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Old 10-08-2011, 19:16   #16
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Re: Weight Questions

Just a small point from the peanut gallery; one of my design mentors - probably others, as well - has zero faith in published displacements. in working on a design for a 37 footer, my displacement has been revised a few times & the design is far from finished. How a boat hull/deck is built will, of course, vary the designed displacement, as will types/sizes of equipment. Add to this after-build additions & loads of stores, crew, etc., & that 10,000lbs. boat one is gazing at may be 13,000lbs. Sites like CF are invaluable when considering which production boat one will buy because there are usually a few who have owned one, a few who have delivered/crewed on one, even the odd designer, etc. . Probably my only regret in my up-coming voyage is the time I won't be able to flip on my computer & read the great info. that so many here provide. But, I can suck it up & live with that regret.
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Old 10-08-2011, 20:09   #17
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Re: Weight Questions

There are just so many variables to consider that it makes it difficult to make accurate statements that cover most situations. This is rapidly dissolving into a full keel/fin keel or heavy/light displacement debate.

What is true is that a heavier boat will have greater momentum - so it takes longer to accelerate, but carries her weigh longer. So a heavier boat is less likely to be slowed by waves as much as a lighter boat when punching into them. A heavier boat will also be less affected by the cruising gear and stores that are loaded onboard because they will make up a smaller percentage of the boats total mass.

Other than that, most bets are off. A heavier boat MAY have greater righting moment, but may not. It may be less likely to move around or have a slower motion in a seaway. A heavier boat may be slower downwind or in light airs .... but it may not. So much depends on the sail area carried, the righting moments, the weight distribution, the hull shape, wetted surface, effective waterline length, yadda, yadda, yadda.
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Old 11-08-2011, 10:14   #18
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Re: Weight Questions

Well..... I guess I assumed the CF people were not talking about racing dingys or open 60's! Yes published displacements are bunk for sure.
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Old 11-08-2011, 13:23   #19
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Re: Weight Questions

So let's see if I've got this right, a heavy boat sailing in choppy seas is slower than a light boat powering in the same conditions ONLY because of boat displacement.

PHRF takes into account boat performance. Performance is affected by a bunch of things from wetted surface, hull shape, rig, sail area, mast height, etc. etc. ULDB flyers like the Hobie 33 and Olson 30 do very well off the wind because they surf easily. Light displacement accelerates quickly enabling them to catch waves easier. They are not flyers upwind, however, and I wouldn't want to do more than daysail in any of them. Most IOR boats that tend to be heavy in comparison to current racers will beat most of the new boats in beating conditions to a close reach. For reasons not necessarily related to weight, the IOR boats aren't so hot off the wind.

A full keel boat will not respond quickly to helm input, this makes them slower to come about and must sail a longer distance to effect a given degree of course change. This makes them more vulnerable to falling into irons should they lose forward momentum. I don't have the fingers and toes to count the number of times I've had to gybe rather than tack my heavy displacement boats in short choppy seas. In smooth water with enough way on, they'll come through the wind almost every time making a long smooth curve through the water. In contrast, I see fin keel boats flop over on the other tack in what seems like less than their boat length. My current not so heavy boat full keel boat had to back and fill using prop torque to turn into the slip. Saw numerous fin keel boats do 360's in the same situation where I could barely turn a 90. Haven't tried to tack a light weight fin keeler in the Potato Patch off SF in light air but feel they would do better than a long keel simply because they turn so much faster.

Heavy boats can be just as fast as lighter boats given enough sail area, down to a point. You just aren't going to drag the long keel of a boat like a W32 through the water in very light air like you can a rapier thin, bulb keeled, fllat bottomed boat. There is just too much skin friction from all that wetted surface. In their defense, these are conditions most people would have long since turned on the engine unless in a race. Given a little bit more wind and sail area/displacement ratio commensurate to a light weight flyer and a heavy boat can often eat up a lighter boat except in surfing conditions.

