Experiences with Load Path Sails ?

[Dockhead]

My sails are original to the boat - so 10 years old. They are in pretty good condition, as the boat was lightly used prior to my ownership (my pattern of use is different!!). They are less baggy than other boats in my charter and ownership over the years, and my boat sails pretty well.

HOWEVER, I do have a problem with chronic weather helm. I have tried every trick in my book (maybe there are others*), but I still can't get the sails balanced very well when the wind is up a bit and gusting. My last Channel crossing (my 10th) was really tough -- with winds gusting 23 -- 25, the boat really wanted to round up, ripping the wheel out of my hands, unless I reefed down so far that I was seriously losing drive at the normal wind speed of 18 or so.

I'm starting to think that my mainsail is just baggy enough to prevent me from trimming it flat enough to deal with that situation. So I start to think about new sails. Maybe this is a good excuse!

I have my eye on load-path sails like the Dimension-Polyant D4 sails. They are cheaper than laminate and are supposed to be nearly as durable as Dacron. Plus they are lighter. They roll up tighter which should make them good for my furling main system. What's not to love? They are supposed to be more vulnerable to chafing, by my rig does not subject the sails to much chafing. Any real experience on here?


* My anti-weather helm tricks: (a) traveller down; (b) reef the main earlier than the jib; (c) slack mainsheet a little (unless hard on the wind), put on vang; (d) more outhaul tension to flatten the mainsail; (e) more halyard tension on the main; (f) trim the jib to move the draft forward. Anybody have any more?

[Rick01541]

Look at the rake of your mast. If the rake is too far aft you will have excessive helm. I moved the base of my keel stepped mast one half inch aft which moved the rake forward and balanced my helm beautifully. Of course you will need to shorten the forestay to compensate.

[estarzinger]

Originally Posted by Dockhead

They are cheaper than laminate and are supposed to be nearly as durable as Dacron. Plus they are lighter. They roll up tighter which should make them good for my furling main system. What's not to love? They are supposed to be more vulnerable to chafing, by my rig does not subject the sails to much chafing. Any real experience on here?

Yes, we have had two load path jibs and one main. Whoever told you they are nearly as durable as Dacron is fibbing. Their durability is pretty much just like laminate sail. The Mylar goes first. We have never had the load path fibers break. We get about 25,000 miles from a load path and 40,000 from Dacron.

The sails do also change shape over time but in a different way that dacron. The mylar shrinks while the leach blows out and you develop funny pockets around any reinforcing (like the reef points). It still looks way better than a similar age dacron sail but don't let anyone tell you they hold their shape for their life. We loose about 3 - 5 degrees of pointing ability over the life of a load path jib as the shape goes.

I do agree that he starting shape and light weight and smaller roll of the load path's are very nice.

But I doubt it is THE solution to your helm problem. Quite honestly and sorry to say this, it sounds like you have either an unbalanced hull (it changes its 'in the water footprint' when it heels) or a rudder problem, or you are simply sailing with too much canvas up - how much were you reefed in the 23-25 kts you mentioned?

[Dockhead]

Originally Posted by estarzinger

Yes, we have had two load path jibs and one main. Whoever told you they are nearly as durable as Dacron is fibbing. Their durability is pretty much just like laminate sail. The Mylar goes first. We have never had the load path fibers break. We get about 25,000 miles from a load path and 40,000 from Dacron.

The sails do also change shape over time but in a different way that dacron. The mylar shrinks while the leach blows out and you develop funny pockets around any reinforcing (like the reef points). It still looks way better than a similar age dacron sail but don't let anyone tell you they hold their shape for their life. We loose about 3 - 5 degrees of pointing ability over the life of a load path jib as the shape goes.

I do agree that he starting shape and light weight and smaller roll of the load path's are very nice.

But I doubt it is THE solution to your helm problem. Quite honestly and sorry to say this, it sounds like you have either an unbalanced hull (it changes its 'in the water footprint' when it heels) or a rudder problem, or you are simply sailing with too much canvas up - how much were you reefed in the 23-25 kts you mentioned?

Well, 25,000 miles doesn't sound too bad -- considering they are cheaper than laminate. But you didn't say -- altogether, do you like them? Are you happy with them? So the shape changed -- was it mostly good? Better than Dacron? Did you get a big performance boost?

As the unbalanced hull -- I hope not. She was designed by a great designer, and not that long ago, so I would hope decent balance is designed in. In the incident I mentioned, the main was reefed down fairly deeply -- to the third spreader, which would have reduced the area by probably 30%. The yankee jib was reefed to the first reef mark on the sail. Any less sail up, and we would have been going slow between gusts. Although I don't exclude that this is just the nature of sailing in gusty conditions.

I don't usually need to reef at all up to 20 knots or so, even hard on the wind. I reefed more than usual to try to control the weather helm problem, alas, without success.

[estarzinger]

Originally Posted by Dockhead

do you like them? Are you happy with them? So the shape changed -- was it mostly good? Better than Dacron? Did you get a big performance boost?

