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Full Keel Vs. Fin or Modified Full Keel

62K views 51 replies 19 participants last post by  vtoz7053 
#1 ·
I've been looking artound the threads and have not seen one that concisely answers my question, so I thought I'd start one.

I'm narrowing my choices down, and it seems that most of my favorites have full keels.

Can someone give me a down and dirty pro-con list for full keel sailboats versus fin keeled ones?

Also, I've seen some keels that appear to be hybrids: ie: very long & shallow fins, or full keels that aren't "really" full length. If need be I'll search out some pics to fill out the discussion.

P.S. : For reference I'm thinking Cabo Rico 38' , Tayana 42' Pacific Seacraft in the same range, maybe a couple of others.

Thanks,
Fred
 
#2 ·
This is a draft of an article that was written for another purpose but covers the material that you seem to be asking about.

"First of all your question seems to be about appendages. In principle Appendages keep a boat from making leeway. They come in many shapes and sizes. Keels are supposed to be a fixed appendage and centerboards generically are moveable appendages that occur on the centerline but centerboards are just one kind of moveable appendage. In more detail:

Keels:
The earliest form of a keel was simply the backbone of the boat extending through the bottom planking. (Like a Viking ship) That works OK with running and reaching sails but when you try to point toward the wind you slip side wards at great speed. As sails and rigs were invented that allowed boats to point toward the wind the keel was extended below the boat either by planking the hull down to a deeper backbone or by adding dead wood (solid timber below the backbone. A planked down keel permitted the space between the planking to be filled with heavy material (originally stone), which served as ballast keeping the boat from heeling. After a while it was discovered that there were advantages to bolting a high-density cast metal ballast to the outside of the deadwood and interior ballast dropped out of fashion.

Full keels:
These earliest keels pretty much ran from the point of entry at the bow, to the aft most point of exit at the stern. Those are full keels in the fullest sense of the word.

They have some advantages; they theoretically form a long straight plane, which keeps a boat on course better (greater directional or longitudinal stability). If you run aground they spread out the load over a larger area reducing the likelihood of damage. Once really planted they keep the boat from tipping over fore and aft. They are easier to haul and work on. You can spread out the ballast over a longer distance and so they can be shallower for the same stability. You have a greater length to bolt on ballast so it is a theoretically sturdier and simpler connection.

They have some disadvantages; a larger portion of the keel operates near the surface and near the intersection of the hull and keel, which are both turbulent zones. They also have comparatively small leading edges, and the leading edge is the primary generator of lift preventing sideslip. Because of that they need a lot more surface area to generate the same lift. Surface area equates to drag so they need more sail area to achieve the same speed. Long keels tend to be less efficient in terms of lift to drag for other reasons as well. As a boat makes leeway water slips off of the high-pressure side of the keel to the low-pressure side of the keel and creates a turbulent swirl know as a tip vortex. This is drawn behind the boat creating drag in a number of ways. The longer the keel, the bigger the vortex, the greater the drag. So they need more sail area again to overcome this drag. To stand up to this greater sail area the boat needs more ballast and a stronger structure, which is why long keelboats are often heavier, as well. (Of course, then the spiral starts again as more sail area is needed to overcome that additional weight as well. It is the classic weight breeding more weight design cycle) Full keels tend to be much less maneuverable.

Fin keels:
By the classic definition of a fin keel any keel whose bottom is less than 50% of the length of the boat is a fin keel. Fin keels came into being in an effort to reduce drag. Cut away the forefoot or rake the stem, as well as, move the rudderpost forward and rake it sharply and pretty soon you have a fin keel. Today, there seems to be a widely accepted belief that a fin keel implies a separated rudder (skeg hung or spade) but in fact early fin keels usually had their rudder attached. No matter what we call them, these comparatively short keels with attached rudders were in all ways were a worst of all worlds situation. They offer all of the disadvantages of both full and fin keels, but with nearly none of the virtues of either. Unknowing or unscrupulous brokers will often refer to boats with fin (or near fin) keels as full keel if they have an attached rudder.

Fin keels with separate rudders seem to be the most commonly produced keel form in the US these days. (I could be wrong, there is a slight resurgence of full keels these days)

Fin keels have some advantages as well. They have less drag as explained above so they typically make less leeway and go faster. You can get the ballast down lower so in theory they are more stable for their weight. They are more maneuverable. They take better advantage of the high efficiency of modern sail plans and materials. They work especially well in terms of roll dampening and so offer advantages in terms of motion comfort.

