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Discussion Starter #1 (Edited)
In the video below about the Cape Dory 33, Jeff Halpern (who is or was a moderator on this forum) said a few things about the CD 33 that unfortunately he wasn't asked to expound upon. I would ask in the comment section on the page of the video but it was uploaded 5 years ago. If Jim is around and would care to comment then great. If anyone else cares to answer then that would be wonderful too.

Jim Halpern's part starts at 2:30.

1) He said he is "not a fan of Carl Alberg."
QUESTION: Why?

2) The Cape Dory 33 would be a "good boat for an experienced sailor if you didn't care about performance."
QUESTION: If you don't care about performance then why would that boat be good for an experienced sailor and not an inexperienced sailor as well?

3) He said "for a new sailor there will be a steeper learning curve to learn how to sail it well."
QUESTIONS: Isn't there a steeper learning curve for a "new sailor" on any boat? And by "new" does he mean a beginner sailor or "new" to sailing the CD33?

4) He said the Cape Dory 33 (or maybe Cape Dory's in general??) "costs more" and "there are better boats for less cost."
QUESTION: What are the "better boats" that cost less than a CD 33?

By the way, I'm looking for a proper blue water cruiser for long distance cruising and I plan on mostly singlehanding.

Thanks!:)

VIDEO: I'm new so they won't let me include the Youtube link until I have 5 more posts. If you go to Youtube and type "Episode #30 Cape Dory Sailboat" into the search box and then go to 2:30 you will see the part I'm talking about.

P.S. How come there's no Cape Dory category on this forum?
 

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Re: Questions about Cape Dory 33 and statements Jim Halpern made about them...

I lived close to where they made CDs. I’ve owned several of them through the years but not a 33. As a general rule.
They are extremely strong boats. Heavy lay up with good quality control and workmanship.
I’ve owned cutters. Both CDs, tayana and PSC. Believe it’s more difficult to sail any cutter c/w any sloop. You have two slots so it’s easy to stall one. It’s also easy to create turbulence and destroy laminar flow. Trick is to trim front to back when going upwind. Also find dropping the stay sail going downwind helps or in stronger winds dropping the main and poling out the foresail with staysail on the other side. This is a generic problem with any cutter as is tuning the rig correctly.
They have a lot of wetted surface being a full keel boat. With its soft bilges and heavy construction it adds strength and longitudinal stiffness but makes for a slow boat. Again this is generic to any full keel boat of that period.
They back up poorly. Again generic to hull shape and resultant attached rudder.
They point poorly. Ditto.
I singled smaller CDs for several years. They stood up to squalls and several gales without complaint. A surprisingly good heavy weather boat. They were heavy enough for lwl that they had a predictable, fairly gentle motion in a seaway which was reassuring.
The bow stayed ahead of the stern when surfing so only minor input required to prevent broaching.
I like Carl Alberg designs. Put him up with Lyle Hess,and Creelock as NAs of that period who designed good seaboats. Think hitting on Alberg for issues that are generic is unfair. Think I would go to sea in an Alberg design as readily as other NAs designs.
In that size range would prefer the PSC34 ( owned one and its a great boat) but that’s personal preference. The PSC is already set up to single and is a better performer.
 

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Re: Questions about Cape Dory 33 and statements Jim Halpern made about them...

Btw if you have the bucks the Rustler 36 is a rtw boat in that size range. Truly a great design for ocean sailing in that size range. Keel wet-stick dry.
 

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Re: Questions about Cape Dory 33 and statements Jim Halpern made about them...

Packing to return to my boat but got a chance to look at the video. He presents his opinion. Given its not an Alberg design those comments are irrelevant. The lady’s displeasure about space is true for many of the boats of that period. They are relatively narrow for loa. This often advantages comfort particularly going to weather and at anchor in a swell but that’s boat specific. Not having cruised this design don’t know if it’s true here. The business about “experienced sailor” is hogwash in my opinion. Been doing this for awhile and for each new boat (up to 7 or 8 at this point) I’ve been a complete newbie when I first got them. The vid doesn’t show what’s important to you beyond engine access. The rig. Both standing and running. The cockpit. The deck. The ground tackle gear. The steering linkage and so on.
Would not base your decision on this video. It’s distinctly unhelpful. You don’t buy a brand or even a model of that brand. You buy a boat. Look at that boat and judge. Even now I wouldn’t buy a boat without canvassing the opinions of more experienced friends (go shopping with one), review of the owners group on the Internet (find out the weaknesses and common troubles) and the opinion of a good surveyor. Once you have a short list get your significant other or wife to decide.
 

