden, to the Hague. Brunel, Mapfre, Dongfeng: going into the ...read more

Stearns Photo

Racing the Solo Mac for a Cause

There are plenty of reasons to do a Chicago-Mac race, and Rich Stearns, who has done literally dozen of ‘em should know. This year, though, he’s doing the Solo-Mac for an especially important reason: to help those with prostate cancer.“Two years ago, I was diagnosed with prostate ...read more

TOTW_PromoSite

SAIL's Tip of the Week

Presented by Vetus-Maxwell.Got a tip? Send it to sailmail@sailmagazine.comRafting dangerOne unseen danger when sailing yachts lie alongside one another for a convivial night is that if they happen roll to a wash or begin to move in an unexpected sea, the spreaders can clash ...read more

180615-01 Lead

A Dramatic Comeback in the Volvo

After winning three of the last four legs in the Volvo Ocean Race (and coming in second in the fourth), Dutch-flagged Brunel is now tied for first overall with Spanish-flagged Mapfre and Chinese-flagged Dongfeng following the completion of Leg 10 from Cardiff, Wales, to ...read more

MFS-5-2018-Propan-SP02

Tohatsu LPG-powered 5hp Propane Motor

Gassing it UpTired of ethanol-induced fuel issues? Say goodbye to gasoline. Japanese outboard maker Tohatsu has introduced an LPG-powered 5hp kicker that hooks up to a propane tank for hours of stress-free running. Available in short-, long- or ultra-long-shaft versions, the ...read more

180612-01 Landing lead

Painful Sailing in Volvo Leg 10

It’s looking to be a case of feast or famine for the 2017-18 Volvo Ocean fleet as it continues the epic struggle that has been Leg 10, with it having been all famine thus far. Painful is the only word to describe the light-air start in Cardiff, Wales, on June 10, as the 11-boat ...read more