The Short List for Bigger Boat Itis

[Frank]

 Hull shape means so much.Different designs do different things well. A hull with a wide beam and firm bilges will have great initial stability,take a fair bit to heel her over,generally pound more in a seaway and once it starts to go over.....have very limited ultimate stability. A longer/narrow hull with slack bilges will have fair better motion in a seaway,have exellent ultimate stability , but will initially seem quite tender. All depends on intended usage.In my book...the Triton would be one of the best compromises for an inexpensive,comfortable sailing ,'offshore' type hull.

[Joe Pyrat]

Oops, sorry I missed those questions.

Going a little further, more modern boats are generally beamier than the more traditional boats.  They tend to be stiffer initially because of this wider beam.  The problem with some of these new designs is they can achieve stability when inverted, meaning they can roll over and not come back around.  More traditional boats like the Triton tend to return to the mast up, keel down position more rapidly. 

The beamier boats I've sailed on always seemed to have more difficulty maintaining their course, seeming twitchy when you are steering them.  This is more a function of modern keel design than beam, but is another function of more modern hull/keel design.  The Triton's full keel with cutaway forefoot lets her track very well like traditional full keel boats, but, unlike full keel boats, still turn fairly quickly.  Kind of the best of both worlds. 

I suspect broader beam monohulls may be a bit more impacted by chop too.  I sailed on a trimaran once and the port to starboard action of the boat due to waves coming beam on was quite abrupt.  I would think this might, to a lesser degree, be applicable to broader beam monohulls.  Boats like the Triton seem to ride fairly easily when receiving beam on waves.

Edit...
You beat me to it Frank...   :)

[s/v Faith]

I poured you both some grog so that me might toast Carl Alberg together.

  To Carl.....  ;D

[Frank]

To Carl it is !! ....Cheers !

[AdriftAtSea]

Part of the reason the motion on most multihulls is so abrupt is that the boats generally mass less, so they have a quicker motion than monohulls.  The beamier monohulls may not have the quicker motion, or at least to the same degree, but it depends more on the total displacement of the boat IMHO than the beam of the boat.

[Captain Smollett]

but it depends more on the total displacement of the boat IMHO than the beam of the boat.

The laws of physics are not opinions.  Stability curves and thus righting moments DO depend on beam insofar as the beam effects the distribution of mass.  Righting moment is based on intertia which is strictly speaking a tensor (a kind of hyper vector).  And we are not even considering the effects of waves on the boat (which complicates things tremendously since then we have to be concerned with the stress tensor as well).

Each term in the interia tensor has vectors that describe the distance from the coordinate origin (which for simplicity we can take as the center of mass).  So, total displacement IS important, but the distribution of that mass in space is ultimately what determines the motion.  Therefore, beam is a factor, and putting the mass in two hulls far from the center of mass is quite different than putting the mass in an equivalently wide single hull with mass more evenly distributed along the 'beam.'  You can construct our two hypothetical boats with the same total displacement, but the motion will still be very, very different.

Also, consider this.  A lot of mass located AT the center of mass will rotate (roll) easily; so it is possible for a heavy boat to be very tippy - if a large percentage of the total displacement is located near the center of mass (which will lie on the roll axis).  What makes a ballast keel work to yield righting moment is that it is 'offset' from the center of mass; as the boat heels, the ballast results in a torque in the 'go back upright' direction.

Hope this helps.  ;)

[Frank]

Way TOOooo much 'vectors' 'tensors' 'interia' and 'mass'for a real simple mind like mine. A great designer once said "if it looks fast and smooth , it probably will be". When you look at a 1/2 hull of an offshore design.....ya KNOW it's goin to be smooth in the waves. Do the same with a 'wide body/flat bottom' and ya just KNOW its going da pound !! Rocket science simply proves what your eye already tells ya.

