Leech Flutter

Jan 22, 2008
763
Hunter 340 Baytown TX
My, less than year old, 108% jib on my 2000 Hunter 340 has pretty bad leech flutter going upwind in anything over 12 knots apparent. The sailmaker says that's normal for a jib with a UV cover sewn on. He says, just tighten the leech line.
Everyone else that will listen to me complain about it, says something isn't right, you only need to use the leech line on old worn out sails. I watch other boats in the same conditions, no leech flutter.
I have to really tighten the leech line to get it to stop. And that puts quite a windward cup in the trailing edge. I've tried every stop on the jib car track, open leech or closed, still flutters. New mainsail has no leech flutter.
Any advice, do I keep on the sailmaker to do something or is it something I'm doing?
 
Jul 7, 2004
8,402
Hunter 30T Cheney, KS
I would have thought moving the car was the answer. I would go back to the sailmaker.
 

Ted

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Jan 26, 2005
1,254
C&C 110 Bay Shore, Long Island, NY
Most headsails will need a small amount of tension on the leech line to keep it from fluttering, even new ones. Having leech battens in a small headsail would certainly help but it's not appropriate in your situation since you have it on a roller furler. A good quality one year old sail shouldn't need excessive leech line tension in 12 knots of apparent wind unless it's been subjected to conditions it wasn't designed for. Using a sail in wind speeds which exceed the wind speed it was designed for will permanently damage the sail. If leech flutter was happening from day one I would keep after the sailmaker because leech flutter in a new sail is not normal. The longer the leech flutters, the more damage you are doing to the material and you could destroy a new sail within a season. What type of material is the sail made with? Was it a "name brand" or generic? All materials are not equal even if you compared identical weights of Dacron. Who was the manufacturer?
 
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Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Car father forward?

But the probable cause is that the jib's luff does not have enough hollow.

Headsails are cut with negative roach (hollow) so the leach does not flutter. Jibs are allowed to have less, and often the sailmaker cuts it too flat and flutter occurs. I would ask your sailmaker to recut the leach, or add vertical battens. He knows bettter. This is a common problem.

This jib would flutter with this much roach without battens.

 
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Feb 26, 2004
22,760
Catalina 34 224 Maple Bay, BC, Canada
Jack's right.

Has your sailmaker gone out on your boat with you to see it "in action?"

If not, he should.
 
Jan 22, 2008
763
Hunter 340 Baytown TX
It is a name brand sail with a local loft. And the sailmaker has gone out on the boat and seen the flutter. He just pulled the leech line in real tight and said don't worry about the windward cup. I thought the trailing edge was very important and a "cupped" leech would cause turbulence right where the "slot effect" of the two sails actually increased lift.
 
Jul 14, 2015
840
Catalina 30 Stillhouse Hollow Marina
Sailmaker is wrong. My 135 is 8 years old and no flutter in any wind.
 
Oct 3, 2011
825
Anam Cara Catalina 310 Hull #155 155 Lake Erie/Catawba Island
Whenever we have a question or concern about our sails our sailmaker-Al Declerq-North Sails Detroit has me send him photos and has been out with us to address an issue. We even sent a sail back to be re-cut at no extra charge. When you buy sails and spend that much money on a product, I want service not lip service.
Its about customer service. I am guessing it maybe car position.
 
Jul 7, 2004
8,402
Hunter 30T Cheney, KS
The OP said he has tried the cars in every position. The sailmaker just said to tighten the leech and call 'er good.
 
Jan 22, 2008
763
Hunter 340 Baytown TX
The OP said he has tried the cars in every position. The sailmaker just said to tighten the leech and call 'er good.
Justin, you summed it up pretty good. I had hoped buying new sails was going to be a better experience than it's been. The new mainsail seems to have good shape and performance, but it's a foot too short. When I point that out, it's met with silence from the sailmaker.

IMG_1871.JPG


I'm going to try to get some action from the sailmaker again, in a couple weeks when the latest race series is over.
I have a code 3 on order from a different loft, a local company that makes the sails onsite. Hope it turns out to be a better experience.
 
