Will Asymmetrical Spinnaker work?

Calif. Ted · Feb 19, 2020

A "bit" small should still work well for cruising, racing it'll still work just not quite as good as the guy maxed out.

Ted · Feb 19, 2020

If you're going to attach the tack to a bowsprit or other strong point at deck level, the sail will be too small. If you use an ATN tacker over your furled headsail, it will be a better solution because the tack can rise up to compensate for the shorter luff. Don't forget that the addition of a spinnaker sleeve will add about a foot to the overall luff length if you decide to use one. What's more important than the design rig dimensions is the actual dimensions of the sail.

JRT · Feb 20, 2020

Ask Precision Sail to give you a price for new, Ron should contact you by email after you send in a request for quote and he spends time talking about what your needs, experience and conditions will be to help make the right sail. They are not the same level as North of course but I always like to cross check the 'deal price' against an estimate from Precision because I have had very good experiences with them. I'm waiting on our Code 0 custom pink and logo right now just like you for a good lite wind day. I checked with several lofts on my requirements for what I needed and they all said I needed a Code 0 vs an asymmetrical. My Code 0 was 1/3 the North price from Precision too.

Hunter216 · Feb 20, 2020

pumpkinpie said:
The sock is not included. We were offered two different options - an ATN or a Chute Scoop. Is one any better than the other?

Have you considered using some of the savings in getting a top down furler instead of a sock and/or a bowsprit?

DrJudyB · Feb 20, 2020

Get the actual measurement of the luff of the sail. From head to tack , switch the luff pulled gently into a straight line.

Measure your boat’s maximum available spinnaker hoist . Hoist a measuring tape up to the top using the spinnaker halyard, down to the place you will run the tack line.
If you don’t have a spin halyard yet, use the Genoa halyard pulled to the tach attachment point, and ad about 2 feet.
This is the “Max spinnaker hoist”
(This maybe a couple of feet shorter than you'd calculate using I and J and the Pythagorean formula)

As a first approximation, take 95% of the Spinnaker Max hoist, for using it on a boat with a snuffer and a traditional pulpit.

For a more accurate estimate:

Subtract the height of the bow pulpit ( since you will be flying the sail above the top rail)
Subtract about 1.3 foot for the head pendant in the snuffer.
Multiply by 0.99 (for a cruising chute, not a racing chute)
That's your luff length for the asymm
The result is the longest maximum luff of a cruising G2 for an asymm used with a snuffer...
... give or take a little

*Generally, the leech should be about 93% of the luff, depending on other measurements of the boat's deck hardware.

* Generally, the Foot about 162-167% of the J + distance between forestay and tack attachment point, depending on etc

* Generally, midgirth about 85 to 90% of the foot, depending on etc

~~~~~~~~~~~~~~~~~~~~~
These are only estimates for a general purpose cruising asymm cruising chute, that is designed primarily for stability and is easy to trim. Actual Dimensions will vary according to the particulars of the hull form, rig type, weight, tack height above water level, sheet block above water level, etc.

In general, if I were buying a used asymm, I’d personally rather get an Asym that is too short on the luff than two long. The flying shape would be unstable if you ease the tack line to sail a deep angle.

I personally wouldn't want a racing asymm with a very wide midgirth and and draft position and depth for cruising. It can be tricky to trim.

Judy

Meriachee · Feb 20, 2020

Yeah. What Judy says. And, as also mentioned, factor in where the tack is. Adding a pole can add 5-6 feet to the luff length.

DrJudyB · Feb 20, 2020

Hunter216 said:
Have you considered using some of the savings in getting a top down furler instead of a sock and/or a bowsprit?

The OP will need either a bowsprit or need to modify the bow pulpit to use a furler.
And the luff needs to be not overly long to use a top down furler. If the luff is too long, it won't furl as well. How much to shorten the luff depends on the brand and model of the top down furler.

I love top down furlers, and highly recommend them, but they do add additional cost to the package.

Judy B
Semi-Retired sailmaker

DrJudyB · Feb 20, 2020

@pumpkinpie

If you want an informed answer, you'll have to post the sail's actual dimensions. BTW, it's totally reasonable to ask the current owner for the dimensions. It should be right on the invoice from when he purchased the sail.

Get the sail measurements for:
Luff
Leech
Foot
Mid girth (aka half girth), if possible.

Then use a tape measure the real dimension from the top of the spnnaker halyard hoist, down to the place where you'll attach the tack line.

With that info, I can give you an informed opinion. I would never sell a sail based on just the published I and J.

Judy
Semi-Retired sailmaker

Meriachee · Feb 20, 2020

No other language here. The sail needs to fit. If it doesnt, it wont “work” properly. Probably a good idea to waste a few quality minutes with dr Google and figure out how to attach it, hoist it, and fly it. All three of those things are over and above how big it is.

sailboatracer · Feb 20, 2020

If you're thinking about adding a bowsprit, there's one listed in the classified section. Looks like a Trogear unit.

Meriachee · Feb 20, 2020

I wasn't necessarily referring to making it go, the tack matters to the luff length, its different for a sprit, than say a bobstay cleat, and if you have, need, or need a bigger crane at the masthead. Our top-down required a much bigger crane for clearance with the swivels, and while that bit doesnt matter here, it did alter the length of the sail. Suddenly, a sail that was way too big, was a couple feet shy of what it could have been.
A sock with a collar can get bound up, or chafe on the headsail.

Hunter216 · Feb 20, 2020

pumpkinpie said:
I do understand how to attach, hoist, and fly.

I grabbed the image above to hopefully assist in the conversation. It looks like the forestay/furler on your boat doesn’t go to the top of your mast and attaches to the hull just behind the roller for the anchor. I don’t know if you already have a spinnaker halyard but it would have to be above the forestay/furler point and the anchor point for the tack of the new asym would have to be in “front”/“above” of the forestay/furler. There needs to be enough clearance for the asym in front of the existing hypotenuse the forestay/furler makes to allow it to fly safely. You can add a crane at the top of the mast and/or a sprit at the deck to increase the clearance if needed.

It’s kind of hard to provide input to your original question without knowing how you intend to connect the asym to your boat and accurate dimensions of the sail you are considering buying

Hunter216 · Feb 20, 2020

DrJudyB said:
I love top down furlers, and highly recommend them, but they do add additional cost to the package.

Valid point about adding to the cost however I wonder how much more someone would use the sail when they could just furl it in and out, leaving it hoisted??

I’m pretty convinced

based on casual observation of postings of people who get a slightly or never used kite with their new to them boat that a lot of sailors find big sails sort of intimidating. Being able to handle the “beast” in a manner that is already somewhat familiar (furler) removes a lot of the stress and makes it fun = more usage.

Meriachee · Feb 20, 2020

It has a deep seated, pathological desire to unfurl itself when rolled up. I have a repurposed hockey bag on the deck and it takes no time at all to hoist the assembly.

Hunter216 · Feb 20, 2020

Meriachee said:
It has a deep seated, pathological desire to unfurl itself when rolled up. I have a repurposed hockey bag on the deck and it takes no time at all to hoist the assembly.

Something tells me you don’t fall within my “intimidated” group.

Meriachee · Feb 20, 2020

Made the pole, made the ends, made the furler, made the crane, got into a huge argument with the sailmaker, learned how to sew Marlow torsion rope. Yeah, ill buy that comment for a dollar.
and one more thing, not afraid to fail, step back, re-engineer and do it again till you get it right.