Mainsail Sailcloth Weight - 8, 9, 10oz ?

[Bash]

Originally Posted by SvenG

Curious why you chose a lose foot for cruising ?

Not saying you shouldn't.



-SAven

SAven, I'm a huge fan of loose-footed mains. They offer many more shape options when sailing off the wind, especially in light air. You can put a lot more belly into a loose-footed main than a shelfed sail. And a loose-footed main is far more responsive to outhaul trim.

The more you sail downwind, the more a loose-footed main makes sense.

[Jon Hacking]

We're a (heavy) 45' cat (specs here). Our fully battened 750sq ft main is 10 years old & has worked well for us for 36,000 miles. It's nominally 9oz cloth but doubled on the leech, which covers well over half the sail area. It's still in OK condition (no tears or serious repairs) but I'm noticing that the leech is a bit stretched, despite the doubled cloth. This only affects our upwind performance, which (being gentle-folk) we never get a chance to test

Folks have talked about different sail cloths. We want long life, so don't want a laminate. But I've heard of a Dacron cloth that has Spectra (Dyneema, whatever) threads sown in every 1/4" or so, sort of like a rip-stop nylon.

Is this what Vectran is, that Bash mentioned earlier? I would think this would help the sail keep it's shape without the problems of laminates. I'd also think it wouldn't cost much more than Dacron.


But sailmakers keep pushing us away from it.

• Does anyone have any real experience with this sort of sail-cloth?
• How much more does it cost over a good Dacron sail?
• How long does it last?
• Does it still stretch?
• What are the positives & negatives?

Any info much appreciated! Thanks!

[matauwhi]

G'day, mates. We went back & forth, when buying our new main a couple of years ago on the loose foot option. Went with the loose foot, with absolutely no regrets. We have not given up any upwind performance. Cheers.

[SaucySailoress]

Hadn't thought about the rain catchment.

My feelings are your main should be as heavy and durable as possible. As should your primary genoa. I think you'll find you appreciate the value of a heavy sail in heavy weather when the poop hits the deck...

If you want lightweight sails for racing or wotnot, then get a light genny.

We have a furling genoa, so it is heavy. Because it's now on a furler, we no longer have the option of changing to the no.1 light in any sort of hurry. So, if wnids are light, we simply stick the spinnaker up - which works until the wind is at about 60degrees in light airs - less in heavier airs - but then the genny comes back out anyway.

[akio.kanemoto]

Wow, thanks for all the replies.

So in the replies, there were several responses hinting at heavier than 9oz.

While I'm not "planning" on hard passages - any passage can turn into a "hard" passage given the wrong time and place (or lack of knowledge!) - I'm essentially a big chicken with little experience, so I'm deliriously more than happy to spend the extra money on heavier cloth if it's going to help my safety and comfort and/or make life easier in some way.

Any more votes for 10oz? Or upgrade to and just stick with 9?

[Joli]

Your boat will have a high leech load which will necessitate a very heavy Dacron or a very strong laminate.

We've used two ply Dacron jibs and while they are strong they do stretch, we may as well remove the luff tape and sew it to the leech after a while. We did blow up a two ply 20 oz jib last year and have replaced it with a carbon/kevlar laminate that weighs half as much and holds its shape much better. Our main is a spectra laminate ~13 oz. and while getting long in the tooth it still has good shape and seems to be going strong. It's 15 years old now with ~20k miles?

For your main, to save the weight and keep a decent shape I would consider a laminate. Dacron may live longer but the shape will quickly become crap. I can't sail that way.

Originally Posted by Jon Hacking

We're a (heavy) 45' cat (specs here). Our fully battened 750sq ft main is 10 years old & has worked well for us for 36,000 miles. It's nominally 9oz cloth but doubled on the leech, which covers well over half the sail area. It's still in OK condition (no tears or serious repairs) but I'm noticing that the leech is a bit stretched, despite the doubled cloth. This only affects our upwind performance, which (being gentle-folk) we never get a chance to test

Folks have talked about different sail cloths. We want long life, so don't want a laminate. But I've heard of a Dacron cloth that has Spectra (Dyneema, whatever) threads sown in every 1/4" or so, sort of like a rip-stop nylon.

Is this what Vectran is, that Bash mentioned earlier? I would think this would help the sail keep it's shape without the problems of laminates. I'd also think it wouldn't cost much more than Dacron.



But sailmakers keep pushing us away from it.

• Does anyone have any real experience with this sort of sail-cloth?
• How much more does it cost over a good Dacron sail?
• How long does it last?
• Does it still stretch?
• What are the positives & negatives?

Any info much appreciated! Thanks!

[estarzinger]

Originally Posted by Jon Hacking

Folks have talked about different sail cloths. We want long life, so don't want a laminate. But I've heard of a Dacron cloth that has Spectra (Dyneema, whatever) threads sown in every 1/4" or so, sort of like a rip-stop nylon.

