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  #11  
Old 05-16-2008
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I suppose from a cruiser's point of view, the first criterion might be price - how much boat do you get for your money - then volume - how much can you stuff into it and still move around. Then having bought and stuffed it, how well does it now sail?

My impression is that for the price of a Dragonfly 1200, I could buy a lot more volume in a monohull, or conversely, the max volume loaded in the Dragonfly would slow it down a lot. On cats, if I filled them to their volume, they might sink.
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  #12  
Old 05-16-2008
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As a multihull sailor and owner I think single handing is easier on multi's due to the more stable nature.
I have no qualms at all going forward and doing work while letting my autohelm mind the boat.
I've only truly singled my own Gemini (33.5 feet), but I've sailed up to 42's with crew that was racked out doing nada, no problems.

It's also (due to the dual engines) much easier to dock a multi when alone.
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  #13  
Old 05-16-2008
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I'd think that a generalized rule for multihulls isn't really all that feasible, since there is such a wide range of variation on the designs...

First of all, you have two distinctly different platforms—catamaran or trimaran.

Second, you have very different design philosophies... on a trimaran, you can have a full wing deck design like an older Jim Brown Searunner, a partial wing deck like some of Dick Newick's designs, or a center hull only design, like Chris White's Hammerhead 54.

Same thing on catamarans... you can have a relatively minimalist catamaran with little or no bridgedeck ala Wharram's Tiki series, or you can have a low-bridgedeck clearance, high windage beastie with a nearly complete solid bridgedeck, like an endeavorcat, or a high-performance partial bridgedeck boat like a Gunboat 48.

For example, while a Gunboat 48 may have a fairly high cabintop, it is located fairly far aft on the boat, and doesn't affect the boat's ability to tack.

As to where to draw the line...it really depends on the boat, the way it is rigged and the sailor. Larger boats, by definition, are more capsize resistant and safer... but a boat that is too large for you to safely handle is just as dangerous, if not more so, than one that is too small.

I wouldn't buy a multihull that is under-canvassed. IMHO, this is a problem with some of the cruising catamaran designs out there... since they come with a relatively small sail plan. The problem with that is the majority of the time you're out sailing, you're generally in lighter winds, say 5-15 knots. With a deliberately under-canvassed sailplan, you'll have to motor in the lighter winds. That is probably why you see so many large charter cats motoring, rather than sailing.

You really need to have sufficient sail area to move the boat in light winds, yet have the ability to reduce sail down enough so that you're not over-canvassed in higher winds. In some cases this may be accomplished by rigging the boat as a cutter or ketch, rather than a sloop. It may also be accomplished by having more reefing points, say three instead of two, or deeper reefs that eat up more sail area with each reef. In fact, I'm thinking of asking my sailmaker to add a third reefing point to my mainsail for just this very reason.

While a multihull can have an impressive speed advantage over a monohull, especially over short distances, the overall speed advantage over long distances and durations isn't as great as most people would think. This is often due to the fact that you don't want to sail a multihull at the maximum speed it is capable of in most conditions, since that is a good way to end up pitchpoling or capsizing her. I've been out in 30 knots of wind, and I could have probably gotten my boat going at 17 knots or so... but generally, we'll sail at 9-11 knots instead. The ride is much more comfortable, the boat is under much less strain, and the risk of pitchpoling or capsizing is much, much lower.
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  #14  
Old 05-16-2008
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Chuckles, those are good points. Maybe I've just forgotten how difficult it was to single-hand my old Pearson mono-hull. The wide, flat deck of my Gemini is easy to work on. And the boat mostly wants to go straight, even without an autopilot. (Unlike my Pearson, which wanted to do donuts in the water when I went forward.)

And docking is a lot easier. Unlike a mono-hull, my cat is just about as easy to steer in reverse as in forward.

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  #15  
Old 05-16-2008
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I never backed my mono hull in well, just too uncoordinated I guess. I gave up trying after a while.
The first time (my after purchase demo sail) I brought my Gemini back in I backed her into the narrow (17 ft for a 14ft beam) like I'd been doing it all my life.
Will H at PCI was onboard and remarked that it was the best he'd seen in a long long time - the guy in the slip next to me said he wished he could do it that well.
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Old 05-16-2008
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I'd have to agree... we've been out in heavy winds and while we're sitting in the cockpit, passing the chips and soda around, we'll pass a large monohull sailboat and their crew will be hanging on for dear life, and in full foulies...getting soaked... LOL...
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You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

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Last edited by sailingdog; 05-16-2008 at 01:31 PM.
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Old 05-16-2008
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Nautig and Chuckles, thanks for chiming in!

Sailingdog, "undercanvassed" was a poor choice of words on my part. I should have said 'reefed down', 'sailed conservatively' or something equivalent.

The comparison I was trying to make was between a multi-hull sailing conservatively at 9-11 knots and a monohull straining all limits to reach equivalent speeds. I was imagining my sailing friends who expend enormous energy and inordinate amounts of cash to make a mono-hull 'go-fast' and thinking, "why don't they just sail a multihull".

Your point that multihulls don't necessarily average high speeds over 'long distances or durations' is well taken. But what about 'normal cruising' where you may have flexibility to choose advantageous weather? Does the 'weekend warrior' enjoy higher average speeds over his monohull brethren?

If a 40' catamaran sailor can comfortably acheive 9-11 knots, he may be doing better than the trawler converts! Are catamarans the potential non-fuel alternative for the trawler crowd? Interesting prospect.

Thanks for pointing out the different design parameters, bridgedecks, windage, etc. Obviously, they are crucial to the discussion.

Personally, I'm more attracted to Catamarans, but I've admired two Tri's in our area. I like Chris White's designs, but I'm not qualified to judge them. I studied a Wharram also and was impressed with the practicality. Floating condominiums don't interest me, no matter how they're packaged.

Given the parameters we're discussing, which 35' ish to 40' ish Catamarrans or Tri's should I study as 'best of the breed'?

Thanks to everyone for your help!

Piscator
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  #18  
Old 05-16-2008
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Think of a multihull as a sports car.... yes, they can do 120 MPH
Wow, that is one fast boat.
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  #19  
Old 05-16-2008
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Yes, the weekend warrior or coastal cruiser does benefit from the higher speeds a multihull can sail at. A well designed 40' catamaran can probably sail at 15-17 knots fairly comfortably, given some decent wind. My example of 9-11 knots is on a 28' trimaran.

The only problem with Chris White's designs is that most are one-offs and not production boats, and judging the build quality and production quality is a bit more difficult.

When I was looking at boats, I was interested in getting one that had decent sailing characteristics, yet could be trailered, since some of the sailing areas I want to get to are effectively landlocked. Lake W. in NH is one example. Besides, not many boats can go to windward at 60 MPH. Most of the smaller catamarans don't sail as well as the trimarans in the <30' range.
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You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

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  #20  
Old 05-16-2008
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Gemini (105Mc and even 3400's for the older ones) are of course the best of breed when one considers price, performance (regular 10kt days, 18kts achievable) and features (queen sized bed, air conditioning, fits in a commonly found 15ft wide slip).
Charles Kanter's Cruising Multihull Communique said it best. Gemini's are the best value for the buck out there.

They do have their problems, quality control issues and shortcomings. The Yahoo group (over 1300 members with and without boats) talks extensively about the boats, improvements etc.. In fact the yahoo group is the best FREE feature of the boat.

Disclaimer: I'm somewhat biased. I've had my Gemini one year this week.
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