They have some disadvantages as well, many of these have been offset or worked around by modern technology but at some level they are still accurate critiques. They often have less directional stability than long keel boats so the tend to wander more under sail. Since directional stability is also a product of the dynamic balance between the sail plan and underbody, in practice they may actually hold a course as well as a full keel. In general though you can expect to make more course adjustments with a fin keel. It is sometimes argued that the lower helm loads requires less energy to make these corrections so a fin keel may also require less energy to maintain course. This I think is a product of the individual boat and could lead to a debate harder to prove than the number of angels that can dance on the head of a pin.

Fin keels are harder to engineer to withstand a hard grounding and when aground they are more likely to flop over on their bow or stern. (Although in 40 plus years of sailing, I have never heard of anyone actually experiencing this.) Fins typically have deeper draft. They are easier to pivot around and get off in a simple grounding.

Shoal keel
A shoal keel is just a keel that is not as deep as a deep keel. Today the term seems to be applied mostly to shallow fin keels. Shallow full keels seem to be referred to as shoal draft boats. A shallow fin is a tough animal to classify. Like a fin keel with an attached rudder, I really think it has few of the advantages of either a deep fin or a full keel and has many of the worst traits of both full and fin. This can be partially offset by combining a shallow fin with a centerboard, which is a neat set up for shoal draft cruising.

Bulb Keel:
A lot can be done to improve a shallow fin. One way is to add a bulb. A bulb is a cast metal ballast attachment added to the bottom of the keel. They concentrate the ballast lower providing greater stability and sail carrying ability than a simple shallow keel. Traditionally bulbs were torpedo or teardrop shaped. They have been re-contoured to provide some hydrodynamic properties. Recalling the discussion on tip vortex from above. Shallow keels need to be longer horizontally than a deeper fin in order to get enough area to prevent leeway. This means that a shallow longer fin would generate more tip vortex and more drag than a deeper keel. The bulb creates a surface to turn the water aft and prevent it from slipping over the tip of the keel thereby reducing tip vortex. This does not come free since a bulb increases frontal area and surface area.

Scheel Keel:
Scheel Keels are a specialized form of shoal bulb keel which is shaped to reduce induced drag (tip vortex) and surface area, and lower the center of gravity. Like any shoal bulb keel ity offers a very big improvement over a simple shoal draft fin but do not sail as well as a properly designed deeper fin.

Wing keels
Wing keels are a specialized type of bulb keel. Instead of a torpedo shaped bulb there are small lead wings more or less perpendicular to the keel. These concentrate weight lower like a bulb and properly designed they also can useful in reducing tip vortex. There has been some discussion that wings increase the effective span of the keel when heeled over but this does not seem to be born out in tank testing of the short wings currently being used in production sailboats. Not all wings are created equal. They potentially offer a lot of advantages, but they are heavily dependent on the quality of the design and I really think that many wing designs are not really working to their potential.

Then there is the whole grounding issue. The popular perception isthat wing keels are harder to free is accurate. This seems to be born out by discussions that I have had with towboat skippers on the Chesapeake and with a researcher who worked on a project at the US Naval Academey. According to both wing keels were extremely harder to free. Straight fins were much easier to free, especially when heeled. There also is some evidence that bulbs may be easier to free than fin keels.
Keels that are not really keels:
Swing keels are ballasted centerboards and drop keels are ballasted daggerboards that are ballasted beyond what it takes to submerge themselves. They are really forms of centerboards. More on these in the discussion on centerboards.

Keels that are keels that move.
I said in the introduction that keels do not move. That used to be true. We now have canting keels, which can be pivoted from side to side. They are best designed to be light fins with heavy bulbs that can be canted to windward increasing the effectiveness of the righting aspects of the keel. Just one problem, a keel canted to windward losses efficiency to prevent leeway so they really need other foils to keep leeway in check. I frankly do not like the idea of a canting keel. I think canting keels are too complex and potentially problematic.