What it boils down to is what kind of boat do I want to be in making long passages. For me, the answer is weight. These boats have easier motions and all the speed I need for the day in, day out conditions I've found at sea. I usually get places faster than other boats and in a lot better physical condition. Better yet, don't have to worry about the care and feeding of more than an absolute minimal crew to keep the boat sailing to it's optimum. Others will go for a light weight flyer and most will be somewhere in between.
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Old 11-08-2011, 20:09   #20
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Re: Weight Questions

All good info. I was simply trying to respond within the context of the op s post without wrting a book. I see weve gone far afield from that to open 60s and planing boats.
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Old 11-08-2011, 20:29   #21
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Re: Weight Questions

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Originally Posted by roverhi View Post
What it boils down to is what kind of boat do I want to be in making long passages. For me, the answer is weight.
For me the answer is size. Bigger boats tend to have greater weight, generally, and greater waterline as well.
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Old 12-08-2011, 04:47   #22
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Re: Weight Questions

Bigger doesn't always mean longer; but generally bigger is better. Keep in mind that recorded weight and length are rarely the same as actual and that a long waterline with heavy displacement make a true blue water boat.
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Old 12-08-2011, 08:43   #23
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Re: Weight Questions

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Bigger doesn't always mean longer; but generally bigger is better. Keep in mind that recorded weight and length are rarely the same as actual and that a long waterline with heavy displacement make a true blue water boat.
Not so.. the heavy weight boats of yester-year were built like that because that was the knowledge known at the time, and this has been descussed in depth on this form..
as times change, so do designs and materials..
If you want to bob around the ocean in a heavy weight tank, thats a choice you make on your own, but newer designs and materials have shown that the Blue Water boat of today, is a sleak, well designed, performance hull, with the ability to cross oceans in a "Fast Passage" giving the cruiser a comfortable ride.........
The full keel, wineglass style, heavy weight cruiser is in comparison to a 1948 ford 1 ton truck.. it did its job well, for its time..but times have changed, and the "True Bluewater Boat" of today, is not a heavyweight..
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Old 12-08-2011, 12:39   #24
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Re: Weight Questions

Spoken like a true Bennie owner who's swallowed the advertising and too much salt water. Why is that when it comes to Jenneau or Beneteaus they always a good racer when racing's the topic, a good coastal boat when asked and the better cruiser when by comparison all of course being 42's? One can sail a pallet of Budweiser and head out to sea; but calling it the best (unless you're looking for a party) plainly lacks experience and foresight. Heavy cruisers are not racing hulls, however they do perform; with a gentle ride (with all the right math) and a take you anywhere, anytime sense of security from the top of the rigging to the bottom of the keel, regardless of their age or when they were built.
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Old 12-08-2011, 13:34   #25
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Re: Weight Questions