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Re: Questions about Cape Dory 33 and statements Jim Halpern made about them...

First of all, just for the record, my name is Jeff Halpern, or Jeff_H around here (not Jim) ;) but the good news is that I answer to anything that I have been called more than once. I assume that the video in question is "Sailing Nervous", where I have been a technical advisor to Vince since he started that series. It is important to understand that the 5 to 7 minutes that show up in the various videos was edited out of many hours of conversation, both taped and just in casual conversation, as well as dozens of emails explaining the reasons behind those comments. But also these vignettes do not provide background into the audience for those comments which were specifically directed at Vince and Amy's needs and capabilities, rather than those of the general public. As edited they are not inaccurate, but as edited they are an incomplete thought which therefore can be misinterpreted or misleading.

To answer the OP's questions:
1) He said he is "not a fan of Carl Alberg."
QUESTION: Why?

I completely stand behind my comments that I don't think much of the quality of Carl Alberg's designs both as compared to designs by other designers of the same period, or as viewed with the benefit of hindsight which in large part derives from the vast amount of scientific research and knowledge that has been gained in the nearly 40 years after his active years of practice. Carl Alberg was still practicing during the period when I was studying yacht design, and I studied his work in the same way that I studied most of the popular designers of that era. Having sailed on a broad range of Alberg designs, and designs by his contemporaries, I consider him one of the lesser talented designers of that era.

While I agree with some of Outbound's comments, I think that it is a mistake to say "Put him up with Lyle Hess,and Crealock as NAs of that period who designed good seaboats." Viewed from the type of designs that they produced, I would group a designer like Lyle Hess in with other similar period and design type designers such as the William and John Atkins, John Alden (pre-Alberg), Wilbur Morse, John Hanna, Samuel Crocker, some of Starling Burgess's cruising designs, William Garden, William Hand, George Stadel, Colin Archer. These were designers whose designs were in large part derived from Atlantic Coast working watercraft. From my perspective, working watercraft were highly evolved to be seaworthy, easily handled by a small crew, to sail well in a broad range of conditions when heavily loaded, and have good motion comfort. Working watercraft had to have those characteristics because they were out there in all kinds of conditions and failing to meet those criteria endangered the crew and their livelihood. Over time as new ideas were tried, they either were seen as an improvement and so became and integral part of the type form or were abandoned as detrimental. The mix of carrying capacity, seaworthiness, ease of handling made and still make these type forms a reasonable choice for small cruising boats, as long as performance is not a criteria.

I would not lump Crealock in with either the designers of working water craft derived designers or with the likes of Carl Alberg. Crealock, like Bob Perry's early work, fall in another category, what I would term 'composite' (my term), meaning taking the best lessons from both modern yacht design and traditional working water craft designs and combining their vest virtuous features to produce a boat that is better cruising boats than either, but not representative of either approach. While some of Bob Perry's earliest designs would fall in the slightly updated working watercraft based design, I personally think that Bob Perry's composite designs generally produced more well rounded boats as compared to Crealock's work.

When you talk about working watercraft there are a number of consistent characteristics that can typically be found in those designs no matter where they were developed around the north Atlantic. These includes very long water line lengths relative to length on deck, moderate beam, moderate form stability (albeit less than is popular today), comparatively fine entries (at the waterline), good pitch damping, and full length keels or keel centerboard combinations. While science has shown that the full length keel has no impact on seaworthiness or seakindliness. and in large part reflects the materials and methods of the day, scientific research has found that these other characteristics have been demonstrated to be consistent with producing a seakindly and seaworthy boat. (A quick clarification on the fine bow comment. When you look at traditional watercraft in the water, many working water craft design types appear to have very full bows and sterns, but when you look at the lines drawings, most had comparatively fine entries and runs at the waterline and below the waterline.)

