Spinnaker sheet & guy sizing

[sailoppopotamus]

I have a 62 sqm symmetric spinnaker for my 30ft boat that I've never used, because I'm a coward and afraid of it. I'll have to start using it this year, so I'm looking for advice as to what sheets to buy. Sailmaker suggested the sail (0.86oz) should be good to 20kts apparent, which is way more than I intend to fly it in. Force 3 (true) is about the maximum I'd be comfortable hoisting it in, but the beast is coming down as soon as it looks like Force 4 (true). Maybe next season I'll have the courage to fly it in stronger winds.

The tentative plan is to fly it with single sheets (and barber haulers). I'm looking at polyester ropes, which are cheaper, and the flex might help save my spinnaker and associated hardware when I inevitably let it fill with a bang. Looks like 2xLOA is the appropriate length. What about diameter? 8mm or 10mm? Given my plans, would it make more sense to go for 6mm sheets now given the wind strengths at which I intend to hoist it in, and buy a second set of 'heavy-air' 8 or 10mm sheets next year?

Any advice from people with spinnaker experience would be greatly appreciated.

 

[Tranona]

"strength" is largely irrelevant for sheets. It is handling comfort and weight, particularly in light airs. For a similar size asymmetric I used 10mm, but could have used 8mm. Liros braid on braid.

 

[Shuggy]

Sounds like fun! We were spinnaker novices once upon a time and when we're using it I suspect we still look we are... but if I could offer one suggestion it would be to set yourself up with sheets and guys from the get-go as it makes life much easier, and if you're on a learning curve you might as well go for the end game and learn that. For example, a lazy guy can be really useful if you want to get the kite down in a hurry when the wind gets up - the letterbox drop is something we've used a few times both when cack-handed racing and also with the family when the wind gets up. There was one memorable occasion when we stupidly still had the kite up in 35 knots true with the ancient boat doing about 13 knots through the water and there was no option other than a letterbox drop. I suspect it saved the boat that day. We needed a lazy guy so having only a two line system wouldn't easily have provided that option for us. Also, if you have a guy you can ignore the barber hauler if things get a bit exciting and just concentrate on the guy, which will be attached to the right point of the boat to be effective.

Our spinnaker is 133 m2 and we have a very pinched stern (which makes a guy essential) but I suspect the same principles apply.

 

[sailoppopotamus]

Point taken on the guys & sheets. I have a lazy bag so with my present setup the spinnaker would foul on the lazyjacks if I were to go for a letterbox drop down. The tentative plan is to dump the guy and halyard and collect the spinnaker from the sheet into the companionway under the boom (but not between boom & mainsail). I'm not sure how the double sheets would work on my boat, I only have 2 winches on either side, but will definitely consider it. Would that basically mean four lines, 2xLOA, 8mm for sheets and 10mm for guys? That's a lot of line, we'll look like fishermen untangling nets in the cockpit

 

[Shuggy]

I also have two winches on each side but it's not a problem. I use the main winch for the guy and the spinnaker (second one) for the sheet. Our sheets and guys are both 12mm but in light airs the sheets are too heavy so we rig up something else. You don't need 2 x LOA for guys - I think ours are roughly 1 x LOA.

 

[penfold]

Up to 10kts 8mm is ample and would be readily hand trimmable through a ratchet block; 15-20 would be perhaps become uncomfortable over long periods if hand trimming.

 

[Concerto]

I set my spinnaker singlehanded on my 32ft ¾ rigged Westerly Fulmar in winds to 20 knots. Getting up is easy, but I do not use the letterbox method when dropping. My trick is to use a snatch block on the sheet, fixed on the rail at the end of the coach roof. When the guy is tripped the leech is behind the mainsail, then I release the spinnaker halyard but leaving one turn on the winch - which is sufficient friction to stop it just dropping. The spinnaker goes into the cockpit well and then I set the course and sails, then tidy all the spinnaker gear up.

sailoppotamus, spinnakers are not that scary to use. The conditions you are going to try using your spinnaker in will have very light loads and winches would almost be unneccessary. You may enjoy this short video of Concerto under spinnaker whilst under autopilot.

