Characteristics of a Circumnavigating Cat

[kcrane]

Originally Posted by Llamedos

We have the first BB42 that was built in 2003. I can confirm that the 435 is exactly the same as the original 42 with the addition of an extra length step/bathing platform to the transoms to give the 43.5ft length.

Amazing what you can work out when you collate lots of small pieces of information!

[Intentional Drifter]

If you are considering used boats for a circumnavigation, I suggest you also look at Prouts, particularly the 45/46. They are an "old" design, but also one that has been successful. In actuality, the current BB 42 and 38 were originally Prout designs that were going into production when the company went under. There are a fair number of 45/46's available in the used market for prices well under current new boats. They are spacious, well-constructed, seaworthy boats. (Note that this can't always be said for some of their other models.) You might want to check out: New Home for the history and cruising logs of a 45 that did a circumnavigation.

While people continue to focus on speed, the best data available indicate that when in cruising mode and loaded, there simply isn't much difference. The vast majority of cruising cats will do around 7 to 8 knots, in typical downwind conditions, most of the time. This seems to be true whether "light" or "heavy", 38' or 45', daggerboards or keels, etc. This was true for Cosmos, even though this boat that many would call a "slug" also turned in a number of 200+ days.

ID

[Stella Polaris]

Originally Posted by Intentional Drifter

While people continue to focus on speed, the best data available indicate that when in cruising mode and loaded, there simply isn't much difference. The vast majority of cruising cats will do around 7 to 8 knots, in typical downwind conditions, most of the time. This seems to be true whether "light" or "heavy", 38' or 45', daggerboards or keels, etc.

I agree about the speed focus. I'm starting to keep an eye on light wind performance. It's a huge advantage to be able to sail when others have to motor. The heavy cats will be at a disadvantage, because in some cases, they need a lot of wind to move.

When I was sailing in the Med. the joke was always: Either there is not enough wind, or you've got too much.

If it's very windy and choppy we tend to stay in the protected anchorages, but on days with little wind it would be excellent to be able to hoist the sails and still be able to make some headway without using the engine.

[OldYachtie]

Balsa is used by quite a few highly thought of boat builders: Alerion, Alden, Beneteau, J-Boats, Contest, Cabo, Sabre, Tartan, Catalina, Hunter, Morris, Santa Cruz, the Deerfoots, Waquiez, F-Boats, etc. Lots of Australian boats are being made out of Duracore, which is a commercially available sandwich material with balsa in it. Of stock catamarans, Lagoon (made by Jeanneau,) Prout, and Africat use balsa. The SCRIMP TPI built boats use balsa.

Some of the more convservative builders use balsa only above the waterline, in case collission causes punctures that could lead to water penetration below the waterline.

As has been mentioned, some foams used for cores can be attacked by styrene, the "thinner" in polyester resin. Also, balsa is stronger than foams usually used for cores. Some foams sag when heated by tropical sunshine, so balsa is often used in decks. The better boats, in fact, often use balsa and vinylester. You will see a lot of balsa, vinylester, carbon, and e-glass (the expensive, stronger glass,) being used together if you google "balsa vinylester."

Foam cores are lighter than balsa, so you see them used in more catamarans. With the high oil prices currently, foam costs about twice as much as balsa, so economics argue in favor of balsa. What of longevity?

Well, I finished out a boat in the early seventies which I sailed across the Pacific (Batwing,) and which circumnavigated subsequently under new ownership, had a balsa core deck. It is still going strong, and is in central America, having recently sailed there from Bellingham. I was on Batwing a couple of years ago, and everything was still as I had built it, except for cosmetic changes.

So, some 30 odd years of hard cruising later, it is still fine. Decks are full of holes, and Batwing's certainly were, and I didn't use inserts of other materials where I bolted stuff to the deck-just plywood backing plates under the deck. So, I don't think balsa can be so very vunerable to water damage.