In contrast, Carl Alberg's work was largely completely at odds with traditional yacht design principles and with the scientific principles that produce a seakindly and seaworthy boat. By and large the majority of Alberg's designs have been badly corrupted by the racing rules of the early to mid 20th century rather than conforming with the principles considered to ideal for a cruising boat.

To understand Carl Alberg's work, it is helpful to understand where Carl Alberg started. As a young man he designed a series of very successful Skerries and Square Meter class boats. The skerry and square meter rules promoted designs with extremely short waterline lengths. (Typically 50-60%of the length on decks) that were extremely narrow, and with fin keels (as defined in that era) with attached rudders. These boats were intended as inshore and flat water race boats and not for offshore use. Compared to cruising boats, offshore race boats, and working watercraft of that same era, these were tricky boats to sail, slow, not very seaworthy and with miserable motions.

Alberg's designs for those classes were marked by very full bows, extremely pinched sterns, extremely narrow beams, fin keels (i.e. keels with their fore foot sharply cut away and trailing edge so far forward that the bottom of the keel is less than 50% of the length of the boat) with attached rudders. These characteristics, were known then, and we now know are the opposite of the ideal hull form for a cruising boat. Alberg came to the US when he was recruited by John Alden to help compete with the progressive designers of the day such as Olin Stephens, Starling Burgess, Clinton Crane, and so on. Those designers were adapting inshore racing boat principals to offshore race boats. (This was a topic of discussion when I worked for Charlie Wittholz who worked for John Alden during the period that Alberg was at Alden's office.)

Up until the time that Alberg was recruited by Alden, Alden's designs were based on traditional working watercraft. They were good seaworthy designs and quite fast on a reach but were clobbered under the rating rules of the day. Alberg's designs done in the Alden office are easily distinguished by the shift to less wholesome designs, marked by proportionately shorter waterlines, and narrower beam, fuller bows, more extremely cut away keels, and less powerful hull sections.



2) The Cape Dory 33 would be a "good boat for an experienced sailor if you didn't care about performance."
QUESTION: If you don't care about performance then why would that boat be good for an experienced sailor and not an inexperienced sailor as well?

This is a little of an out of context quote. I often say that there are no 100% universally right or wrong answers in sailing. Most need to be qualified. There are few less 100% universally right or wrong answers than what is the right boat for any particularly sailor. All of us choose boats based on some mix of our aesthetic tastes, personal preferences, goals, capabilities, experience, model availability, and budget and so on. An experienced sailor might have some mix of the above that would incline them to consider the Cape Dory 33 to be the right boat for them since they would in theory know full well what they were getting into and will willing to look past the liabilities of a design like this for their perceived virtues. A new sailor generally lacks the experience to understand the severe liabilities of a boat like this.

3) He said "for a new sailor there will be a steeper learning curve to learn how to sail it well."
QUESTIONS: Isn't there a steeper learning curve for a "new sailor" on any boat? And by "new" does he mean a beginner sailor or "new" to sailing the CD33?

An ideal platform to learn to sail well in a short period of time is a boat that is responsive enough to provide input to the helmsmen and sail trimmers that they can learn quickly what works and what does not work. The Cape Dory 33 is not responsive enough to be a good candidate. If you are Vince and Amy, (for whom that comment was directed) who knew next to nothing about sailing or boats, and wanted to learn to sail well quickly and go voyaging, the Cape Dory 33 would have been near the bottom of my list as a recommendation.

Plus being aimed at Vince in particular, Vince had a real aversion to heeling and the Cape Dory 33 is very tender and would scare the bejesus out of Vince in even moderately gusty conditions. A more experienced sailor would both roll with the punches and know what to do to keep the boat moving comfortably.

But beyond the specifics of Vince and Amy, I still think these are really crummy boats for a beginner for a variety of reason. Their limited sailing abilities will reduce the number of days that the boat can be sailed. Sailing boats like these takes more judgement than something that is more forgiving. If somehow the beginner does somehow learn to be a good sailor, they will quickly outgrow the boat's limited capabilities. And for some, the boat's lack of performance will reduce the cruising options and simple joy of sailing to the point that they lose interest in the sport. (I have seen this happen quite a few times)

4) He said the Cape Dory 33 (or maybe Cape Dory's in general??) "costs more" and "there are better boats for less cost."
QUESTION: What are the "better boats" that cost less than a CD 33?

