Got a new main, and got to try it out last Sunday in 15 to 20 knots. The first thing I noticed was that even though we had the halyard cranked quite tight, with the headboard up as far as possible, we still had slight scallops in the luff. I just couldn't get the luff taught. Then as we went on a beam reach, a new boat sound appeared. Sounded like baseball cards in the spokes of a Stingray bike. Looking high and low, I finally noticed the luff of the main was vibrating like crazy. Still in discussions with the sailmaker about the luff length, but he says the motorboating luff is something "some boats do on a beam reach." I've never seen this before in a main luff. Anyone else had this expirience? Any suggestions/advice? Sounds like dollar bills are fluttering off my new sail. Thanks, Brad
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H
hp
It happens
Particularly in a big wind or a gust. You can tighten the leech line but that will make the main scallop. Not to worry, the effect is not prolonged, so there's not much risk of damage.
Particularly in a big wind or a gust. You can tighten the leech line but that will make the main scallop. Not to worry, the effect is not prolonged, so there's not much risk of damage.
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Mike
I don't know about that. I have never experienced that before in the mainsails I have had. I would try to tighten the downhaul or cunningham and see if it goes away. I would also measure the luff and compare it to your boat. It might be slightly too long. The luff should be shorter than the dimension of the boom to the mast head (minus the halyard shackle). If it is the sailmaker would probably fix it for you. Good luck.
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Al
luffing
sounds like the luff length is incorrect. in time the sail will stretch and it will get worse. sounds like a job for a downhaul. maybe the sailmaker should go out with you to see first hand the problem
sounds like the luff length is incorrect. in time the sail will stretch and it will get worse. sounds like a job for a downhaul. maybe the sailmaker should go out with you to see first hand the problem
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John Visser
Lower the boom!
On both the sailmaker and the boat! I think the luff is too long. This will have a seriously negative effect on performance. Can you take a look at the mast head with binoculars to see if the halyard is at maximum height? Can you pull in a reef and tight the luff enough to take out the scallops?
On both the sailmaker and the boat! I think the luff is too long. This will have a seriously negative effect on performance. Can you take a look at the mast head with binoculars to see if the halyard is at maximum height? Can you pull in a reef and tight the luff enough to take out the scallops?
J
Jose Venegas
I have a theory
I heard the same noise during the sea trial of my new Beneteay 361 a year ago. It was blowing about 20 and the halyard was very tight during a beam reach. The noise was exactly as you described. I mentioned it to the dealer but never got a good explanation. Initially, I reduced tension in the halyard during a beam reach to eliminate the noise but left some scallops. After time, the noise went away even with a tight halyard. My theory is that the line inside the luff was initially too short relative to the sail cloth. As a result, it had to be tensioned a lot to reduce sail cloth wrinkles although it could not eliminate them. This created the effect of a vibrating string that fluttered as the wind passed between the luff and the mast moving with it the slack sail cloth. I believe that as time went on, the luff line stretched and the effect went away. However, yesterday as I installed my North-cleaned sail before launching, I noted that the luff line shrunk during cleaning, and it is probable shorter than when the sail was new. I am worrying that the dreadful motorboat sound will come back, at least for a while. Due to bad weather I was not able to test the sail yesterday but I will report my finding as soon as I have a chance.
I heard the same noise during the sea trial of my new Beneteay 361 a year ago. It was blowing about 20 and the halyard was very tight during a beam reach. The noise was exactly as you described. I mentioned it to the dealer but never got a good explanation. Initially, I reduced tension in the halyard during a beam reach to eliminate the noise but left some scallops. After time, the noise went away even with a tight halyard. My theory is that the line inside the luff was initially too short relative to the sail cloth. As a result, it had to be tensioned a lot to reduce sail cloth wrinkles although it could not eliminate them. This created the effect of a vibrating string that fluttered as the wind passed between the luff and the mast moving with it the slack sail cloth. I believe that as time went on, the luff line stretched and the effect went away. However, yesterday as I installed my North-cleaned sail before launching, I noted that the luff line shrunk during cleaning, and it is probable shorter than when the sail was new. I am worrying that the dreadful motorboat sound will come back, at least for a while. Due to bad weather I was not able to test the sail yesterday but I will report my finding as soon as I have a chance.
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Todd Osborne
Cunningham
Tighten up the Luff from the bottom with a cunningham & see if that tightens her up. Also do a few tacks & see if the sail slugscars slide into proper position. Sometimes if you hoist a sail in high wind, the forces on the sail slugscars can keep them from properly positioning. You might put a little "McLube" on them to lube em' up. If after all that fails, You may have to re-visit your sailmaker to get satisfaction. Good luck!
Tighten up the Luff from the bottom with a cunningham & see if that tightens her up. Also do a few tacks & see if the sail slugscars slide into proper position. Sometimes if you hoist a sail in high wind, the forces on the sail slugscars can keep them from properly positioning. You might put a little "McLube" on them to lube em' up. If after all that fails, You may have to re-visit your sailmaker to get satisfaction. Good luck!