That's Dimension-Polyant's Hydra-net. They have two types - regular/square/crosscut and radial. The regular style is a rip-off (IMHO), with not enough spectra content to make any difference and it tests no better than a plain high quality Dacron cloth the same weight. The radial is apparently a better cloth, but fabric will stretch on the bias (45 degrees across the weave) just like a plain Dacron cloth and so to use it properly you have to make the sail in tri-radial construction (rather than cross-cut) which makes the end sail rather more expensive (tri-radial cutting wastes about 20-30% of the sail fabric).

Originally Posted by Jon Hacking

Is this what Vectran is, that Bash mentioned earlier? I would think this would help the sail keep it's shape without the problems of laminates. I'd also think it wouldn't cost much more than Dacron.

No, that's Hood's 'Vektran' cloth. Its a very nice woven Dacron with a few (very few) threads of vectran pulled thru. The test results and real world experience suggests the vectran does nothing at all for the cloth - just there for marketing purposes. But it is a very nice woven Dacron. Hood has some very old fashion looms that are too slow by modern standards but produce an excellent tight weave.

Originally Posted by Jon Hacking

• Does anyone have any real experience with this sort of sail-cloth?
• How much more does it cost over a good Dacron sail?
• How long does it last?
• Does it still stretch?
• What are the positives & negatives?

The only one worth considering is the DP radian hydranet - the others are just marketing. So compared to a good Dacron sail, the cloth will be lets say 20% more and then because it has to be radial construction you will need about 20-30% more cloth, so lets say cost 40-50% more in total.

This sail will have a lot less stretch (than Dacron) in the zero direction, which is the only direction the spectra fibers run, but will have the same stretch in the bias (45 degrees) and 90 degree directions. This is called an unbalanced cloth (much stronger in one direction than the other) and it created a challenge for the sail designers - if you downsize the weight to take advantage of the higher 0 direction strength you then have a sail that might easily blow out at the reef points or anywhere there are loads off the primary axis. This can be handled with careful design, but requires some experience on the part of the sail designer.

It will last about as long as a good Dacron sail, perhaps 30-50% longer than a laminate.

[S/V Alchemy]

Originally Posted by akio.kanemoto

Any more votes for 10oz? Or upgrade to and just stick with 9?

I think opting for the 9 but looking for the doubled Dacron at the leech and reinforcement patches/triple stitching gives you the best of both worlds.

One other comment I would make is that you consider a light main, either one you already own or a used one that's a reasonable if not an exact fit. One point is that this will work better in periods (one or two days) of light airs, and when combined with a spinnaker and with preventers rigged, you can "drift at speed" even in five-six knots of wind. Me, I would be fine with a 72NM 24 hour run at three knots if it was steady and the seas were relatively flat. I'd rather keep the dozen gallons of diesel in the tank for either a dead calm or getting through a lagoon entrance, personally. A light main gives you these advantages, and, of course, is a potential spare when you have to sew up a seam on the heavy one in the calm after the storm.

[S/V Alchemy]

Originally Posted by estarzinger

It will last about as long as a good Dacron sail, perhaps 30-50% longer than a laminate.

Interesting perspective, Evans. You seem to find a place for performance in distance cruising over the "bulletproofness" associated with heavy Dacron, which even if it takes a part-gale to move the boat, can in fact take a part-gale without parting.

Two questions:

1) If you were to comment on a particular all-Dacron sail for a 40 footer, say with a 14 foot boom (pretty typical), which weight, cut and maker would you suggest?

2) What have been your experiences with reef points on a Dacron/Vectran "mixed" main sail cut in patterns other than cross-cut? You mentioned the need to account for differing patterns of strain; have you encountered this on such sails? Are there special care and usage requirements for such a main when compared to the relatively straight-forward jiffy or slab reefing of a reinforced, 9 or 10 oz cross-cut Dacron?

Thanks.

[delmarrey]

Originally Posted by Saucy Sailoress

Hadn't thought about the rain catchment.

It can be done with a loose foot also. Just leave the outhaul tight and reef the sail down a couple inches, Which puts a belly in the foot. If the sail is still performing (underway) then one can tie down the first mast slider around the gooseneck and tighten up the luff.

But I prefer a water maker. I've never had much luck catching rain underway, only at anchor.

[Bash]

Don't get sucked into the trap that if 9oz is good, 10oz must be better. A 10oz sail is a bear to work with, and you'll start losing significant performance with it. On a boat your size, 8oz dacron is ideal. You've been advised to kick it up to 9oz because of your plans to circumnavigate. That was good advice, given your preference to stick with straight dacron. (For my part, I'd have gone with a reinforced dacron and stayed with 8oz, but performance is probably more important to me than to most cruisers.)

You won't enjoy sailing a 10oz sail, especially in light air. With full battens, you won't even be able to see when it begins to luff. On the other end of the wind spectrum, tucking in a reef will be a major battle.

Bottom line is that your main isn't big enough to demand that heavy a fabric.

[estarzinger]

Originally Posted by S/V Alchemy

Interesting perspective, Evans. You seem to find a place for performance in distance cruising over the "bulletproofness" associated with heavy Dacron, which even if it takes a part-gale to move the boat, can in fact take a part-gale without parting.