Again this was aimed at Vince and Amy, but generally applies. The interior of the Cape Dory 33 is cramped as compared to other boats that are out there and Vince and Amy planned to live aboard and ultimately cruise to the Caribbean. CD 33's are short on carrying capacity, water capacity and the ability to add water capacity. The Cape Dories that they were seeing were extremely expensive boats for their age and condition. I had given him a long list of boats that were on the market at the time that were $10-30,000 less than the Cape Dories that he was considering. Some were slightly bigger boats and some where clearly more or less suitable. Off the top of my head, some of the list of boats considered included a Pearson 367 Cutter, Niagara 36, Bristol 33/34, Mariner 36 (US rather than Asian), Vinyard Vixen, CSY33, A particular Cheoy Lee 36, Dufour 4800, Ericson 36C, Wauguiez Gladiator, Tartan 34 (for its shoal draft), Aloha 34, Bristol 35.5 and others.

I apologize that some of this was cut and paste from my comments on an earlier discussion of Carl Alberg.

Respectfully,
Jeff
 

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Re: Questions about Cape Dory 33 and statements Jim Halpern made about them...

Wow, fantastic stuff, very valuable, thanks
 

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Re: Questions about Cape Dory 33 and statements Jim Halpern made about them...

Our second of 5 was a CD28. Some old first hand observations from an old guy on what is not exactly the same boat....

Sailing: It is full keel. That means slower, but we won a race, just one, how did that happen? It was blowing as stink. Similar sized boats were overpowered. The wind shifted and the race committee didn't reset the course....it ended up being two long reaches. This should tell you what you need to know. Handles a blow beyond it's size class, loves to reach (what boat doesn't). Also, with a full keel you can walk away from the wheel for a bit, and it will track without an autopilot. It points poorly, tracks well.

Living: These boats are all narrow. The living space is small for their size. We were young, it didn't matter. As I get older comfort matters more. YMMV.

Anchoring: Bow sprits are nice.

Docking: Never met a full keel boat that handled well under power in reverse. Embrace the prop walk.

Maintaining: Hope you like teak. If you do, then maintenance is worth the trouble. Again, YMMV.

Going Aground wrapping stuff on prop etc: Tends not to break things with that full keel, rudder fully supported as well, prop in an aperture which causes less but does not fully prevent a lobstah pot from getting in there, ups your odds though.

Looks: If you like traditional boats, you like it...if not you don't.

Age: We had some trouble with leaks along the deck/hull joint. Check for this.

As far as skill level for new sailor, all that stuff. This may be the only place where I respectfully disagree with Jeff, who BTW has way more credentials to comment that I. Look, it's just a sailboat with a few strings on it. Point it where you wanna go, if the sails are flogging, point a little less close to where you want to go, and when it's pointed there adjust the strings just tight enough so the sails are not flogging, but would be if you loosened them just a little. Chances are the boat will move. At least the 5 we owned worked this way.

Let's face it, boat ownership and boat selection is not rational. That said, unless I loved it, had to have it, 5 boats later I'd probably select something else. One broker once said to me when talking about old B40's, that it's like buying an MG with wire wheels. Sometimes, you just gotta have it.

Another friend described this as a zeroth world problem (one up from first world). We are discussing the best choice of something none of us need, but most of us here have chosen to acquire, that's only purpose is to bring you joy. Only you can pick the boat that does that.

Good luck!
 

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Re: Questions about Cape Dory 33 and statements Jim Halpern made about them...

Had a Mariner 36. Did a Marion Bermuda in her. Agree she’s a good design. Appreciate your thoughtful comments.
 

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Discussion Starter #10
Re: Questions about Cape Dory 33 and statements Jim Halpern made about them...

Btw if you have the bucks the Rustler 36 is a rtw boat in that size range. Truly a great design for ocean sailing in that size range. Keel wet-stick dry.
The Rustler 36 is out of my price range but she sure is a beauty!
 