Yes, terrific sails. When new the three things you notice are that (a) there are no lumps or bumps or seam lines - just a smooth flowing perfect sail shape; and (b) that the sail shape is good even if you suck at sail trim - they just seem to fall into the right shape, and (c) the shape stays good right thru the gusts.

As to a "big performance boost", for sure better upwind especially in gusty conditions, but generally on other points of sail no.

As the unbalanced hull -- I hope not.

Is there a sistership's owner you could ply with some single malt and see how his hull performs in similar conditions? And/or take a rigger and sailmaker out for a sail (you will need a similarly windy day) and have them fiddle with things and see if they can make a difference. With a dacron sail you can usually pull/stretch it into moderately acceptable shape unless its totally dead.

New sails can only help and at 10 years you are about due in any case. Ask the sailmaker to make the main bit flatter. But I really doubt this is the primary cause of the problem.

There are lots of modern hulls that become very hard mouthed when you get those sort of 25kt gusts. Its sometimes the price for all that beam and big transom and its interior volume. if its one of those hulls, the best you can do is push the sail area center of effort as far foward as possible - lots of jib and not much mainsail.

.....

[Dockhead]

Originally Posted by estarzinger

....There are lots of modern hulls that become very hard mouthed when you get those sort of 25kt gusts. Its sometimes the price for all that beam and big transom and its interior volume. if its one of those hulls, the best you can do is push the sail area center of effort as far foward as possible - lots of jib and not much mainsail.
.

Well, my boat is a Bill Dixon designed Moody 54, and the hull form is not dictated by interior volume and is very different from current production boat fashion -- the beam is not wide -- 16 feet for 46 feet of waterline and 54 feet LOA. And the transom is not wide. Nor are either the aft sections nor forefoot flat as in many modern production boats. It's a performance oriented bulb keel hull with semi-balanced rudder. I would not expect the hull shape to be the problem.

More likely is that my sail trimming skills suck to such an extent that I have been unable to pull the mainsail into shape -- that is, flat enough for those conditions. I'll keep trying.

Meanwhile I am eyeing those load path sails. I like very much what you say about them -- that sounds good. Of course, upwind performance is what it's all about. Any old rag will work downwind where you don't need any aerodynamic lift.

[Bash]

If those are OEM sails that came with the boat, you've probably gotten all you'll get out of them unless you want to try a recut. The dacron in most OEM sails is not the highest quality cloth, and I think you're wise to suspect that this is where your weather helm is coming from.

When I got to that point on my last boat, I had a tri-radial main built of a cruising laminate that had a dacron scrim. Vertical battens. It was unbelievable how much difference that sail made in terms of weather helm and pointing ability, even in comparison to how the OEM sail worked when it was brand new.

[gjorgensen]

We're currently on our 3rd generation of load path racing sails over the 10 years we've owned our 40.7 (UK Tapedrive, UK Ultra, and now Quantum Fusion M). I also have a lot of experience both racing and cruising with Dacron sails, and some experience with both 3DL and 3Di.

I'd echo a lot of what was said above, especially Evans' comments. Most load path sails use a base cloth that's a laminate of mylar and some other material (dacron, vectran, spectra, kevlar, carbon). Depending on the construction, the load path fibers may be laminated between the mylar, or glued to the outside. Either way, the mylar is the weak link in the sail. Mylar shrinks and turns brittle with age, even in the bag. Both UV and heat will speed that along, but it'll happen regardless. My experience has been that at about 4 years you'll see the mylar start to crack, and by the 5 year point you'll see significant amounts of mylar failure, in the form of delamination and/or outright breakage. A common site on racing sails at that age is for them to turn to cheese cloth - whole sections of mylar will blow out, leaving the high tech load path threads simply hanging there. The mylar will also not tolerate flogging nearly as well as dacron. If you frequently flog the main (e.g. motor with no wind), the mylar will start to fail prematurely, typically along the leach, again by simply breaking out. A dacron protective layer over the sail can help these problems a little, but you'll never get the mechanical longevity you'll see from dacron.

That said, the load path sail will hold a good shape longer than dacron, depending of course a lot on how the dacron sail was constructed. The typical age issue I've seen with dacron is the common "blown out" shape, where they get a deep belly, often worse up high. The result is exactly the problem you're describing - no pointing ability, and little ability to flatten the sail to depower it. That's probably leading to your round ups. As Evans says, load path sails age differently, with the point of maximum draft moving aft (which hurts pointing), severe leach hook, and a lumpy shape as the mylar shrinks unevenly. You'll really see that with something like a UK Tapedrive sail, where the tapes are glued onto the outside of the sail, and have radically different shrink characteristics than the cloth they're taped to. I'm not sure if Doyle's load path sails are constructed the same way or not. One good thing is that I've never seen a laminated sail get a deep belly, probably because they don't really stretch (or maybe because they fall apart before then).