[oded kishony]

>Rocket science simply proves what your eye already tells ya.<

I'm just an ignorant violinmaker, but for the last 5 years I've been learning the acoustical physics of the violin. I've been truly awed by the physicists and engineers I've worked with.

There are three basic types of minds, ones that can understand and integrate formulas and symbols, ones that have an intuitive grasp of how things work and mostly stupid people who can't do much of anything ;-)

The analytical and the intuitive mind very rarely inhabit the same body. In fact the analytical and intuitive often can't communicate at all with each other-often they just don't speak the same language. This might all be about right brain vs left  brain stuff.

Oddly almost every violinmaker I know also sails a boat.

oded kishony

[Cmdr Pete]

Who would have thought you could mix physics, sailing and violins?

[Captain Smollett]

Who would have thought you could mix physics, sailing and violins?

:) :) :) :) :) :) :) :) :) :) :) :) :) :) :) :) :)

Right on.

[Frank]

Old 'Albert' was an intuitive abstract thinker...he would day dream ideas and then set about proving them. A brilliant man..a top physics mind...and yet he had a very hard time making accurate change at the store !! He simply LOVED his sailboats and those close to him wrote of how he was 'most at peace' while sailing.

[Cmdr Pete]

"I am happy because I want nothing from anyone. I do not care for money. Decorations, titles, or distinctions mean nothing to me. I do not crave praise. The only thing that gives me pleasure, apart from my work, my violin, and my sailboat, is the appreciation of my fellow workers."

A. Einstein





"A little nookie would be nice too"

C. Pete

[oded kishony]

By the way
Eistein only owned small sailboats (as far as I know)

Incidentally, I played in a quartet, whenI lived on Long Island, whose members had played with Einstein. I also recently saw a violin that Einstein had taken apart and was messing around with, trying to improve the sound.

~OK

[Frank]

He had one about 26ft (long/narrow/low) that he lost when Hitler started the 'Jewish thing' in germany

[CharlieJ]

Hey now- let's not leave Mr Rhodes out of that toast. We feel that our Meridian is every bit the equal of any of the Alberg designs.

In our marina we have an Alberg 30, a Triton, a Cape Dory 25 and  Cape Dory 27. Many there feel our boat is the prettiest.  Can't deny ours is the best kept.  Of course, I wouldn't complain about the 30 if it was given to me. ;D

[Frank]

AH.....mr Rhodes was indeed a fine designer !!! Beautiful boats...well worth a toast. But the the cheers Faith put forth was for us 'Alberg ' sailors...Faith-Ariel  ..Joe-Triton  Frank ex Ariel/now Electra (all Alberg) sailors. Kurt and others fit here also. SOOOooooo To Mr Alberg AND now Mr Rhodes......Cheers !!!!!

[CharlieJ]

You know, I have a theory about those old time type designers- Alberg, Rhodes, Stephens, etc. I think they all grew up in an era of wooden boats. So when it came time for THEM to be designers, they drew lines that could be planked, even if they were being built in glass. That's the lines they knew as younger sailors. The lines that you can hang a plank on also give that very pleasing look that most of us prefer in a boat.  Longer overhangs, sweeping sheers, etc.

The  more modern designers never drew a wooden hull and probably never sailed on one- all their experience IS in glass, so they don't have that subconscious feel or restraint that the older guys did.

What do you  think?

[s/v Faith]

The more modern designers never drew a wooden hull and probably never sailed on one- all their experience IS in glass, so they don't have that subconscious feel or restraint that the older guys did.

What do you think?

Yes, I think that is valid.

  Here's to Mr. Rhodes !

  Grog all around....  ;D

[psyche]

Look  at the 8.7 Columbia. they are very stable, have an abundance of room and they are a gream to sail. The keel is a fin but it looks like a modified fuul keel. I have one if you have any questions. Dan

[Joe Pyrat]

Most definitely, the Triton is a wooden boat rendered in fiberglass and has a lot in common with the Folkboat.