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Spoken like a true Bennie owner who's swallowed the advertising and too much salt water. Why is that when it comes to Jenneau or Beneteaus they always a good racer when racing's the topic, a good coastal boat when asked and the better cruiser when by comparison all of course being 42's? One can sail a pallet of Budweiser and head out to sea; but calling it the best (unless you're looking for a party) plainly lacks experience and foresight. Heavy cruisers are not racing hulls, however they do perform; with a gentle ride (with all the right math) and a take you anywhere, anytime sense of security from the top of the rigging to the bottom of the keel, regardless of their age or when they were built.
Now there you go, knocking the brand of boat I own, and in none of my posts, did I mention anything about Beneteau or My FIRST 42 which by the way, is almost 30 years old..
I didnt mention racing hulls, didnt state any brands, or models, ..
we're not comparing brands here but instead weight differences of cruisers.. and at one time, a heavy weight boat was concidered the only true cruiser, not because of its weight but because of the construction of the boat caused it to be heavy.. didnt start out that way, but ended up with all the reinforcement, it was built heavy..
with new construction methods, the structural areas of the hull can be built at a fraction of the weight its older brother had.. thus giving its crew a stable, well built, boat to cruise with..
If you are going to set around wallowing on a pallet of budwiser, the weight will give you a sea kindly ride..
in the newer designed hulls, forward movement, give sea kindly motion and the faster the boat moves, the smother it gets..
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Old 13-08-2011, 06:03   #26
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Now there you go, knocking the brand of boat I own, and in none of my posts, did I mention anything about Beneteau or My FIRST 42 which by the way, is almost 30 years old..
I didnt mention racing hulls, didnt state any brands, or models, ..
we're not comparing brands here but instead weight differences of cruisers.. and at one time, a heavy weight boat was concidered the only true cruiser, not because of its weight but because of the construction of the boat caused it to be heavy.. didnt start out that way, but ended up with all the reinforcement, it was built heavy..
with new construction methods, the structural areas of the hull can be built at a fraction of the weight its older brother had.. thus giving its crew a stable, well built, boat to cruise with..
If you are going to set around wallowing on a pallet of budwiser, the weight will give you a sea kindly ride..
in the newer designed hulls, forward movement, give sea kindly motion and the faster the boat moves, the smother it gets..
I'd argue there's another advantage to the older heavy full keel designs in that they are a little better able to take a hard hit on a floating cargo container or a reef. Search the news and you'll see it happens ,one of those fin keel light boats loses it's keel or they hit a container or a whale and get a big hole.
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Old 13-08-2011, 07:41   #27
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Originally Posted by Seahunter
Spoken like a true Bennie owner who's swallowed the advertising and too much salt water. Why is that when it comes to Jenneau or Beneteaus they always a good racer when racing's the topic, a good coastal boat when asked and the better cruiser when by comparison all of course being 42's? One can sail a pallet of Budweiser and head out to sea; but calling it the best (unless you're looking for a party) plainly lacks experience and foresight. Heavy cruisers are not racing hulls, however they do perform; with a gentle ride (with all the right math) and a take you anywhere, anytime sense of security from the top of the rigging to the bottom of the keel, regardless of their age or when they were built.
Spoken like a true ford pickup driver trying to explain to you that leaf springs have a place in a modern suspension.

Virtually no modern yacht manufacturer of note is making long keeled boats. Moody, HR, naiad, oyster even Taiwan/ chinese stuff like Tayana have moved to fin and either spade or semi balanced rudder.

The simple fact is that a reasonable fin keel and spade rudder boat built to modern understandings of GRP construction will sail the doors off anything else.

Keep using the pickup truck

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Old 13-08-2011, 18:27   #28
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There was good reason that Jessica Watson chose a Sparkman and Stephens full keel proven design. Four knock downs no damage. Let's remember how Abby faired in one knock down. Enough said.
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Old 13-08-2011, 18:49   #29
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Re: Weight Questions

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There was good reason that Jessica Watson chose a Sparkman and Stephens full keel proven design. Four knock downs no damage. Let's remember how Abby faired in one knock down. Enough said.
need to get your info correct.... the Sparkman and Stephens that jessica watson used was a fin keel.............
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Old 13-08-2011, 19:09   #30
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Re: Weight Questions

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I'd argue there's another advantage to the older heavy full keel designs in that they are a little better able to take a hard hit on a floating cargo container or a reef. Search the news and you'll see it happens ,one of those fin keel light boats loses it's keel or they hit a container or a whale and get a big hole.
and in an accident, a 1948 ford 1 ton truck will fair much better than a new Prius...
I'm not knocking the older heayweights, only stating there are newer Mid Weight, NOT ULDBs (ultra lights) that will serve the same purpose and deliver smother ride, and a faster passage......
And we havent even gotton into the rigging on the heavyweights.. the rigging has to be of larger size to support the added wind it takes to propell the heavyweight, larger rigging means more weight aloft, which in turn means more sail area to move it, and on and on.....
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