Centerboards:
Centerboards are appendages that can be raised and lowered on or near the centerline of the boat. They can rotate up into a trunk or rotate below the boat. Daggerboards are a type of centerboard that raises vertically or near vertically in a trunk. Swing keels are a type of rotating centerboard that actually contains a substantial portion of the boat's ballast. They may be housed in a trunk like a Tartan 27 or 34 or hung below the boat like a Catalina 22. In the case of the Tartan 27 or 34 they are more frequently referred to as a Keel/ Centerboard (abbreviated k/cb). A swing keel is intended to act as a fin keel when lowered and allow some sailing in the partially raised position. My biggest problem with swing keels is that most do not have a positive lock down. In an extreme knockdown they can slam up into the hull greatly reducing the boat's stability. This is a pretty rare occurrence and usually requires big wave action combined with a lot of wind, but I have experienced it out in the Atlantic.

A drop keel is a daggerboard that actually contains a substantial portion of the boat's ballast. These are easier to lock down but can be more easily damaged in a grounding. They generally have better shape than a swing keel and can be more robust, but not always are.

Other appendages: (besides the rudders)
Bilge keels (or twin keels for our English friends) are a pair of keels (usually fins these days) that emerge on either side of the boat and angle out. They offer some advantages. If you let the boat dry out the boat can stand on the two keels and wait the next tide. There are dubious theories about increased efficiency since one is vertical like a good leeway resisting foil and one is canted like a good stability inducing foil. With computer modeling there has been greater success in approaching that theory on large bilge keel boats. While bilge keels do allow shallow draft though, they extremely difficult to free once aground since having the two keels on the ground prevents heeling the boat to get free. In practice bilge keels have enormous wetted surface creating a lot of drag at lower speeds, and produce two very large tip vortexes creating a lot of drag at speed.

Keel Centerboards are a wonderful choice for coastal and offshore cruising. Properly designed they offer nearly the performance of a fin keel, and yet permit access to shallower venues. They can be partially raised to precisely control the center of lateral resistance and therefore offers the ability to have a very neutral helm and great tracking in a wide range of conditions. Properly constructed they have proven to have a long service life. Keel-centerboard boats really proved themselves offshore during the late 1950's and into 1960's.They fell out of popularity with the advent of the wing keel in the early 1980's. The downside is that they are a little harder to maintain, and because the ballast is closer to the center of buoyancy they require more ballast and so end up requiring a higher overall displacement, a higher ballast to displacement ratio, or are more tender, or some combination of the three.

Bilge boards (for the scow guys), are a pair of centerboards that angle out of each side of the boat. They work well on scows but I've never been able to really figure out scows anyway. Seriously, You raise the windward board and lower the Leeward one on each tack and because they are close to vertical they can be small and efficient. I still don't get the scow thing.

Last but not least- Leeboards. Leeboards are foils that are bolted to the side of the hull like on Dutch Jachts and Herreshoff Meadowlarks. Phil Bolger's sharpies use them a lot as well. They have some advantages but they drive me nuts. They are vulnerable in docking and ideally are raised and lowered on each tack also. Some are raised to be hinged feather so they do not need to be raised."

So that's about it. The final is tomorrow- multiple choice and essay.

Jeff
 
#25 ·
what US Naval Academy researcher ?

...
Then there is the whole grounding issue. The popular perception isthat wing keels are harder to free is accurate. This seems to be born out by discussions that I have had with towboat skippers on the Chesapeake and with a researcher who worked on a project at the US Naval Academey. According to both wing keels were extremely harder to free. Straight fins were much easier to free, especially when heeled. There also is some evidence that bulbs may be easier to free than fin keels....Jeff[/FONT]
Last year in a similar thread I challenged the claim that research was done at the Naval Academy on wing keel groundings. To my knowledge that claim has yet to be substantiated by anyone. I went to the effort of inquiring at the Academy to find the principal investigator for their keel grounding study. In fact it was a fin vs. bulb comparison in the study. I communicated with that professor and he was not aware of any such WING KEEL grounding research.

Naturally, I am curious as to the identity of the researcher at the Academy who has done a wing keel grounding study.
 
#3 ·
Thanks Jeff,

That's a very good article explaining what the different types of keels are, and answers some of my theoretical questions.

Issues that I have heard mentioned; and would like some commentary on:

Full Keels and backing down

Full Vs Fins beating to windward

Stability and righting moment

Practical effect on speed (cruising rather than racing)

Blue Water implications

Thanks again,
Fred
 
#4 ·
I think you could draw most of your conclusions from Jeff's very complete answer above:

Full Keels and backing down Fin keels are more manouverable but more difficult to track straight

Full Vs Fins beating to windward Fin keels point higher and give less leeway

Stability and righting moment Fin keels have greater righting moment for the same weight

Practical effect on speed (cruising rather than racing) Full keels are slower

Blue Water implications Such as?
 
