Spinnakers, code zero, (again?)

[manisland]

I've read up on spinnakers and multihulls and code 0 etc here on CF, but I can't seem to find what I need.


I'm interested in getting a large code 0 and either a large spinnaker, or an asym.
I have a Lagoon 42, and can run head sails from the center, or from the upwind pontoon.


Here is what I can't find:
1) How big of a sail can I get?

2) How much wind can I fly it in when I get a Sailzilla?


Minney's has a huge selection, and I'm interested, but have no idea how big I can go, nor how conservative to be with the wind speeds.


How can I get a feel/sense for that without buying one, and flying it in progressively heavier air until something breaks?


Any reference to a source of information would be appreciated.

[Sparx]

Here is what i would suggest for an asymmetrical spinnaker...

Measure the length from your spinnaker halyard sheave on the mast to the point on deck where the foot of the sail will attach. Subtract maybe four feet. This is a starting place for maximum luff length, that will have the foot of the sail high enough you can see under it. Because of the arched luff of the sail when it us flying, the foot will actually be much higher than 4 foot off the deck. For starting dimensions look for a foot length of close to half the luff length.

Next decide the conditions you are targeting. For getting the boat moving in light air go with 0.75 oz cloth. Likely this sail will carry up to about 12 to 15 knots apparent wind. For down wind crossing oceans in the trades I would go with 1.5 oz cloth and about 2/3 the total square area recommended above.

[Lucid]

I have a code zero and love it. For a multi hull you may want to explore a screecher. Code zeros are for mono screecher multi to help point up wind.
The a symmetrical is more down wind the zero more up wind. Thurston Sails in RI is a great resource.

Good luck!

[manisland]

Originally Posted by Sparx

Here is what i would suggest for an asymmetrical spinnaker...

Measure the length from your spinnaker halyard sheave on the mast to the point on deck where the foot of the sail will attach. Subtract maybe four feet. This is a starting place for maximum luff length, that will have the foot of the sail high enough you can see under it. Because of the arched luff of the sail when it us flying, the foot will actually be much higher than 4 foot off the deck. For starting dimensions look for a foot length of close to half the luff length.

Next decide the conditions you are targeting. For getting the boat moving in light air go with 0.75 oz cloth. Likely this sail will carry up to about 12 to 15 knots apparent wind. For down wind crossing oceans in the trades I would go with 1.5 oz cloth and about 2/3 the total square area recommended above.

Thanks so much! That was exceptionally helpful. I appreciate it.

[chris mac]

We have a lagoon 42 tpi, 1993.
So slightly different, but similar. In terms of wind speeds, we have had our asymmetrical up and winds were building. We waited a little too long and socked it in 20 knots. The sail handled it fine, but it was a pain to bring down. So my advice would be to not use it over 15-17 AWS.
White sails should be moving you just fine there anyways.
In terms of size, I would think a sail loft would have stock info for that

[Alistair242]

Or even worth giving Lagoon a try. I’m sure they have specs for all downwind sails.
Or just speak with a sail maker familiar with Lagoons and tell them exactly which sails you would like and for what?

[davecalvert]

Yes, here we go again.
We are a multihull specialty sailmaker for over 40 years and have worked with many catamaran owners for after market down wind sails. One of the issues I see is the proper description for sails. Gennakers, screachers, Code 0s, and asymmetrical spinnakers often get mixed up. This in part depends on what part of the world and what sailmaker you are working with. In the US, we have been calling screachers a strongly built loose luff sail mounted on a bow sprit with internal anti torque luff rope, mounted on a bow sprit with a bottom up continuous line furler. This is sheeted inside the cap shrouds for upwind in light air. We build these for up to 18-20 kt. apparent winds.
The code 0 is also mounded on a bow sprit, with furler, torque luff rope, but, in lighter weight material and trims outside the shrouds to the spinnaker blocks aft on the hulls. We design these for up to 18 kt, apparent as well. For this reason, I prefer to use stronger materials than nylon. Code 0 cloths, triradial cut dacron, and some laminates are great for this. If built with heavy enough material, a light weight UV strip can be added to allow the sail to remain furled on the bow sprit for lengths of time.
The asymmetrical spinnakers can be made in a variety of sizes. Some owners want these fairly small to avoid getting caught overpowered and some want to go big. On your size cat, I would guess an asymmetrical can be from 1,100 sq. ft. to over 1,600 sq. ft. One important thing to keep in mind when buying a spinnaker is the construction. Catamaran, or multihull, spinnakers must be built quite a bit stronger than the same length mono hull sails. Some sailmakers are not fully aware of how much different. We use heavier weights of nylon, sometimes two weights for the larger boats, larger patches, double tapes and lines on all three sides, etc.
In my humble opinion, the best extra sail, over a main and jib, for a catamaran is the Code 0. Many of the boat owners are husband and wife teams. In my experience when they buy spinnakers, they end up using them very little. The hassle of dragging the sail out, setting up bow blocks, running the lines, and hoisting with a sleeve is a bit time consuming. (Unless on a long passage) In a lot of cases, shortly after setting up the sail, the wind will build and they have to reverse this process to douse the sail and put away. A code 0 made in strong material, with a UV strip, can be left rolled up for lengths of time. When sailing from upwind to reaching or down wind, it is a simple matter to roll up the jib and unroll the Code 0.

[manisland]

Originally Posted by davecalvert

Yes, here we go again.


The asymmetrical spinnakers can be made in a variety of sizes. Some owners want these fairly small to avoid getting caught overpowered and some want to go big. On your size cat, I would guess an asymmetrical can be from 1,100 sq. ft. to over 1,600 sq. ft. 0.

I'm still ruminating on this, but this one issue is stuck in my craw....


What dimensions would fit on my boat and be 1600sqft?

Can you describe your reasoning/derivation of the numbers above, I'm having a hard time figuring those out...

[davecalvert]

Mainisland, It is easy to make spinnakers very different in sizes. This not only depends on the three side dimensions but the girths. First, some owners want room under the spinnakers for visibility and others want a maximum luff length. The profiles can be fairly triangular, with little area outside of the straight line luff and leech and others over 100% mid girth to foot length.