Tim Dunn
near Seattle

[schoonerdog]

Balsa is stronger than many foams and is used in many cats which otherwise would choose a foam core for certain high stress areas which are prone to flex, the PDQ 44 is an example which used foam cores for their hulls and decks but has some areas of balsa under the bridgedeck. Actually at 700k a pop, PDQ doesn't scrimp on anything they choose and use a variety of cores depending upon the location. Tartan is another boat builder who produces some of the more expensive but better built boats and "In the fall of 2002, Tartan advanced the art of boat building by constructing all of our hulls from a composite of uni-directional E-glass reinforcement and Core-Cell linear polyurethane foam core bonded with epoxy resin. This decision created the new standard for quality, high-performance hull construction." Previously they had used balsa.
It's not that balsa is bad, but it should be thought of in terms of its advantages (strength in certain areas) and it's disadvantages in the potential to rot and extra weight, and some of the very best ones have both. If people wanted pure strength, they wouldn't get a catamaran, they'd get a massive steel monohull. People typically choose cats because of their stability, layout, potential for positive flotation, redundant critical systems such as motors, and speed to reduce weather windows.

[44'cruisingcat]

Actually even though balsa is heavier than foam, if it's used properly you can build a lighter boat. Balsa is a little less than twice the weight of foam, but has more than twice the sheer strength and more than 3 times the compression strength. So you can achieve the same panel stiffness with a thinner core or laminate (or both)

Balsa can rot, so care has to be taken with any penetrations to drill a larger hole and seal the core but really that's something you would be advised to do with a foam core anyway.

[OldYachtie]

Corecell is said to be nice stuff, and the most resiliant in case of impacts such as collisions. I got my information about who is using balsa from a quick survey of the web, and I am not surprised that some of it might be dated. Another name I came up with for balsa users is Outremer, makers of light-weight catamarans. Regarding weight, balsa and foam both come in various weights. Gerr's book on scantlings specifies either 9 to 10 pound balsa or 8 pound (per cubic foot) foam for workboats, for example. The weight of foam usually used in medium size yachts is 6 pounds per cubic foot, however, and balsa weighing less than 9 pounds per cubic foot is a premium product compared to 9#, though I don't know its specific pricing. Anyone specifying balsa should specify precoated, as the ultimate product will be much lighter than that primed by the builder. Balsa is now avaialble "perferorated, grooved, and precoated for infusion.

I am working on a large catamaran design right now, and I intend to use balsa in the topsides and decks, but I will keep the decks solid glass near the hull-deck joint, so that highly stressed items such as railings and mooring cleats are in solid GRP.

[schoonerdog]

Outremer uses 20mm PVC foam for their decks and major elements, though like PDQ they probably use balsa for high stress areas. Also, some items like divinycell come in several different formulations depending on the density and strength required (submarine, aerospace, low temperature, high temperatures). 44 cruising cat is right, our boat has divinycell and I'm going through and sealing the cores as I'm doing regular maintenance items like rebedding hatches and deck hardware. Obviously, either material can be used well. It would be interesting to see though the specific benefits of the different types of foam.

[Gordon]

Hi again SettingSail2009, sorry for the long wait for a reply,have been waiting on the info from the factory. They advise that bridge deck clearance is 80cm. they were unable to tell me the hull/beam ratio. As to the sunbed layout, it makes use of deck area above bedroom,keeps sunbather in rear cockpit area, not too sure how it will fit into the scheme of things under sail ! The latest is first boat into water mid June , no actual delivery date on our boat #4 yet. Australian agent visiting factory next week. Gordon.

[GordMay]

Originally Posted by Gordon

... They advise that bridge deck clearance is 80cm. they were unable to tell me the hull/beam ratio ... Australian agent visiting factory next week. Gordon.

I suggest you give your agent a tape measure.

[The_Bean]

Hey SettingSail2009.

You mentioned a whole list of specs earlier and were wondering if you could get them all. I think you will be able keep them all and have a few extra that you were not expecting

Check out these specs.
A brand new 38' starting at about US$220K for a sailaway.

[Stella Polaris]

Originally Posted by The_Bean

Hey SettingSail2009.

You mentioned a whole list of specs earlier and were wondering if you could get them all. I think you will be able keep them all and have a few extra that you were not expecting

Check out these specs.
A brand new 38' starting at about US$220K for a sailaway.

