Tri-radial or cross cut genoa?

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robertt

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Woe is me, my roller reefing genoa unfurled and was reduced to tatters in the recent high winds.
Before it worked loose I had tried to remove it from the boat on my own and didn't manage the week before!
Another lesson learned accompanied by the sound of money going down the drain.

Anyhoo, I'm trying to acquire a replacement and have been looking for a used sail with the correct dimensions. Boat is a Trapper 501 and dimensions are Luff 33', Leech 31', Foot 19'

Hard to find one exactly to match so might have to compromise on foot size being shorter, don't think I can accept a different luff size. None of the nearby sailmakers have anything suitable so looking online and...

Found one pretty cheap from Exchange Sails perfect size match except foot is 17' and it is tri-radial, described as good condition

I thought tri-radial sails were usually more expensive

But my main query is does this mean it can't be used partly rolled away as a form of reefing? Will this damage the sail?

Sorry I'm still quite new to all of this
 
sailorman said:
Try Crusader C cut ( Bi-radial)
Tri radial is these days means a laminated cloth ( well thats what i was told by a sail maker)
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No, I have a tri-rad in Dacron, from North.

Snowbird16-5-10crop.jpg


To the OP - tri-rads do furl.
 
A tri-radial is cut to allow better spreading of the forces in the cloth and generally is more expensive than a cross cut .Tri-radials can be of varying material but are more used in the less cheaper materials and particularly laminates.
Tri-radials furl as well as cross cut sails and better if they have a foam or rope luff.
I have a tri-radial laminate genoa and it sets beautifully and is now 7 seasons old.
Cross cut sails in non laminates will stretch progressively whilst laminates will stretch hardly at all until the day they fail when the laminates become detached with a bang and you no longer have a sail.

You may need to do a search against Exchange Sails on this website.
 
I remember someone telling me that tri-radial sails need to be either rolled right out or rolled away, and not partly furled, as this can damage the sail due to stress in the wrong direction/place on the sail? Is that not really an issue in practice?
 
robertt said:
I remember someone telling me that tri-radial sails need to be either rolled right out or rolled away, and not partly furled, as this can damage the sail due to stress in the wrong direction/place on the sail? Is that not really an issue in practice?
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That's what Hood told me. The forces on a reefed tri-radial lie across the weave, resulting in stretch. Reefing a cross-cut does not have the same effect, the forces are always with the weave. However, for long life a cross-cut needs to be made in superior cloth such as the Vectran I have had for twelve or more years with no discernable stretch. The previous Dacron one was clapped out in three years.
 
Well I have 2 genoas (150 and 140%) cut as tri-radials by Team Sails - and designed for roller reefing. Heavier cloth for higher winds when part rolled (or so their theory went. Team Sails became Sobstad and I had a cross-cut roller reefer made by them (fortunately it blew to tatters in Monfalcone). The latter was a horrible sail.
After 25 years and 27 years respectively, there's no foam luff in either of the original genoas and one is on its 3rd UV strip.
I'm now getting a biradial 110% Dacron genoa from Crusader - the alternatives were radial, Spectra re-inforced, PE or cross-cut Vektran.
From what I gather, fabrics and usage dictate the cut of the sail. You'll never find Vektran (absolutely the same stretch in woof and warp) in anything but crosscut.
But no self-respecting sailor would be seen with a cross-cut main - unless it were fully battened and my experience of radial cut sails is they set better and keep shape longer - I'd certainly NEVER have another crosscut foresail.
In fact big overlappers are only good for reaching, they don't roll down to a good shape and you need a much narrower slot for good windward performance than your average genoa shheting angle allows you.
One wonders why we ever bother with roller genoas...:ambivalence:
 
charles_reed said:
One wonders why we ever bother with roller genoas...:ambivalence:
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Charles, you've obviously forgotten the joy of changing headsails on a dark and horrible night, with the foredeck going up and down like a demented bungy jumper.

And then bundling the sail that's been replaced down below wet and dripping. What fun!
 
Twister_Ken said:
Charles, you've obviously forgotten the joy of changing headsails on a dark and horrible night, with the foredeck going up and down like a demented bungy jumper.

And then bundling the sail that's been replaced down below wet and dripping. What fun!
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Thanks a bundle. You've brought my nightmares back to haunt me all day and probably night.
 
Tri-radial laminate. Coming up to its 10th anniversary. On its second UV strip. No stretch, sets beautifully still and reefs like a dream (thanks to foam luff).

Only downside is it got the mildew problem to which sailorman referred back in post 5 when only a year or so old - so it ain't the prettiest sight, but beating efficiently to windward when well reefed is more important to me than appearance.
 
robertt said:
How does a foam luff help?
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The foam in the luff is triangular in shape and that means different amounts of sail along the length of the forestay are rolled up as you reef, thereby maintaining an efficient shape. Never looked in detail at what it does, but I think the sail flattens the more it is furled since more of the middle of the sail gets rolled away than at the head or tack.

Works great even with (the equivalent of) 2 or more reefs.
 
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