 

[William_H]

There is a fleet of 36ft racing yachts here and I have sailed on them. Spinnaker set up is simple with a sheet to each corner of spinnaker. One becoes guy if it is to windward and carries the end of the pole. Each sheet goes through a barber hauler (down haul) which meets the gunwhale A bit before the front of the cabin. Hoist is out of the front deck hatch. With a crew of 6 in a race spinnaker is also pulled down into front hatch.
However on those boats and also on my own little boat if things are a bit rough we pull the spinnaker in under the boom into the cabin. So guy is released, person in the cabin hatch (with a boat hook ) grabs the sheet and pulls it all in under the boom releasing the halyard at the same time. Hopefully enough length in the sheet (guy) to get all spinnaker inside. If not enough length you have to remove stopper knot and pull spinnaker plus sheet right through barber hauler and pole end.
Yes I would not go less than 10mm polyester braideven a bit longer than 2xwl. What I did do long ago was got an old spinnaker and cut it down to about 1/2 big spinnaker size. This is done by folding over the middle and sewing down the new middle to make spin much narrower but full height. This spinnaker can give you confidence and is still a boon to ail area and of course not such a devil when wind gets up.
Remember keep the boat under the spinnaker turning down wind if boat starts to heel when away from dead down wind. Dump the main sheet as soon as agust appears. Ah the madness. ol'will

 

[michael_w]

Invest in dyneema for the guys. Anything else is just too stretchy.

 

[bignick]

For a 30’ boat you don’t need separate sheets and guys - it’s unnecessary complication.
I’ve raced boats of this size for years and have never used them. You only need separate sheets and guys when you get to about 36’ and upwards.
I’d recommend you go for 10mm, for handling reasons, but would suggest you go for dynema. The stretch in normal braid on braid makes keeping the pole off the forestay a challenge on a tight reach. Oh, and make sure you fit the plastic balls or discs to prevent the snap shackle jamming in the pole end.

 

[Chiara’s slave]

We have found ourselves using 2 sets of spinnaker sheets, one for light airs, to help it fly, one for when theres a bit of weight in the wind. The light wind sheets are strong enough for anything, but hard to grip. If we get caught out with increasing wind, they go on a winch from about 8kn, less if reaching. We now use a snuffer. That’s a much debated bit of kit here, but it’s made us brave enough to use the kite more, we’re almost always 2 handed, the kite is 65m sq.

 

[awol]

There is a fleet of 36ft racing yachts here and I have sailed on them. Spinnaker set up is simple with a sheet to each corner of spinnaker. One becoes guy if it is to windward and carries the end of the pole. Each sheet goes through a barber hauler (down haul) which meets the gunwhale A bit before the front of the cabin. Hoist is out of the front deck hatch. With a crew of 6 in a race spinnaker is also pulled down into front hatch.
However on those boats and also on my own little boat if things are a bit rough we pull the spinnaker in under the boom into the cabin. So guy is released, person in the cabin hatch (with a boat hook ) grabs the sheet and pulls it all in under the boom releasing the halyard at the same time. Hopefully enough length in the sheet (guy) to get all spinnaker inside. If not enough length you have to remove stopper knot and pull spinnaker plus sheet right through barber hauler and pole end.
Yes I would not go less than 10mm polyester braideven a bit longer than 2xwl. What I did do long ago was got an old spinnaker and cut it down to about 1/2 big spinnaker size. This is done by folding over the middle and sewing down the new middle to make spin much narrower but full height. This spinnaker can give you confidence and is still a boon to ail area and of course not such a devil when wind gets up.
Remember keep the boat under the spinnaker turning down wind if boat starts to heel when away from dead down wind. Dump the main sheet as soon as agust appears. Ah the madness. ol'will

"Stopper knot"? Certainly not on my boat! Halyard, sheets and guys never have stoppers just in case sh*t happens and it is deemed necessary to dump the lot quickly. In my case there was enough air in the cloth to keep it floating for retrieval. I'd rather lose the kite than a crew member!

 

[Bobc]

Anything less than 10mm will shred your gloves. Don't waste your money ey on Dyneema.

 

[sailoppopotamus]

Thanks to everyone who replied. Most seem to think that 10mm is the way to go so I'll do that. I somewhat committed to this choice today by buying two 10mm boat-priced plastic shackle guards . Dyneema is way out of my budget, so it will have to be polyester.

I've been on boats where it's indeed been difficult to keep the pole off the forestay on a beam reach. It was actually scary how much tension was on the guy. Either way, whenever we tried to sail such high angles something invariably went wrong and we ended up losing more time than we gained compared to flying a genoa. So I think I'll stick to deep angles, in light airs. I know we won't be competitive, and I'm perfectly fine with that. Everybody on the boat including me is clueless and we've never flown a spinnaker before, so I'm happy if we pass at least one boat.