I like to be able to sail upwind. You need decent shape to be able to do that (effectively). So, while a Dacron sail will last as an intact white triangle for say 40,000 miles, it will only be an effective upwind sail for perhaps 25,000 (these are very general estimates which depend a lot of the particular usage circumstances). For us, laminate sails tend to last around 25,000 miles and then the Mylar (the film goes first, not the load carrying fibers) starts to get weak enough to give me concern. So, for us the effective life is actually quite close between the two, but I am much more picky about sail shape and upwind performance than most.

Originally Posted by S/V Alchemy

1) If you were to comment on a particular all-Dacron sail for a 40 footer, say with a 14 foot boom (pretty typical), which weight, cut and maker would you suggest?

I am not an expert on this, nor do I have data on all the available Dacron options, but given what I know for plain Dacron I would be very tempted by a 9oz hood. As I said above, hood is using some old looms that are slow but weave tighter than the bigger guys. Unfortunately, Hood have been lousy at running their business and have almost disappeared.For a slightly higher performance I would be tempted by a DP hydranet radial (their hn383 for a 40'er) - any loft can buy this cloth.

Almost all the dacron cloth comes from either DP or Challenge, and they both make fine cloth. There two exceptions I am aware of - Hood makes their own, and North has some proprietary dacron cloth which I believe they don't make but subcontract out.

Originally Posted by S/V Alchemy

2) What have been your experiences with reef points on a Dacron/Vectran "mixed" main sail cut in patterns other than cross-cut? You mentioned the need to account for differing patterns of strain; have you encountered this on such sails? Are there special care and usage requirements for such a main when compared to the relatively straight-forward jiffy or slab reefing of a reinforced, 9 or 10 oz cross-cut Dacron?

The only dacron/vectran mix cloth I am aware of is the Hood, and the vectran does almost nothing and the cloth is actually quite 'balanced' (according to the test results I have seen), so that cloth can be made into a cross cut sail just like conventional dacron without worrying in the sail design about unbalanced cloth properties.

On the other hand, the DP hydranet radial, which is a dacron/dyneema mix, is very unbalanced and the sail design does need to take that into account. I have seen several of these sails when they were new but I have not seen one after say 30,000miles, so I can't really make an assessment of how different designs have held their shape. For several sails with that sort of miles, I have been told 'their shape is as good as new', but that simply tells me the owner is either not very knowledgeable or sensitive to shape, as even the best high modulus laminates change shape after that much use and UV.

[S/V Alchemy]

Thanks, Evans. I am coming to the point where I will be ordering the "passagemaking main" and as it's a steel boat with a relatively stumpy (if long-boomed) main, I need to balance several aspects. I know I'll be leaving up a full hoist at higher wind speeds than most, but after that, it's a wide open proposition.

[estarzinger]

Originally Posted by S/V Alchemy

Thanks, Evans. I am coming to the point where I will be ordering the "passagemaking main" and as it's a steel boat with a relatively stumpy (if long-boomed) main, I need to balance several aspects. I know I'll be leaving up a full hoist at higher wind speeds than most, but after that, it's a wide open proposition.

Its been my experience with a cruising dacron main that the stitching starts to go well belore the cloth - so just to add some complication to your life - I would focus as much (or more) attention on the stitching - thread type & denier, single/double/triple stitched, etc.

actually this is true of laminate triradials also - the stitching started to go on my last spectra laminate main and the sailmaker and I concluded they has somehow used one denier size too small on the thread.

[barnakiel]

Originally Posted by estarzinger

Its been my experience with a cruising dacron main that the stitching starts to go well belore the cloth - so just to add some complication to your life - I would focus as much (or more) attention on the stitching - thread type & denier, single/double/triple stitched, etc.

actually this is true of laminate triradials also - the stitching started to go on my last spectra laminate main and the sailmaker and I concluded they has somehow used one denier size too small on the thread.

The sailmaker will use the thread according to the weight of the cloth. Also, for a cruising sail the stiching will be triple and very often a three-step, not zig-zag, where applicable. Some tapes will be stiched twice too - if the have the staggered design. These things develop and change as new ideas, new equipment and new materials enter the loft but this was the status some 5 years ago. A good sailmaker follows such developments and applies them as applicable. This is one of the benefit of using a big loft - they are usually the first to apply such newer techniques as they have plenty of experience trickling down from their racing portfolio.

If you ask your sailmaker and if your sailmaker has daily contact with the cruising crowd they WILL add some nice touches - e.g. coloured thread, oversize reef patches, etc.. Our sailmaker always specifies 3 reefs for a cruising boat and super duper leech-line cleats backed by grommets. From my sailing experience I can say they are right.

Some form of extra chafe protection goes a long way for a cruising sail - e.g. at the spreaders level (for each reefing position) and at stanchions for geenoa - if the sail sweeps the stanchions. The same applies to the quality and execution of the UV patch on the genoa - there are many ways to do it and some are better than others.

b.