Cunningham and...
It definitely sounds like you need some more tension on the cunningham. Halyard tension alone should not be used to tension the luff, especially if your sail track has some friction in it, as you run the risk of ripping the top of the sail. The cunningham allows you to tension the lower half of the sail (where it really counts) without significantly increasing the load on the upper part of the sail. Also, in your search for friction in the mainsail hoist system, don't forget the upper sheave and check to make sure the knot on the main halyard shackle isn't wedged in the opening. Good luck. Peter H23 "Raven"
It definitely sounds like you need some more tension on the cunningham. Halyard tension alone should not be used to tension the luff, especially if your sail track has some friction in it, as you run the risk of ripping the top of the sail. The cunningham allows you to tension the lower half of the sail (where it really counts) without significantly increasing the load on the upper part of the sail. Also, in your search for friction in the mainsail hoist system, don't forget the upper sheave and check to make sure the knot on the main halyard shackle isn't wedged in the opening. Good luck. Peter H23 "Raven"
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Vic
Make the sailmaker fix it ...
you paid for a sail that works right ... don't need a cunningham ... that's just so you don't have to play with the main halyard all the time to reshape the sail. Actually the new sail should be a little short to allow for streching over the next year or so. Too Long is Bad ... The fix is to recut the base of the sail and they just don't like to do that. They will BS you into thinking you have to run the sail with a s curve in the base put there by the cunningham. And the other adjustments should take care of the motorboating ... by the way ... who is the sail maker? just so we know? Vic
you paid for a sail that works right ... don't need a cunningham ... that's just so you don't have to play with the main halyard all the time to reshape the sail. Actually the new sail should be a little short to allow for streching over the next year or so. Too Long is Bad ... The fix is to recut the base of the sail and they just don't like to do that. They will BS you into thinking you have to run the sail with a s curve in the base put there by the cunningham. And the other adjustments should take care of the motorboating ... by the way ... who is the sail maker? just so we know? Vic
B
Brad
Thanks all...
Great responses, and hopefully I'll get a chance to size things up again tomorrow. The weather here has been awful, but it's supposed to clear up. I'm going to check the slides and track, and spray on McLube, but I'm pretty sure the headboard was maxed. The binoculars suggestion might help make sure. Since the halyard shackle attaches at the rear of the headboard, there's quite an angle created between shackle and sheave up top, and it seemed any more tightening would only pull the headboard horizontally toward the mast. While I can see the value in the cunningham adjustment, I agree I should be able to get the luff firm with halyard alone, and as the sail stretches it'll only get worse. Interesting theory about easing to stop the motorboating...at 15 to 20kts with scallops, I kept trying to tighten. For now, I'm leaving the sailmaker's name out of it, cause he seems willing to work with me, even though he disagrees. I'll post it at the hopefully successful conclusion. My gut feel here is that the luff is too long, as most of you say, but in the face of the much experienced loft rep, I needed some backup. Thanks again all. Brad
Great responses, and hopefully I'll get a chance to size things up again tomorrow. The weather here has been awful, but it's supposed to clear up. I'm going to check the slides and track, and spray on McLube, but I'm pretty sure the headboard was maxed. The binoculars suggestion might help make sure. Since the halyard shackle attaches at the rear of the headboard, there's quite an angle created between shackle and sheave up top, and it seemed any more tightening would only pull the headboard horizontally toward the mast. While I can see the value in the cunningham adjustment, I agree I should be able to get the luff firm with halyard alone, and as the sail stretches it'll only get worse. Interesting theory about easing to stop the motorboating...at 15 to 20kts with scallops, I kept trying to tighten. For now, I'm leaving the sailmaker's name out of it, cause he seems willing to work with me, even though he disagrees. I'll post it at the hopefully successful conclusion. My gut feel here is that the luff is too long, as most of you say, but in the face of the much experienced loft rep, I needed some backup. Thanks again all. Brad
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Andy
A new sail on my old Tartan 30 did that
The new 2 + 2 main I had made for my old boat did the same thing. Luft length was correct. ONLY on a beam reach with the 17 kts of wind it would vibrate like a outboard motor. Tension had no effect on it. Changing sail trim wouild stop it but I'd loose speed. It only happened hull speed in perfect conditions. No answers, bought a bigger the boat. I believe the answer might have been in the webbing between the slugs and sail. ( too soft ). Air flow around the mast would hit the luft and vibrate it like a piece of grass between your thumbs.
The new 2 + 2 main I had made for my old boat did the same thing. Luft length was correct. ONLY on a beam reach with the 17 kts of wind it would vibrate like a outboard motor. Tension had no effect on it. Changing sail trim wouild stop it but I'd loose speed. It only happened hull speed in perfect conditions. No answers, bought a bigger the boat. I believe the answer might have been in the webbing between the slugs and sail. ( too soft ). Air flow around the mast would hit the luft and vibrate it like a piece of grass between your thumbs.
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