32-3 new main and sail track questions

Frank Langer

1984 Ericson 30+, Nanaimo, BC
Hi Frank,
Why do the tri-radial sails last longer? The question is kind of academic, as we ordered a crosscut main and tri-raidal jib. But I'm always interested in learning more.
Jeff
Hi Jeff,
I'm not a sail expert, but that seems to be a consensus among sail makers. As I understand it, because the tri radial sail is made with many small pieces of sail cloth, and seams and stitching are all in different directions, the stress on the sail cloth in a strong breeze is distributed more evenly and the stress resisted more effectively than in a cross cut sail where one long piece of sail cloth goes from the luff to the leach and has that whole length to stretch.
Others may have additional comments, but I don't think there is any doubt that a tri radial is superior to a cross cut sail. But if one only sails infrequently, or in light air, or is on a limited budget, a cross cut may be a reasonable option.
Frank
 

Christian Williams

E381 - Los Angeles
Senior Moderator
Blogs Author
Tri-rad probably holds its shape better but I doubt lasts longer. Service life depends more on weight of cloth and usage.

My lazyjacks are light Spectra, fixed to sides of boom (not under it), most-aft fastener position on boom dictated by longest full-length batten. Key is passive lines attached to spreaders about a foot out from mast. That spreads the lines a little for easier hoist (lazyjacks require boat headed accurately into wind on hoist, with some fiddling so battens don't foul.)

I spent five years with a slotted lazyjacks sail cover (56 snaps) and my new sail cover will not have slots. I'll tie away the lazyjacks before sail cover goes on. Those 56 snaps drove me bonkers, and flap-over slots in the cover allow rain water to run down the lines and penetrate to the sail.

lazyjack 1.JPG...3 lazy.JPG..slotted sail cover.JPG
 
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David Grimm

E38-200
Tri-rad probably holds its shape better but I doubt lasts longer. Service life depends more on weight of cloth and usage.

My lazyjacks are light Spectra, fixed to sides of boom (not under it), most-aft fastener position on boom dictated by longest full-length batten. Key is passive lines attached to spreaders about a foot out from mast. That spreads the lines a little for easier hoist (lazyjacks require boat headed accurately into wind on hoist, with some fiddling so battens don't foul.)

I spent five years with a slotted lazyjacks sail cover (56 snaps) and my new sail cover will not have slots. I'll tie away the lazyjacks before sail cover goes on. Those 56 snaps drove me bonkers, and flap-over slots in the cover allow rain water to run down the lines and penetrate to the sail.

View attachment 45122...View attachment 45123..View attachment 45127
That's a lot of snaps! Are your lazy jacks part of a kit or did you rig them yourself?
 

Christian Williams

E381 - Los Angeles
Senior Moderator
Blogs Author
No kit necessary, I had a rigger do it since I no longer climb masts. No blocks needed just thimbles in the eye splices. Spectra very slippery.

Correction: 38 snaps. (I recounted on the photo). Dunno where I got "56". But 38 is enough to disrupt sanity.
 

Puget sailor

Member I
Hi Jeff, I'm no expert, but from my research the reason the tri-radials have a longer life, which is perhaps slightly different from "lasting longer" has to do with the orientation of the cloth fibers in relation to the stretching loads. So by lasting longer what I understand is, they hold their aerodynamic shape longer, and maintain windward efficiency longer. Not to be confused with wearing out from chafe, uv, etc, which is a different concern. The tri-radial and crosscut seem to be similar in terms of wearing out, it's even possible the crosscut has a little advantage, so for the Joshua Slocum types, it's possible crosscut would make more sense. Also might be more durable if primarily downwind trade wind sailing, but I'm not sure about that.

The nature of non radial sail cloth is that there are fibers woven in perpendicular directions, and the way cross cut sails are made, the strains end up trying to stretch the fabric in directions which are not aligned with the orientation of the cloth fibers. By weaving crosscut fiber very tightly from synthetic fiber (as opposed to the ancient and short lived cotton) and then coating the cloth with some sort of resin, it is possible to stabilize the cross cut fabric from permanent stretch for a while, but not for too many years. A lot of it seems to come down to the durability of the that coating which is trying to lock the fabric grid in place.

In the case of tri-radial, the reason for the funny looking fabric pattern is to get the fabric's strongest and least stretch prone orientation in line with the strains on the sail. And since the fabric will be primarily strained in only one direction on the sail, they use special fabric for the purpose which puts more of the fabric in direct alignment with the stress, rather than trying to make it balanced for diagonal loading as in the case of cross cut sails. So the sail is less stretch prone because of the design layout, and the type of cloth that's possible to use when cut that way. A double win. It seems to be a fairly recent development to have specialized fabric for tri-radials. I believe in the first draft versions, they just oriented normal sail cloth so that the more stretch resistant of the two orientations aligned with the loads. As the sail became more popular the fabric folks seem to have said if that's what you are doing, we can make it even better. One downside on the cost front vs crosscut, a bit more labor to sew it all up, and bit more waste because of all the funny shaped pieces. I suspect modern software is pretty good at minimizing that waste though, by puzzling the pieces that can be used into a well nested template. I also suspect that modern software make the whole process of figuring out a proper 3d sail shape much easier compared to what must have been a seat of the pants affair way back when, even for crosscut sails.

Bottom line seems to be that airfoil shape is more durable in a tri-radial due to the design of the sail, and the special cloth they are able to use. For me it will be new territory to have a sail that's not decades old and really only efficient on a beam reach or downwind run. Since my E32-3 furling genoa is NOT original, and seems to work pretty well, I can really appreciate the windward potential of the boat, and I can see in the old main shape that it's not contributing much to that forward progress if I sheet it in to where it seems like it should be. The draft looks too far aft, and the back half of the sail seems to be countering any pull in the forward half, and most likely creating plenty of drag too. Not to mention the tell tales are telling tales of air flow chaos up there! I can never seem to get them all going in the same direction going to windward. Might be part of my learning curve, but I would expect a sweet spot in there somewhere and it's been elusive.
 