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Discussion Starter #11
Re: Questions about Cape Dory 33 and statements Jim Halpern made about them...

Packing to return to my boat but got a chance to look at the video. He presents his opinion. Given its not an Alberg design those comments are irrelevant. The lady’s displeasure about space is true for many of the boats of that period. They are relatively narrow for loa. This often advantages comfort particularly going to weather and at anchor in a swell but that’s boat specific. Not having cruised this design don’t know if it’s true here. The business about “experienced sailor” is hogwash in my opinion. Been doing this for awhile and for each new boat (up to 7 or 8 at this point) I’ve been a complete newbie when I first got them. The vid doesn’t show what’s important to you beyond engine access. The rig. Both standing and running. The cockpit. The deck. The ground tackle gear. The steering linkage and so on.
Would not base your decision on this video. It’s distinctly unhelpful. You don’t buy a brand or even a model of that brand. You buy a boat. Look at that boat and judge. Even now I wouldn’t buy a boat without canvassing the opinions of more experienced friends (go shopping with one), review of the owners group on the Internet (find out the weaknesses and common troubles) and the opinion of a good surveyor. Once you have a short list get your significant other or wife to decide.
Good advice. Thank you. I still can't post links, but according to SailboatData.com and Wikipedia, Carl Alberg was the designer of the CD 33.
 

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Discussion Starter #12
Re: Questions about Cape Dory 33 and statements Jim Halpern made about them...

While science has shown that the full length keel has no impact on seaworthiness or seakindliness.

I had given him a long list of boats that were on the market at the time that were $10-30,000 less than the Cape Dories that he was considering. Some were slightly bigger boats and some where clearly more or less suitable. Off the top of my head, some of the list of boats considered included a Pearson 367 Cutter, Niagara 36, Bristol 33/34, Mariner 36 (US rather than Asian), Vinyard Vixen, CSY33, A particular Cheoy Lee 36, Dufour 4800, Ericson 36C, Wauguiez Gladiator, Tartan 34 (for its shoal draft), Aloha 34, Bristol 35.5 and others.

Respectfully,
Jeff
Jeff, sorry I called you "Jim." It would be very interesting to see everything that was edited out of that video.

Well, there was some real gold in that post of yours. Thank you. I never realized this until you brought it up, but I can definitely see how those early boats with their narrow beams, long overhangs, short waterlines were influenced by the early square meters.

Regarding... "While science has shown that the full length keel has no impact on seaworthiness or seakindliness." That surprises me, and especially the seakindliness part. Care to expound on that when you get a chance, please?

I will check out the boats you mentioned. So far I sure like the looks of the Pearson 367. Any thoughts on the Vancouvers?
 

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I've owned a 1965 Alberg 35 for five years, I sail it out of Baltimore, some single handing, mostly cruising. I've never raced her. I think the best comment made in all of the thread here is, "You don't buy a model, you buy a boat." Mine was refitted by two previous owners. One was a cabinet maker who built beautiful wooden cabinets port and starboard and a sold, gorgeous chart table on the port side. The other rewired the boat and made many good choices about upgrades as well as doing meticulous maintenance.

The boat, like many of Alberg's design is not a full keel, it's a cutaway keel, in the case of my boat, with encapsulated ballast and a prop in an aperture, attached rudder. That said, it has the characteristics mentioned above: it took me several years to learn to back the boat more or less reliably. As someone said, "embrace the prop walk". On the other hand, once you DO embrace the propwalk, you can turn the boat quite sharply. I have spun mine in its own length when I went down the wrong fairway in the marina. But backing any distance is a long, slow process; I generally just try not to do it and I've learned to use spring lines to get out of my slip.

The boat is fun to sail. For me, that's the point. I have a 135% genoa on a furler and a big, full battened main. In a decent breeze upwind, she typically heels 20 degrees and then sticks with the cap rail just out of the water. I like that; I'm close the water and the feeling of slipping through it.

