How many hulls ?

Hi,
I'm a newbie, just building a little skiff to learn to sail in.

Thinking ahead.
I'm planning on a small trailer sailer - take the family out for day trips or picnics, maybe some weekend trips with the wife.

Trouble is the family are a little apprehensive about sailing (or my abilities )
They say they'd be happier in a catamaran because (they think) they are more stable.

I thought, that makes sense, seemed logical.

There is a very good, active, yahoo group for Jarcats, which seem like a good option for a small home built family multi-hull. Trouble is, they all seem to tip their boats over, often more than once, and they are a bugger to right again.
Maybe they are just more experienced sailors pushing their boats to the limits?

Anyway, my question is, is a multihull really a more stable option for a novice sailors than a mono?
Biased opinions welcome, just tell me which way you swing (figuratively speaking).

Cheers

Simon.

 

Multihulls in the smaller sizes are wet, wet boats. They do not need to capsize to make you look like you did.
Some monohulls are wet boats too, but many more are dry, whole season boats that you sit down in.
Stability is a function of crew placement on any small sailboat. The most important thing to tell your family is that everyone takes part in the operation of the boat, and those who don't will be in the way like so much dead weight. A multi is stable at rest, but they carry a huge sail relative to their weight and hence crew weight is less effectrive on them. In other words, they demand more skill to stay upright in a real breeze no matter how wonderfully flat they sail in modest winds.
The monohulled daysailer is not prone to digging in the leeward bow and tripping on it. Most importantly the monohull usually has lots of space to stretch out and room under the boom to switch sides easily.

 

Alan
Thanks for that, guess that was the conclusion I was coming to but it's good to know for sure, and why.

I can see how repositioning would be easy on a monohull, but I'm surprised you say they have more room to stretch out. The Jarcat I was looking at http://members.optusnet.com.au/rhturner1/j5-6.html looks quite roomy for a small craft (6m).
I loved reading about Charlie Fisher [NIS23] in AABB, but it really didn't look like there was much leg room in the cockpit?

Guess I'll start looking (plenty of time) at designs of monohulls that are stable family friendly designs.
From things I've read a flat bottom, straight sides makes for a stable hull?
Or am I mixing 'stability' with 'tippy'? or are the two inextricably linked?
Is a hull that 'bobs around a lot' more or less likely to actually go beyond it's recovery point?

 

Usually, the small cat is a Hobie 16, which has a big trampoline with lots of space. The problem is not acreage per se but comfortable lounging space. Spend some time aboard one and you'll see that it's almost impossible to do anything but hang on. This is great for those who relish the speed potential of cats, but what about keeping the wife and kids happy? You need a place to stow a picnic basket or a thermos.
A daysailor can have a lot of usable room, and usable room is what I meant.
You mentioned the flat bottom type and the subject of stability.
Small sailboats, even keelboats, depend on crew weight to counter heel for the most part. Therefore, the differences between flat bottom types and round bottom types isn't so much about stability, but more about speed potential and handling characteristics.
A flat bottom boat pointy-bowed boat is generally called a skiff, and such boats are initially very stable. They sail okay, but also row and motor okay as well. This may appeal to you.
Round bottom types tend to sail somewhat better as a rule, as they have less hull friction. This makes them faster at lower wind speeds though both types are equal in heavy winds.
Multi-chine types fall somewhere in between, and if you build them, they are great examples of "most bang for the buck".
A good place to start if you are taking the family along, is a circa 15-18 ft centerboarder, either round bottomed (Daysailer 17) or multi-chine (Wayfarer), or even vee bottom (Point Jude, 19 ft Lightning class).
Flat bottomed boats are not so common any more, so you won't see many in glass in the size range mentioned. Not that they aren't good boats, just that the other hull types sail better in general (then again, Phil Bolger has made a career out of proving that box midsection boats are fast and faster than many more sophisticated shapes. To my thinking, they are ugly and structurally weaker than rounded shapes, needing more bulkheads, frames, stringers, etc..

 

One reason I look at flat bottom boats is that I live close to Morten Bay, S.E. Queensland. Pummicstone Passage in places has on 8~12 inches of water at high tide, but you may get to see a turtle, dugong or even dolphins.

Also you can beach a flat bottom for a picnic or afternoon on the beach. I'd like to visit some of the popular lake areas too.

If I can find plans for something not to complex, or expensive, I'd prefer to build out of ply myself. It's taken me about 8 months to build an 11ft skiff that other people have built in a week or two - I'm enjoying the process, what can I say. Building a boat might just turn out to be as much fun as sailing it.