Hey, I had a look at the Admirals but I found the forward view from inside is a bit too restricted for my liking.

I also get the impression from the Admiral website that it's not meant for circumnavigating:
"This version of the original 38ft. model retains many of the indispensible features of a luxury craft and suits short trips where costly extras such as desalination and airconditioning are not required. The finish is rugged enough to sustain frequent use and the sailing characteristics are excellent."
The words in bold make me think that it's more for weekend and holiday cruising, as opposed to full time circumnavigating.
You own one, so you might be of a completely different opinion. I'm very curious what you think.

[Stella Polaris]

Originally Posted by Gordon

They were unable to tell me the hull/beam ratio.

Hi Gordon. I've gotten the same response a few times. When I asked the Leopard dealer, he had to get a guy out in a kayak to measure the BD clearance. As to the hull/beam ratio: he said he'd have to get in touch with Morrelli and Melvin (designers) to find out ... He still hasn't gotten back to me.

Originally Posted by GordMay

I suggest you give your agent a tape measure.

I think they need more than a tape measure ... A clue about what to measure is probably a good beginning.

[The_Bean]

It just looks a lot smaller on a photo. I am 6'3 and I find it very spacious. The only place that I battled was in the head on the 4 cabin version, so I ordered the owners version and now have a huge amount of room. We searched long and hard before making our choice. Ware going to be circumnavigating starting in Jan 2008 out of Cape Town following the trade winds. There are quite a few others that are busy circumnavigating in Admirals at the moment and all seem to be happy... put it this way... I have heard no negatives. Yes there is a lot of luxury and it is extremely well finished etc. but don't let that fool you... under all the pretty things it is a tough boat. We have added everything we need and then still a few extras to make our sailing life as comfortable as possible. I figure why not... we have worked hard enough.

Admiral also make a 40 and a 50ft version, if the 38 is too small for you, but the 38 is more than ample for 6 people... AND it's just going to be the two of us doing the sailing.... which suits us!! The kids can come and visit from time to time and at least there will be a bunk for them.

[Desert Sailors]

Post #77 From Cesar: Courtesy of Babel Fish Translation site for those of us that don't read or speak spanish.

Hello Andreas: What attempt to say is that a catamaran of 12 meters seems to me a little right to cincumnavegar. The lowest charge that tendras that to put in your boat (including fuel, water, viveres, personal effects and navigation equipment) will be of 2,500 kg; reason why in a catamaran of 12 meters you will go to limits of its capacity. Of course that depends on the budget that is arranged to the purchase of the boat, but from 43 or 44 feet, I believe that it is where the options of a catamaran with which begin to give the return to the world. I, bought in 2003 a Lavezzi 40 (FP's); my intention was to equip it to give to the return world. But I have seen a little it just; I do not mean with that it is not been worth to cincumnavegar; the boat is very good, resistant, comfortable, easy to sail, etc..., but to live years in a boat, you consider to equip it with a series of comforts which you enjoy to newspaper (and if you can, porqué to resign to them); then you think about the electrico generator, the desaladora, the conditioned air, extreme etc... and if everything what they weigh (besides to look for a site to him to place them) what before it seemed sufficient to you, now you begin to see it a little little. Really, the desición that I have taken has been to sell my Lavezzi 40 and to buy a new Salt mine to me 48 (also FP's). Until March of 2008 me they will not give it. To load Salt mine 48 with 3,000 or 3,500 kg does not suppose to put to limits the capacity of this catamaran, because it admits a load of 4,500 kg; with which its operation will not be seen it jeopardize. Here, in Spain, the shipyards of catamarans that but are seen are the Lagoon and the Fountaine Pajot; in the less measured Privelege. Of the Catana I do not say anything because its price has not allowed me nor so at least to think about them. I believe that, of these shipyards, there are several models that are adapted to cincumnavegar. From a Belize 43 to a Privelege 495 perhaps (this he is a little expensive) you have enough boats where to choose. Much luck in your decisón. A greeting. Caesar.