The boat is solid. There are all kinds of stories of A35's making significant voyages. I have no doubt the boat is fair more capable than I am and that's a good feeling. She doesn't have the space of a modern boat. I've had no problem living on the boat for a month or so at a time in the summer. When my wife is with me, there's plenty of space for the two of us.

She makes me feel good; isn't that the point? My wife said once that this was the sort of boat I drooled over when I was 14 and that's probably true. I know that I've never walked away from her without looking back and smiling. That's also the point for me.
 

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Re: Questions about Cape Dory 33 and statements Jim Halpern made about them...

Jeff, sorry I called you "Jim." It would be very interesting to see everything that was edited out of that video.
There is no need to apologize. I thought it was funny. it reminded me of the PT Barnum quip, "I don't care what the newspapers say about me as long as they spell my name right.” But for me, that expression would be "I don't care that you know who I am as long as you think about the ideas that are being presented."

And if it makes you feel any better, I made several mistakes in that clip. First of all, the Cape Dories that Carl Alberg did not design were the Cape Dory 270 which was designed by Dieter Empacher, and the Cape Dory 30 MkII which was designed by Clive Dent. Both of those boats were designed in the 1980's rather than the 1970's. I am not sure whether I slipped up when I said that the boat in question was not designed by Alberg or the editing led to the appearance of a mistatement. Vince had also talked about the smaller Cape Dory 30 mkII so I may have been referring to that rather than the 33 shown else where in that video when I said the boat in question was not designed by Alberg, but there is also a very good chance that I simply got it wrong.

Well, there was some real gold in that post of yours. Thank you. I never realized this until you brought it up, but I can definitely see how those early boats with their narrow beams, long overhangs, short waterlines were influenced by the early square meters.
Its important to understand that pretty much all of Carl Alberg's designs appears to be heavily influenced by his early work with Square Meter boats. Except perhaps for the Triton (and to a lesser extent the Sea Sprite), pretty much all of his designs had excessively full bows that hurt their motion comfort and performance in a chop. All had excessively short waterline lengths that unnecessarily compromise tracking, seaworthiness, motion comfort, carrying capacity, ease of handling, interior volume, and performance. Almost of all his designs had heavily cut away fore foots, and keel hung rudders that were pulled very far forward in the boat; all of which negatively compromised tracking, ease of handling, and maneuverability, while greatly increasing helm loads and the need for more frequent helm inputs.

Regarding... "While science has shown that the full length keel has no impact on seaworthiness or seakindliness." That surprises me, and especially the seakindliness part. Care to expound on that when you get a chance, please?
So this is complicated to explain.

To begin with, it is important to understand that the sea has not changed, but our understanding of it has. In that regard, it is particularly true that our understanding of what makes a seaworthy and seakindly boat has greatly changed over the past 4 decades. It is amazing how much research has happened during that period and how the mix of modern high-speed videography, miniaturized sensors, and computer technologies, when combined with traditional tank testing and instrumenting full sized vessels has greatly and rapidly increased the design communities knowledge base.

Boiled down to the simplest the key design factors that control seakindliness roughly in order of importance are waterline length, weight and buoyancy distribution, damping, and buoyancy rate of change with heel and pitch. Out of those factors derive the components that are most often visualized as being the way to analyze motion comfort such as the weight and buoyancy distribution producing initial and ultimate stability, or roll and pitch moments of inertia impacting the deceleration at the end of a roll. Or, for example, damping and buoyancy rate of change with heel and pitch controlling the angles of rotation and acceleration and deceleration during heel and pitch.

Based on the current science, old formulas such as the Motion Comfort Ratio and the Capsize Screening provide absolutely no useful information regarding either motion comfort or the likelihood of a capsize since neither formula contains the most of the most critical factors controlling both.

Across the board, assuming all other factors are reasonably moderate, the single greatest determinant of both motion comfort and seaworthiness is water line length. In testing and examination of disasters at sea, and actual vessels, Over and over again, water line length is the one design variable that more than any other has been consistently shown to improve motion comfort and seaworthiness. In other words, if you have two boats of reasonably similar displacements, the boat with the longer waterline length will be the more more comfortable and seaworthy. So if we compare two boats with similar displacements, i.e. the Cape Dory 33 to a boat like the Caliber 33, the Caliber, with its 20% longer water line, would be expected to have a much more comfortable motion and be more seaworthy.

