Rigging an asymmetrical spinnaker

[jalmberg]

The original Joshua, to give you an idea of what I'm aiming for.

[jalmberg]

Our Joshua in the Chesapeake a couple of weeks ago...

[Sardean]

What a lovely yacht

[James S]

Originally Posted by jalmberg

Our Joshua in the Chesapeake a couple of weeks ago...

Lovely looking ...

[rgleason]

The lazy sheet can be run inside or outside depending on ...boat, wind, preference, experience. Since it is in a sock, it is easier to douse singlehanded.

[Suijin]

Originally Posted by Sailmon

PO is previous owner. Still seems strange to me that he would only use one sheet. Sails & snuffers are not not inexpensive. Can’t understand scrimping on the line. Wondering if there were originally 2 sheets & one got repurposed. Did the boat come with turning blocks for both port & starboard. At any rate, if you plan to use the chute with any regularity, it would probably be a good idea to invest in a second sheet.

I fly my asym single handed and use a sock. To gybe it I sock it, rerun the line, then unsock it. Way easier and much less to go wrong than trying to manage two sheets, gybe the main, and steer at the same time. And I only fly it on long tacks in settled weather.

When you say “very long sheet” exactly how long is it? It’s possible it’s just a repurposed line or old halyard.

I use dyneema for my sheet...inexpensive, thin and light, easy to stow. Just make sure you’ve got gloves on in anything more than a whisper of wind.

A “prod” is essentially a bowsprit specifically designed for flying asym kites. Many boats, particularly racing, will leave the jib up with the asym. The prod creates the slot.

On your boat you definitely want to run the lazy sheet outside. Too much to get hung up on and tear the sail running it inside. You only rig that way if you have a clean deck/prod area and the crew to manage the sail through the slot.

[EmeraldCoastSailor]

While I have two asym sheets I find myself flying my Green Monster with only 1 attached because I rarely need to gybe given my typical sailing habits. When I run with two the lazy does go in front of everything around the bow and you have be very aware of what the lazy sheet is doing. When gybing if you tend to the lazy sheet and go slow you can keep the sheets out of the water. My bow anchor is another matter as a sheet can get under the anchor if you don't pay attention. With crew two sheets are not as much of a problem.

[Dave22q]

You pretty much have to plan on an outside tack as your downhaul will be forward of the forstay. You just have to manage both sheets at the same time keepiung both out of the water. Sounds harder than it is.

[meirriba]

If you intend to jibe the asymmetric every so often, you will want 2 sheets.
If you intend to sail long times on one tack before jibing, one sheet will be enough.
The 2 sheets should have each length more or less twice the length of the boat, i.e.for 40ft boat, each sheet should be at least 80ft.
There are basically three ways to jibe.
1. Easiest - snuff it with the snuffer, jibe the boat, open asymm. on new tack.
2. Inside jibe - install sheets like normal genoa, but lazy sheet passes between asymm. and headstay.
It would work only if asymm. tack is far in front of headstay like on a bowsprit.
It works best in light winds and a crew have to go to the bow to pull the lazy sheet with the clew between asymm. and headstay to the new side.
3. Outside jibe - the lazy sheet installed in front out of asymm.
Jibing you go downwind and let go of working sheet until asym. flies in front of boat like flag and then you complete jibe and tighten old lazy new working sheet.
Works if wind is strong enough to fly sail and sheets forward.

If you rig sail in one of the 2nd or 3rd options and the wind changes to make jibe uneasy you may always revert to option 1.

[Nicholson58]

Jalmberg,
If your foredeck is as complicate as you avatar indicates you may want to bag the kite and re run the sheet. Our deck has four stay, cutter stay lower stay. Pulling a spin set and spinnaker through is a likely tangle. Taking it around the bow might twist the retriever line in the sock. For running way off we use a pole and rig it traditionally.

Run your sheet to make the sail fly correctly. This is probably not to the stern especially on a Ketch. Ours sheets about mid ship. The code zero below sheets and flies much like an AS.

[DEAN2140]

You can set up the spinnaker for an outside or inside jibe. The instructions you cite are for an outside jibe. I wouldn't release the old sheet but begin hauling in the new sheet once the clew goes forward of the forestay. Otherwise you may get a wrap. There should always be some tension on the clew as it passes from one side to another.

I would also suggest trimming (centering) the main before the jibe to keep some pressure on the spinnaker. If it collapses you risk a wrap.

The sheets should be sized to your ST winches, probably 3/8's or so with some elasticity so the spinnaker doesn't take all the shock of a puff.

If you don't use a sock, best to do the takedown on the weather side with someone on the foredeck pulling on the weather sheet. Some sails have a belly cord in the center of the sail. Sounds like a good idea but I don't have experience with it.

