My Multihull Rigging Thread

[smj]

I would sail the boat with the sails that came with it to get the feel for what you’ll need, pretty sure this is your plan anyways.
We used the screecher a lot on both our Seawind 1000 and Searunner 38 and thought a bowsprit and screecher upgrade would be in the works on our TRT. As it turns out we really haven’t felt the need for the screecher on this cat. She has enough performance with the high roach main and 110% jib. We do have an assym that hopefully we will finally try out at some point!

[Chotu]

Originally Posted by smj

I would sail the boat with the sails that came with it to get the feel for what you’ll need, pretty sure this is your plan anyways.
We used the screecher a lot on both our Seawind 1000 and Searunner 38 and thought a bowsprit and screecher upgrade would be in the works on our TRT. As it turns out we really haven’t felt the need for the screecher on this cat. She has enough performance with the high roach main and 110% jib. We do have an assym that hopefully we will finally try out at some point!

that’s definitely the plan. I don’t know how much life is left in these sails. They are pretty crispy. But there’s some restitching that is needed.

No high roach main here.

Just a pinner. Lol triangle top.

when the mainsail is shot I will definitely be upgrading to a better one.

but for now I’m just using the rig. As it came. Just like you are suggesting. With the addition of the spinnaker.

[Tupaia]

Originally Posted by smj

I would sail the boat with the sails that came with it to get the feel for what you’ll need, pretty sure this is your plan anyways.
We used the screecher a lot on both our Seawind 1000 and Searunner 38 and thought a bowsprit and screecher upgrade would be in the works on our TRT. As it turns out we really haven’t felt the need for the screecher on this cat. She has enough performance with the high roach main and 110% jib. We do have an assym that hopefully we will finally try out at some point!

Another vote for a mildly overlapping jib.

[Chotu]

Originally Posted by Tupaia

Another vote for a mildly overlapping jib.

Except I'm not buying new sails until after I use the boat.

I think I can live without the 10% this summer.

I'm sticking to the plans and the typical setup fot similar boats these days.

For now.

I have a moment finally. I'll get those numbers

[Chotu]

Originally Posted by Tupaia

Does KH not give any idea about the dynamic stability?


Give us some idea about what we are dealing with what is the CL beam, mainsail area, mast height, for-triangle, weight, Any idea where the CE for various sail combinations and CLR will be?

Fore triangle base is 14.5ft from the bow beam (not sprit).

52ft along the Furler up to the fractional rig attachment point from the bow beam.

Blade area is 362 square feet? hoping my math is correct.

CL beam is 19.5ft

Mainsail foot is 20'6".

Mainsail luff is approximately 57ft

Mainsail area is 585ft. because it’s a triangle top. Looking to upgrade to a full roach main when this one is done.

Mast length is 64ft, stepped on deck around 6-8ft up from the waterline.

Boat weighs around 6 tons with no rig. but who knows final weight?

Max displacement is 9 tons.

what can you glean from all of that? I got you all these numbers. What do they tell you?

Center of effort versus center of lateral resistance? That was done in the design stage by the designer. I’m not sure why we would we be discussing that. That’s something that is done when the boat is designed.

Center of lateral resistance is where my boards are. Unless they are up it might change a little bit. Slightly aft of the mast. By about 3 feet? I don’t see where that is taking us.

[s/v Jedi]

Originally Posted by Chotu

Wow. I never looked closely at your boat model.

That's a nice lean machine with a ton of sail area.

I can see why you're fast. Not a lot of wetted surface area for so much boat and sail.

Here’s a good picture of the hull shape. It is obvious that Steve Dashew has a multihull background: the rig is like a multihull (no backstays) and even the hull looks like it is one side of a catamaran. We’re 64’ long at the waterline but only 16’ wide.

We actually have little sail area for the size boat, but we don’t need much to make speed (easily driven they call it). We do 4 knots in 7 knots true wind and that is with working sails incl. the 95% jib

The other picture is an old one when we were only minutes ahead of a violent squall and just lowered the main(still doing 9 knots without the main!), preparing to anchor in Bequia before the squall hit us (we succeeded with seconds to spare ). It shows the big roach of the mizzen, which has a sail area that is 78% of the rectangle formed by mast and boom. Compare that to 45% of those in-mast furling things

That was a tri-radial laminated sail, mildewed and delaminating and I replaced it with a tri-radial made from woven HydraNet. I think my next sail will be one of those 3D molded ones

[Chotu]

Here is the sail plan, Tupaia:

Attached.