Jun 29, 2010
1,287
Beneteau First 235 Lake Minnetonka, MN
I had the same problem with my 135 on my boat. @Jackdaw and I talked about it over beers cause, that's how things get done and he sailed on my boat. Said it needed more hollow. Sent it back and had the sail maker fix it. All good now. Shouldn't cost you anything either. I did pay to ship it out to the sail maker.
 
Feb 26, 2004
22,760
Catalina 34 224 Maple Bay, BC, Canada
I had hoped buying new sails was going to be a better experience than it's been. The new mainsail seems to have good shape and performance, but it's a foot too short. When I point that out, it's met with silence from the sailmaker.
Bill, really sorry to hear this, I feel for ya.

But c'mon, would you put up with that nonsense in anything else in your life?

So, you buy a computer with W10, X speed processor and Y gigs of RAM and find, when you start it up, you have Windows 3.1, a slower processor and a lot less RAM.

What would you do? Stick with it and suck it up, or return it immediately and get what you paid for?

A foot too short? Whew...:yikes::yikes::yikes:
 
Jul 7, 2004
8,402
Hunter 30T Cheney, KS
I agree with Stu. If the sailmaker won't make good, take him to small claims court
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
First a question about your 'sailmaker'.

Is he a sailmaker who measures, designs, cuts and sews that sail?
Or his he a sailmaker who gets numbers and sends the deata off to a Asian loft and then delivers the sail.

The first guy would readily fix that problem, the second has more of a problem.

The main should be an easy call. Who measured the sail for the worksheet... you or him? Measure the luff against the worksheet, that will tell you who's on the hook for that. That sail is WAY short. More than a foot.
 
Jan 22, 2008
763
Hunter 340 Baytown TX
First a question about your 'sailmaker'.

Is he a sailmaker who measures, designs, cuts and sews that sail?
Or his he a sailmaker who gets numbers and sends the deata off to a Asian loft and then delivers the sail.

The first guy would readily fix that problem, the second has more of a problem.

The main should be an easy call. Who measured the sail for the worksheet... you or him? Measure the luff against the worksheet, that will tell you who's on the hook for that. That sail is WAY short. More than a foot.
It is one of the very large worldwide sailmakers with a local loft. I told them I wanted replacement sails for my boat, the mainsail to be 2 full battens, 2 partial, and 2 reefs. Just like the original. They did the rest, I gave them no measurements and they recommended the Dacron weight. I'm sure they were made on some other continent.
Since all the replies to this thread have reinforced my opinion that the leech flutter is due to defects in the jib cut or design, and should not be there, I have contacted the sailmaker. He will get with me in a couple weeks and see what they can do. I'll update how things turn out with both sails.
Thanks everyone for the advice and opinions.
 
Oct 3, 2011
75
Tayana 52 Jax
I believe that some Sunbrella material tends to shrink. If you have Sunbrella or similar sun protection on your jib could this be pulling the sail out of shape?
 

meb135

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Nov 17, 2012
92
Hunter 33 Shediac Bay
My new jib with a sunbrella UV protector does the same thing when the wind gets to around 15k apparent and I'm only having this problem on port tack. I've tried all the setting adjustment with no effect (mast is straight). Tightening the leech line is the only solution.
To me it does look like the wind is catching the edge of the UV protector when on port tack but some of you are suggesting there may be another cause. Calling the sailmaker is on my to do list.
 
Jan 22, 2008
763
Hunter 340 Baytown TX
That was one reason the sailmaker gave for the flutter, that dacron and sunbrella stretch at different proportions. But the sail is pretty new and I have been looking at every other boat I get the chance to, and not many have leech flutter at all, let alone as bad as what I'm getting. And they almost all have a sunbrella UV strip cover.
 

Pat

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Jun 7, 2004
1,250
Oday 272LE Ninnescah Yacht Club, Wichita, Ks.
great photograph!....Tells a story. Pat