Practice in 10 knots or so and experiment with an inside jibe to see which works best for you.

Good luck.

[FabioC]

The asymmetric with the sock is one of my favorite topics...

The most likely reason why the PO only used one sheet is that an asymmetric with the sock is almost impossible to jibe while flying it (also, the risk of getting the sock stuck and having to go up the mast to free it is too high to justify).

So, as others have said, with a sock, most people do not jibe with the spinnaker flying. Those who do, jibe the spinnaker by lowering the sock and then passing the whole thing to the new side and then taking the sock up again.

If you do not plan to jibe the spinnaker at all, using one sheet is a reasonable option in the name of simplicity, just rig it on the side you plan to fly the spinnaker.

Even if you jibe the spinnaker with the sock, since you are lowering down the sock anyway on the jibe, if you pass the lazy sheet "outside" (like in an outside jibe), as it is the case in many boats, it makes sense to only have one sheet attached to the clew at all times, so you do not have to bother making sure that the lazy sheet has some tension and does not fall in the water (and gets stuck in the keel and you have to clean up the whole mess...). You can simply attach the lazy sheet to the clew as you pull the sock down (you will have full control of the clew at that point), detach the old sheet, pass the sock around using the new sheet, take up the sock and you are flying on the other side without worries.

[Jerry Woodward]

I have only flown my asym spinnaker a few times so far, but I began wondering, why not reuse the genoa sheets when I fly the spinaker since the genoa will be furled? I could simply use a soft shackle to attach the genoa sheets and when I'm ready to hoist the spinnaker, unshackle the leeward sheet and attach it to the clew of the spinnaker. To jibe, I would lower the sock, and switch to the other genoa sheet. Thus, there would always be one sheet attached to the furled genoa to keep tension on the wrap. Yes, I would need to route the genoa sheets to the outside, but I do that anyway depending on whether I'm downwind or upwind. Two less lines to worry about!

[FabioC]

Originally Posted by Jerry Woodward

I have only flown my asym spinnaker a few times so far, but I began wondering, why not reuse the genoa sheets when I fly the spinaker since the genoa will be furled? I could simply use a soft shackle to attach the genoa sheets and when I'm ready to hoist the spinnaker, unshackle the leeward sheet and attach it to the clew of the spinnaker. To jibe, I would lower the sock, and switch to the other genoa sheet. Thus, there would always be one sheet attached to the furled genoa to keep tension on the wrap. Yes, I would need to route the genoa sheets to the outside, but I do that anyway depending on whether I'm downwind or upwind. Two less lines to worry about!

Well, sharing genoa and spinnaker sheets does not work too well because the leads are in different positions (the spinnaker sheet lead blocks are towards the stern, the genoa's are much forward). Also, for the spinnaker, the sheet has to come into the lead from outside the life lines, so you typically have lead blocks on the rail.

Sharing sheets works very well between Code 0 and Asymmetric.

[jalmberg]

Originally Posted by FabioC

The asymmetric with the sock is one of my favorite topics...

The most likely reason why the PO only used one sheet is that an asymmetric with the sock is almost impossible to jibe while flying it (also, the risk of getting the sock stuck and having to go up the mast to free it is too high to justify).

So, as others have said, with a sock, most people do not jibe with the spinnaker flying. Those who do, jibe the spinnaker by lowering the sock and then passing the whole thing to the new side and then taking the sock up again.

If you do not plan to jibe the spinnaker at all, using one sheet is a reasonable option in the name of simplicity, just rig it on the side you plan to fly the spinnaker.

Even if you jibe the spinnaker with the sock, since you are lowering down the sock anyway on the jibe, if you pass the lazy sheet "outside" (like in an outside jibe), as it is the case in many boats, it makes sense to only have one sheet attached to the clew at all times, so you do not have to bother making sure that the lazy sheet has some tension and does not fall in the water (and gets stuck in the keel and you have to clean up the whole mess...). You can simply attach the lazy sheet to the clew as you pull the sock down (you will have full control of the clew at that point), detach the old sheet, pass the sock around using the new sheet, take up the sock and you are flying on the other side without worries.

H'mmm, this makes a lot of sense. We would probably only use the spinnaker on long offshore legs, since I don't like to run the engine offshore. I'm guessing this is what the previous owner did too.



I never thought of the problem of getting something hung up in a jibe, but that is yet another worry to add to the fear of running over the lazy sheet or the sail itself during a jibe.



At least in the beginning, I think it sounds very sensible to sock it before jibing, if jibing is ever necessary.



Thanks for sharing your experience.