A couple other points to help in the short term. Your description of your trimming actually sounds good - tight halyard and outhaul, vang-sheet to induce twist and dump air from the top of the sail, and play the traveler. As Rick says above, make sure you're not carrying a bunch of rake in the rig - it should be standing close to straight up with the backstay relaxed. Also, be sure you don't have a bunch of sag in the forestay, which will induce weather helm - for heavy air you'll want the headstay tight. If your backstay is adjustable, crank on the backstay to induce rig bend (not rake). That will make a huge difference on a blown out sail. This is our primary weapon across wind speed, and you use progressively more in heavy conditions as the sail ages. Also, I believe your boat has swept spreaders. You can put some pre-bend in the rig with more tension on the cap shrouds, which will help even if your backstay is not adjustable.

Last, check the tension on your diagonal shrouds. You have a three spreader rig, so you have 3 sets of diagonals. The lowers don't matter that much, but be sure you have good tension on the middle and upper diagonals. Loose tension on them will allow the rig to sag in the middle, which will make the main deeper as the wind comes up, inducing weather helm. If you're not very certain how the rig on your boat should be tuned I'd pay a sail maker to do this for you, and make sure he looks at it while sailing in ~15 knots of wind. The rig should probably still be about straight in that wind speed, so the middle and upper diagonals should probably be tuned for that. If you still have issues after all this is done you're probably down to needing a new mainsail which, at 10 years old, is probably pretty likely anyway.

[estarzinger]

Originally Posted by gjorgensen

3Di.

.

What sort of 3di have you sailed with? and what's your reaction as potential cruising sails?

I was talking with them about a set of high spectra content 3di, for cruising, but got cold feet after talking with one (the only one I think) of their cruising 3di references - there was some adhesive failure going on.

[gjorgensen]

Originally Posted by estarzinger

What sort of 3di have you sailed with? and what's your reaction as potential cruising sails?

I was talking with them about a set of high spectra content 3di, for cruising, but got cold feet after talking with one (the only one I think) of their cruising 3di references - there was some adhesive failure going on.

The one I sailed with was the main on a sister Beneteau 40.7 here in San Diego in 2009. This was one of the early 3Di sails right after they came to market, so things may have changed. Also, this was a pure racing sail, made of carbon and spectra. That said, the 40.7 has a much smaller main than Hawk, yet this sail was almost unmanageable even with a full racing crew, on a beer can race with almost no wind.

Delamination would be a major worry of mine, although oddly maybe not the biggest. The sail's construction is similar to the way you'd lay up fiberglass or carbon - basically strips of material glued together in layers. From what I understand there's basically no pressure used on the cloth during layup, so the adhesive has to be either heat/UV activated or simply an air dry. It works, but I'd be worried that a panel somewhere would start to lift due to insufficient activation of the adhesive or inadequate wet-out. I don't know that one lifting would be prone to spread though. There are no seams, so once a tear or hole starts the sail would be subject to simply "break" all the way across. On the other hand, it's similar to cuben fiber, which has proven very durable on the offshore race circuit.

Outside of that, I was stunned at how hard the sail was to handle. There's no doubt these sails do not stretch. At all. None. It's like sailing a sheet of steel. It holds its shape incredibly well. On the other hand, the lack of stretch transfers all the shock loads into the rig, rigging, and hull. It also prevents the sail from adapting to rig changes as well in my opinion. The sail looked beautiful in the default rig settings, but the lack of stretch made it bend funny when we put on a bunch of backstay or loosen the halyard. That alone would prevent me from wanting one on a cruising boat unless they built it out of something that would stretch a bit more and provide some shock buffering.

His 3Di was incredibly stiff, so much so that simply dropping and flaking the main was a major event for 6 of us in basically no wind. The stiffness translated into a large bend radius, so even getting it to feed up and down the mast past the boom was a major trick. Flaking it was a nightmare - it didn't want to bend, and each flake must have been 2.5 feet in diameter. It was bulky and didn't want to stay flaked. The owner had never reefed it, and was not sure he actually could because of the difficulty bending it. The material did not tolerate crinkling or bending at all. If you tried to fold it hard you'd create a permanent crease. If you crinkled it up, it was like crinkling a piece of paper - when you straightened it back out, there were permanent creases left in the sail.

If you ask me, his sail was completely unsuitable for a cruising sail, and in fact was really an unpleasant sail to deal with when club racing. Now, it's entirely possible that a cruising version would be made of something a little stretchier. But even so, I believe the adhesive and build are partly responsible for the stiffness and problems with bending and creasing, so even a cruising sail may suffer from those problems. I couldn't imagine trying to use a sail like this double handed, throwing reefs in and out frequently, and often using it to roll downwind across oceans. If you want another laminate sail, I'd go with something more conventional, either 3DL or a load path sail. I was in the market for a new main at the same time and bought a Quantum Fusion M instead that I've been delighted with.

[barnakiel]

Great sails. More expensive than the regular stuff.

Chances of delamination must be considered.

b.