 

There are loads of great skiffs in the 18 ft range, usually old designs. Check out WoodenBoat plans.
nice thing is skiffs don't need much for plans. You need some drawings, but a skiff kind of builds itself. I suggest you check out Bolger stitch and glue designs for complete plan packages.
You can easily beach any small boat that doesn't have a deep keel, however. A larger boat might benefit from a flat bottom, but all small boats will be relatively flat underneath.
But for simplicity's sake, yes, the flat bottomed boat is easiest to build. As said, it is structurally weaker that a vee bottom or round bottom boat (hence a bit heavier all things being equal). But cheap and ultra simple to build, shoal, etc..

 

There are also some (few) catamaran, or trimaran designs that have been designed to be more "family friendly." They are made to be drier, have more room, and be easier to keep upright than the Hobie style cats. The tradeoff, however ,is that they're not nearly as fast as their wetter siblings. (check out "Slider" for a decent example). If you look in the "Where are all the catamaran Innovations" thread, there are a couple posts (and a pic) from the designer of "Slider."

Also, in MANY situations, you can make a cat with better shoal draft than a mono...while still keeping some of your lateral stability

 

Thanks again guys.

Alan, I have looked at some Bolger designs and even though I know little about boats I understand that they are well designed, and highly respected, but do I really want to go sailing in a cross between a clog shoe and a coffin (no offence intended).

Rob, good to hear a pro-cat view point. I'm still worried that they have a penchant for tipping over though. If I do go for a cat the Jarcat (see link a few posts up) is small, enclosed, easily built and trailed - they say. The designer lives within an hours drive of me and there are probably 15 or 20 being sailed or built within the same radius.
I read a lot on Jarcat group on yahoo, which is quite active - they do tip them over regularily though.
Is that likely to be a fault of the design, or just the way they sail them?

 

Two BIG contributing factors to boats "tipping over":

1: Too much sail...and boat that's made with max. sail area for max speed is going to tip over...REGARDLESS of the design.

2: Sailing "on the edge." If you have too much sail up & pull the sheets too tightly, you'll be in for a spill. Any boat you choose, will be a LOT more "stable" if you use smaller sails..then you'll be less likely to tip it...but you can't go as fast.

 

..and that applies to mono hulls as well as multi hulls?
Mono's look a lot easier to get back right-side-up again too.
I do stress that I have no intention of 'sailing on the edge', or even going fast, but I am concerned about 'dumb novice syndrome', because I will be one.

 

With either style boat, you will gain more "experienced stability" by reducing sail area. The most major difference between multihulls & monohulls for what I perceive to be your purposes, is that multihulls have extremely high righting moment (stability vs. capsize) intrinsically, whereas monohulls need some form of ballast (lead, water, steel, whatever). End result: Multihulls generally stay "flatter" on the water, and follow the movement of beam waves faster, while monohulls tend to rock more and need more draft for weighted keels (though some use water ballast instead for shoal draft).

I hope I've cleared up more than I've muddled here for you

 

"Alan, I have looked at some Bolger designs and even though I know little about boats I understand that they are well designed, and highly respected, but do I really want to go sailing in a cross between a clog shoe and a coffin (no offence intended)."

There are some georgious Bolger boats. In addition to his boxy boats there are real knock-outs. Look again.

 

Yes, I was a little flippant there, I've also been looking an Jim Michalak's designs, simple construction is one of my requirements, I was seeing box shaped boats everywhere.

I have looked at Bolger's other designs and I do LOVE the look of his Light Schooner, not what I'm looking for, but really good lines.

I apologise unreservedly.
It's purely asthetic, and the designs do grow on you the more you look at them.

I've also stumbled across the Vacatoner & Weekender, don't know how they would fare in Morton Bay, but they look really good, though I don't think they have the simplicity of construction I require.
Today I was looking at Michalak's AF2 and Normsboat. Again, don't know how they would perform in the bay or on coastal waters, or if they are just flat water boats - they quite light? They seem to use half the materials of, say, his Picara, which to a novice looks very similar.

 

Those are simple sharpie hulls. Light and fast, but usually lacking self-righting ability. They don't sail well heeled over, preferring early reefing, but the construction is simple and the shoal draft allows beaching and sailing in shallow places. They make a good first build.
All good boats for near shore sailing.

 

Michalak has some similar designs that are multi-chine, but otherwise similar specification - gee's he seems to have nearly as many (though not as varied) designs as Bolger.

The multi-chine (Bobster, Fatcat, Toon2) ones look like they may be a little more complex to build, but maybe they are a little more forgiving on a novice sailor, or a little less scary to be in?

I did. If my first build is a Michalak, my second might just be a Black Skimmer.
http://www.nexusmarine.com/skimmer_home.html