Centers of effort and lateral resistance included.

[Chotu]

Originally Posted by s/v Jedi

Here’s a good picture of the hull shape. It is obvious that Steve Dashew has a multihull background: the rig is like a multihull (no backstays) and even the hull looks like it is one side of a catamaran. We’re 64’ long at the waterline but only 16’ wide.

We actually have little sail area for the size boat, but we don’t need much to make speed (easily driven they call it). We do 4 knots in 7 knots true wind and that is with working sails incl. the 95% jib

The other picture is an old one when we were only minutes ahead of a violent squall and just lowered the main(still doing 9 knots without the main!), preparing to anchor in Bequia before the squall hit us (we succeeded with seconds to spare ). It shows the big roach of the mizzen, which has a sail area that is 78% of the rectangle formed by mast and boom. Compare that to 45% of those in-mast furling things

That was a tri-radial laminated sail, mildewed and delaminating and I replaced it with a tri-radial made from woven HydraNet. I think my next sail will be one of those 3D molded ones

That boat is a BEAST!

A perfect monohull. Love it!

I also don’t know where I forgot that the Dashews had something to do with those. I had thought it was some other marketing name they used. I didn’t even realize this was their design. those designs always made a lot of sense to me.

Everything about that boat looks perfect to me.

[sailingharry]

Originally Posted by s/v Jedi

That was a tri-radial laminated sail, mildewed and delaminating and I replaced it with a tri-radial made from woven HydraNet. I think my next sail will be one of those 3D molded ones

Our main is over a decade old, with two transAtlantic's behind it. Tri-radial HydraNet. Love that sail!


Our jibs are 3 year old North 3DI Nordac, a 3D molded 100% dacron fabric. 3 years and 7,000 miles on them. Love those sails!


Note that the 3D molded sails are VERY stiff. They work wonderfully on a roller, but I can't imagine the material in a stack pack. Maybe on a Dutchman. Probably OK on a bolt rope mast, where it is then flaked across the boom like racers do.

[fxykty]

Originally Posted by Chotu

Here is the sail plan, Tupaia:



Attached.



Centers of effort and lateral resistance included.

The attached plan doesn’t show the full sail nor the individual reef areas, so forgive me if my assumptions are wrong. I’ll also throw some other thoughts out based on some other responses in this thread.

The reefs look really small, particularly 2 and 3. If you don’t plan to use a trysail then you want your 3rd reef to be less than 50% luff height and less than 40% of full sail area. The head at each reef should be at a strong point of the mast, though if your mast has 3-point diamond shrouds that’s less critical. Typically reef one puts the head at the hounds and will be your go-to - we use our 1st reef about 50% of the time.

You can build your own reefing plan empirically - basically at the top of each step (particularly from one mainsail reef to the next) the leeward cap shroud goes soft and the windward hull lowers its waterline by 5-10cm. Otherwise, if your rigger can provide force calculations for all of your sail areas then that can be a starting point.

As other have said, and yourself, sail with what you’ve got until you’re sure you know what you need as you replace the original sails. I expect the mainsail, likely most expensive, will be the first to replace. You’ll want as big a roach as possible as either round top (simplest) or square top (marginally more area up high but more complex halyard/mast connection).

Your rigger doesn’t like the symmetrical spinnaker because he knows racing boats that sail the angles. That’s not you. For cruising, DDW with a symmetric and no main is easy, comfortable and relatively fast for little effort (we sail 50-60% of TWS in this configuration).

We have a self tacking jib that’s about 95% of fore triangle area. We are underpowered upwind below 7 kts TWS; after that no problems. We’ve thought about building a small screecher that would fit inside the shrouds but in our 6 years of ownership we just haven’t felt the need (we just accept that we’re going slower than what is possible). Our large screecher (160% of our mainsail area) can sail up to 40* AWA, but with the speed it generates we’re actually going 80* TWA; great for reaching and medium air running, but too big for upwind. It gets furled when the AWS gets to 15 kts (sometimes when running we’ll keep it up longer) and by that point the self tacking jib is fully powered with the wind strength.