 

[William_H]

Thanks to everyone who replied. Most seem to think that 10mm is the way to go so I'll do that. I somewhat committed to this choice today by buying two 10mm boat-priced plastic shackle guards . Dyneema is way out of my budget, so it will have to be polyester.

I've been on boats where it's indeed been difficult to keep the pole off the forestay on a beam reach. It was actually scary how much tension was on the guy. Either way, whenever we tried to sail such high angles something invariably went wrong and we ended up losing more time than we gained compared to flying a genoa. So I think I'll stick to deep angles, in light airs. I know we won't be competitive, and I'm perfectly fine with that. Everybody on the boat including me is clueless and we've never flown a spinnaker before, so I'm happy if we pass at least one boat.

My little boat initially came with a "whisker pole" use to push out the guy from the mast to aid the angle the guy takes to the spinnaker when really shy. ie to pull guy off the forestay. No I never used it. Just put up with difficulties of guy on forestay. OP is right to avoid sailing shy with spinnaker. It really is madness in a strong wind and any gains can be easily lost with a round up.
From AWOL "Stopper knot"? Certainly not on my boat! Halyard, sheets and guys never have stoppers just in case sh*t happens and it is deemed necessary to dump the lot quickly. In my case there was enough air in the cloth to keep it floating for retrieval. I'd rather lose the kite than a crew member!
There is a style of figure 8 stopper knot which is not completed but left like a bow so that a tug on the free end will release the stopper knot. Though I confess I never use it. ol'will

 

[awol]

Even with Dyneema keeping the pole off the forestay can be difficult. I use a jockey pole to give the guy a reasonable angle. It's easiest if it is rigged before it is really needed and if the wind goes aft it just frees itself. The boat in front is using a jockey pole

 

[flaming]

I have a 62 sqm symmetric spinnaker for my 30ft boat that I've never used, because I'm a coward and afraid of it. I'll have to start using it this year, so I'm looking for advice as to what sheets to buy. Sailmaker suggested the sail (0.86oz) should be good to 20kts apparent, which is way more than I intend to fly it in. Force 3 (true) is about the maximum I'd be comfortable hoisting it in, but the beast is coming down as soon as it looks like Force 4 (true). Maybe next season I'll have the courage to fly it in stronger winds.

The tentative plan is to fly it with single sheets (and barber haulers). I'm looking at polyester ropes, which are cheaper, and the flex might help save my spinnaker and associated hardware when I inevitably let it fill with a bang. Looks like 2xLOA is the appropriate length. What about diameter? 8mm or 10mm? Given my plans, would it make more sense to go for 6mm sheets now given the wind strengths at which I intend to hoist it in, and buy a second set of 'heavy-air' 8 or 10mm sheets next year?

Any advice from people with spinnaker experience would be greatly appreciated.

Don't scrimp on the material. My dad's old boat had Polyester kite sheets and guys, it was horrible, even when not especially pole forward the pole bounced all over the place, and when you did get the pole on the forestay it was very hard to keep it in the right place.

Personally I would go separate sheets and guys. It looks more complicated, but isn't. And it allows you to never, ever, do anything on the foredeck with a loaded rope. If you were then price conscious, you could get away with cheaper sheets, but definitely do not do that for the guys, you will regret it.

10mm sheets and guys would be fine. 8mm Dynema would also be fine. Just choose which you'd rather hold. The lightweight sheet thing is for real drifting conditions, and in my experience cruisers don't even bother trying to sail in that. In more than 5 knots of breeze you won't have a problem with sheet weight. For very light winds we have a literal ball of string that we tie on and fly the thing by hand if we have to. But at that point I'm normally more in favour of retiring to a decent pub....

 

[flaming]

Even with Dyneema keeping the pole off the forestay can be difficult. I use a jockey pole to give the guy a reasonable angle. It's easiest if it is rigged before it is really needed and if the wind goes aft it just frees itself. The boat in front is using a jockey pole

Ah the jockey pole....

Simply designing the boat to have a more reasonable beam negated that complication.

 

[Chiara’s slave]

Ah the jockey pole....

Simply designing the boat to have a more reasonable beam negated that complication.

I think I can safely say I’ve taken that concept to it’s logical conclusion.

 

[flaming]

I think I can safely say I’ve taken that concept to it’s logical conclusion.

Whilst also going A-sail to eliminate the need entirely....