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Puget sailor

Member I
In reply to Frank Langer, thanks for the note on UK in Sidney. I spent some time up there when my kids were in summer ice hockey camps nearby, and really enjoyed the town. Nice to have a connection to it through my future sails. The UK loft seems to be trying to keep the gap between offshore lofts and local loft to a modest level. I've not heard very consistent reports regarding the few local lofts remaining down here in Seattle. There used to be several to choose from, but it seems to be getting flakier and more expensive all the time, and the rest are reps for various offshore lofts.
 

N.A.

E34 / SF Bay
FWIW, I go a new main a little while ago, and:

1) I wanted the Tides Marine "Strongtrack", and was going to get it, and... it turns out installing it would have required routing out a bunch of my mast track to get it in, and local boatyards suggested that was a bad idea to try to do without taking down the mast to be able to work on it. Result: I did not get the Tides track. Lessons: 1) Check installation on that track before you buy it, and (worse) have a main already built offshore and hard to modify with the special slides that go with that track. 2) I used a local sailmaker; cost me more, but they caught this issue, checked with local yards, and helped me assess the options... worth every penny (for that and more). I would have otherwise been stuck with a main built to only work with a track I could not install easily.

2) There are different slide options -- I have some (forget the name - sailmaker picked them, after coming and checking my last track and testing some in it) that slide pretty well in the existing track. Much better than the little old ones on the stock sail.

Note: I added a cam cleat to the mast so I can raise the main standing at the mast. Way easier/less friction, which helps since I do not have the supposedly magicaly low-firction Tides system. Cleat is placed such that when you go back and tension the halyard from the cabintop winch, the line pops out of the cam cleat (so not easy to slack it if you want). This was a fairly cheap and quite nice addition (again suggested, including cam cleat placement so line pops out, by local sailmaker -- having a pro look over my boat, even in a cursory fashion as they do other things, has paid off in all kinds of ways.)

3) I got a 3rd reef, set so it would match the offshore requirement for some races that one have a trysail (which I do not want to buy) or a reef going to 50% (forget whether that's 50% luff or 50% area; suspect luff). I will rig it when going offshore. One sailmaker told me to not do a 3rd, and only add later if I really needed it, since the extra cringles increase wear on the sail. I got one anyway, but FYI. (I did not want my 1st, 2nd reefs to be over-deep, since where I sail I use them quite a lot. I decided I'd rather have a 3rd reef than a super-deep 2nd.) I have sailed in up to a bit over 30 kts with the new main; I was OK with the 2nd reef (and a cut-down 90% jib, fully open, plus feathering like crazy) until the top end of that. If I was going to be out longer in 30+, I would have gone down to the 3rd reef I think. You will know whether you ever plan to sail in that kind of wind. I will second the comments here that my Ericson sails very well under jib alone; often I do that when I am too lazy to deal with the main, and it is one alternative to a 3rd reef.

4) I got 2 full (but tapered; apparently this is better) battens up high, and 2 partial battens down low. I am quite happy with this. Did this on sailmaker's advice (who knows the local conditions and has sailed everywhere I want to sail. C.f.: "glad I went to local sailmaker".)

5. Sailmaker also suggested I stay with boltrope-footed main, as was the original. Forget why; I am happy with it.

Christian's advice re: the mainsail cover and lazy jacks seems (as usual) awesome... I need a new main cover, and think that just changed what I will do re: that. I completely hate all the little zipping and snapping required to deal with the lazy jacks and the cover.
 

nquigley

Sustaining Member
I just got back this weekend - my sail made it through customs OK (incl TSA inspection) - I paid $100 for excess baggage.
Sail was designed, cut and built in this loft (Willis Sails, Kerikeri, NZ). It was fun to see the loft, meet the sailmaker and also the loft owner (Craig Gurnell) who is in the pic explaining how the batten pocket is secured (4 tapered battens: top is full-length. 8.5 oz Contender premium dacron, all seams are triple stitched, low-friction rings on leech for reefing (as well as conventional grommets), over-the-head dyneema leech line with jam cleats in the luff at each reefing clew (3rd reef is at 50% luff position to meet NZ off-shore category 1 regulation), adjustable-length dyneema dogbones.
Total cost was US$1,850 - It would have cost ~US$2500 if shipped to US by FedEx.
The US dollar is very strong at the moment vs $NZ.
battens.JPEGclew.JPEGhead.jpg
 

Pete the Cat

Member III
Don't want to sidetrack this discussion, but I think this fits: I used two different main sail stowing systems; lazy jacks on my Tartan (where I use the same stow systems to avoid snaps).. Works fine, but I did not position the lines correctly on the boom and it is a bit unweildy--pay attention to what Christian suggests about positioning. I put a Dutchman system on my Ericson and like it a bit better. Folks complain about the fish line degrading in UV and it does if you leave it out--- and it could be snap problem in that case--but I found that it is quite easy to drop the whole system and fold it in with the sail before you put the cover on (hold the boom up with the main halyard)--that way there is nothing outside exposed to sun and there are no special zippers or snaps required. The Dutchman on a new sail seems to train the sail better than lazy jacks and I am an old single hander so this is really important.
On the triradial vs. crosscut sails--my sailmaker friend says that a main weakness in all sails is the thread. Although they try, they cannot protect it from sun as much as the cloth resins do, and abrasion works on it, so I am thinking that another aspect is how many seams and thread you have. This suggests some wear issues and probably underscores the need for triple stitching (if you can convince them to do it). FWIW.
 
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