Of course there are other factors that enter into this. So for example, in terms of weight distribution, the Caliber also has a larger ballast to displacement ratio than the Cape Dory and of course that would also help with motion comfort and seaworthiness.

Addressing the question more specifically, keels come into play in both motion comfort and seaworthiness in a variety of ways. But more than anything else, their biggest role is in the amount of damping produced. Damping should be thought of as the resistance to motion and more typically to rotational motion. To explain damping, if you visualize forcing a keel to rotate sidewards through the water, or a sail through the air, as the boat rolls, the sail and keel creates a resistance to the boat rolling. That resistance slows the roll rate and reduces the kinetic energy stored by the boat so that the boat rolls through a smaller angle.

In the case of the amount of damping force created by a keel, the damping force is a product of the area of the keel and the distance (lever arm) that centroid of the distribution of the area of the keel is from the axis of rotation. In the case of a longer (fore and aft) keel boat, the area of the keel can be very large as compared to a fin keel. But because longer keels generally occur on boats with some mix of deeper canoe bodies, and slack bilges, the axis of rotation is very low in the water. And also longer keels tend have a shallower draft raising the centroid. That combination means that the lever arm dimension between the centroid of the keel area and the axis of rotation is very short. Therefore since the lever arm is squared while the area of the keel is linear, long keels tend to produce substantially smaller damping moments. In other words the boat with longer keels would tend to rotate faster, through a wider angle than a similar boat with better damping. And this smaller amount of damping means that the rotation can more easily get out of sync with the wave train resulting in a harder stop at the ends of the rotation as the topsides enter the water. The effect of this is further amplified when suddenly the form stability of the topsides hitting the water rapidly increases the resistance to heel.

But that is simply a single example. There is a lot to seakindliness and that is only a single example. If you think about the 6 types of motion, the only form of motion that a long keel potentially impacts positively is yaw. But because of the larger keel area, its a toss up on whether a long keel really does reduce yaw. While the longer keel would tend to have a larger resistance to rotation, it also has a larger are for the waves to act on thereby imparting more force on the boat. So depending on the specifics of the boat and the wave, the impact of the yaw on a longer keel can just as easily translate into greater yaw and roll angles and acceleration.

Maybe I can put the long keel thing into a different perspective this way. In the Golden Globe Race, virtually all of the boats had long keels, and virtually every one of them that made it to the southern ocean was rolled 180 degrees or more at least once. Although much lighter and with tiny fin keels, none of the Class 40's have been rolled. While its true that no one in their right mind would want to cruise a Class 40, none the less it does give a sense that a long keel is not necessarily more seaworthy.


Any thoughts on the Vancouvers?
Bob Harris was a very talented designer. I liked many of his designs. I am not a fan of his Vancouvers for a variety of reasons mostly related to the hull forms in the areas near the stern. I may be remembering this incorrectly but I seem to recall that these boats used scrap iron in concrete ballast and if true would be a deal breaker for me. Maybe someone else can confirm that one way or another.

Jeff
 

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As the happy owner of an Alberg 30 which I have lived on and sailed almost daily for the past five years, it always distresses me to hear others proclaim his designs should not be considered. “Oh” they say “his designs have so many faults. His hulls are too narrow, his keels are too long, his waterlines are too short, his rudders are too slanted.”
Well, if all of these are truly design faults then Carl Alberg was all the more genius because he managed to blend all these faults into boats of ageless beauty that are a joy to own and a pleasure to sail, that are as fun to sail and as easy to single-hand as a dinghy yet are as sound and seaworthy as any vessel their size, that have sold by the hundreds to probably thousands of owners, and many of which are continuing to sail gracefully into their 5th decade.
Other than many years of experience sailing on many different boats I haven’t any particular credentials for armchair criticism of any particular boat designer. So in my defense and praise of Carl Alberg designs I will just say that for me the enjoyment and thrill of sailing is not just about bottom line fastest time around a course or to a destination, and I would rather the feeling that I am living on a boat than feeling that I am sailing in a condominium.
 
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