If you think you might want an overlapping genoa in the future then you can use floating sheet leads that only require hard points and not tracks. Basically you just need to ensure that you can lead a sheet to a winch without too many corners.

[s/v Jedi]

Originally Posted by sailingharry

Our main is over a decade old, with two transAtlantic's behind it. Tri-radial HydraNet. Love that sail!


Our jibs are 3 year old North 3DI Nordac, a 3D molded 100% dacron fabric. 3 years and 7,000 miles on them. Love those sails!


Note that the 3D molded sails are VERY stiff. They work wonderfully on a roller, but I can't imagine the material in a stack pack. Maybe on a Dutchman. Probably OK on a bolt rope mast, where it is then flaked across the boom like racers do.

Interesting, I have no experience with 3D molded sails but plan to use them for main and mizzen as well as the jib. We have fully battened sails and I have seen cats with similar rigs also use them for their main?

[sailingharry]

Originally Posted by s/v Jedi

Interesting, I have no experience with 3D molded sails but plan to use them for main and mizzen as well as the jib. We have fully battened sails and I have seen cats with similar rigs also use them for their main?

There are certainly a variety of molded sails, so we may not be talking the same one. The North product is not laminated, I consider that a major plus. As I understand the North product, they have a gun that takes glue saturated fibers and lays them over the mold, increasing the number of passes as/where necessary to get the required thickness. Like a laminated string sail, they lay the fibers in the direction of the load. They can also mix various fibers for different cost / performance results. Mine is 100% dacron, even meets racing rule bonus points for Dacron sails. I expect to have the inherent longevity of Dacron sails, but keep the performance significantly farther into the life cycle than woven fabrics. A major improvement over woven sails is the lack of stretch associated with the fibers straightening.

I am really sold on their product, the performance is amazing. But our jibs after 3 years and 7,000 miles have a consistency not unlike a plastic milk carton. A friend with one could not get it into a stack pack, but was much happier when he went to a Dutchman. Of course, a Dutchman would require me to reinstall the topping lift...

[s/v Jedi]

Originally Posted by sailingharry

There are certainly a variety of molded sails, so we may not be talking the same one. The North product is not laminated, I consider that a major plus. As I understand the North product, they have a gun that takes glue saturated fibers and lays them over the mold, increasing the number of passes as/where necessary to get the required thickness. Like a laminated string sail, they lay the fibers in the direction of the load. They can also mix various fibers for different cost / performance results. Mine is 100% dacron, even meets racing rule bonus points for Dacron sails. I expect to have the inherent longevity of Dacron sails, but keep the performance significantly farther into the life cycle than woven fabrics. A major improvement over woven sails is the lack of stretch associated with the fibers straightening.

I am really sold on their product, the performance is amazing. But our jibs after 3 years and 7,000 miles have a consistency not unlike a plastic milk carton. A friend with one could not get it into a stack pack, but was much happier when he went to a Dutchman. Of course, a Dutchman would require me to reinstall the topping lift...

You don’t address my point but it doesn’t sound like you and your friend have fully battened mainsails, which drastically changes this. I will try to learn more about the molded sails people with fully battened sails use, thank you

[sailingharry]

Originally Posted by s/v Jedi

You don’t address my point but it doesn’t sound like you and your friend have fully battened mainsails, which drastically changes this. I will try to learn more about the molded sails people with fully battened sails use, thank you

Indeed, your case may be different. My main is still Hydranet (and the bottom two battens are only partial), and I've never actually seen my friend's boat under sail. I have no real world experience with a 3D main, and I'm only advising due diligence. If it can be made to work, I would be an enthusiastic supporter, as I do like the product!

I am within 24 months of replacing my main, and the cost of Hydranet is stunning. I would love to hear feedback if/when you go 3D.

[s/v Jedi]

Originally Posted by sailingharry

Indeed, your case may be different. My main is still Hydranet (and the bottom two battens are only partial), and I've never actually seen my friend's boat under sail. I have no real world experience with a 3D main, and I'm only advising due diligence. If it can be made to work, I would be an enthusiastic supporter, as I do like the product!

I am within 24 months of replacing my main, and the cost of Hydranet is stunning. I would love to hear feedback if/when you go 3D.

Like you, my (2005) Hydranet sails are still in good condition so it won’t be anytime soon

I’ll start with looking at all the offerings on 3D molded sails and the differences