#5 ·
I think you could draw most of your conclusions from Jeff's very complete answer above:

Blue Water implications Such as?
Well, I'm not really sure. It seems that a lot of the boats that are generally accepted as "Blue Water Boats" have full or almost full keels. I was wondering if that just happens to be the boats I've been looking at, or if there was some particular advantage. Heaving to, perhaps? Had I read that heaving to is more effective in a full keel boat, and if so, how bad is it in a fin keel?

I don't want to wander too far in this thread into the "What Boat Should I Buy" conversation, because that really belongs in the "Buying A Boat" forum; but I'm trying to get as many variables sorted out before going that route.

I'm curious; Are fin keels better in terms of leeway because of better lift characteristics? ; because it seems somewhat counterintuitive otherwise, thinking that the full keel would put more resistance to being pushed sideways.
 
#6 ·
Heaving to: We must have read the same books, I've always heard that full keels heave to better and create a better "slick" to windward to calm breakinig seas. I don't have any experience heaving to in a full keel but I know that my Islander 26 fin keel hove to rather nicely, only made about 1/2 knot of headway in 30+ knots of wind and while I never hove to in breaking seas it DID appear to make a nice windward slick.

I'm looking for a boat right now and I'm pondering the same things as you. I think I would feel better in a full keel boat making long passages.

Just my two cents.
 
#7 · (Edited)
The greater lift / less leeway of fin keels is due to them having more leading edge.

The leeway advantage of the fin keel is also related to the speed. For instance, even if two boats had the same leeway speed, if the full keel is doing 4 kts with 0.1 kts leeway, then over a 24 kt course it will be 0.6 kts downwind. If a fin keel is doing 6 kts with 0.1 kts leeway over the same course, it will be 0.4 kts downwind.
 
#8 · (Edited)
Fred, re-read Jeff's article. It appears to answer most of your questions, except perhaps the specific characteristics of a full keel, backing down. It doesn't answer all your questions in the specific terms that you're asking them, but it describes the principles that lead you to most of the answers you're seeking.

For example you ask about "Full Vs Fins beating to windward." Jeff says: "[Full keels] have some advantages; they theoretically form a long straight plane, which keeps a boat on course better (greater directional or longitudinal stability)." Later, he explains that : "[Full keels] have some disadvantages; a larger portion of the keel operates near the surface and near the intersection of the hull and keel, which are both turbulent zones. They also have comparatively small leading edges, and the leading edge is the primary generator of lift preventing sideslip. Because of that they need a lot more surface area to generate the same lift. Surface area equates to drag so they need more sail area to achieve the same speed. Long keels tend to be less efficient in terms of lift to drag for other reasons as well...."

You also ask about the "Practical effect on speed." Jeff says: Surface area [of the keel] equates to drag so [full keels] need more sail area to achieve the same speed.

In discussing fin keels, Jeff says: "Fin keels...have less drag as explained above so they typically make less leeway and go faster."

There's a lot of "meat" in Jeff's article. If you'll re-read it carefully, thinking about each of your questions as you do so, you'll find that he answers most of your questions.

With regard to the above two questions, let me take a stab at explaining the general principles in a little different manner. A boat with a large amount of "wetted surface" has more drag, and is therefore slower, than a boat with a smaller amount of wetted surface. Wetted surface is the amount of the boat's bottom, keel and rudder that are submerged in the water. (A racing hydroplane, to use an extreme example, usually runs with only it's prop, rudder and a few square inches of its hull touching the water. That minimizes drag, and enables it to use most of it's engine power to generate boat speed, rather than to push a large mass of water aside as it moves forward.) A full keel sailboat has more wetted surface than a fin keel, so a full keel boat will generally be slower than a boat of equal proportions (width of beam, waterline length, etc.) with a fin keel.

Generally, the faster a sailboat moves through the water, the faster it is capable of going, and the closer it is capable of sailing to windward. I like to say, "Speed begets more speed, and better pointing ability." As the boat's speed through the water increases, the surfaces of the keel and rudder become more efficient in generating lift, and that helps the boat point higher. The same is true of the ability of the sails to generate lift, as they move through the wind. An ultra-light racing sailboat can generate enough speed so that it can even rise up onto a plane, lifting part of the hull out of the water, and, when that happens, the amount of wetted surface decreases dramatically and suddenly, resulting in a dramatic and sudden increase in boatspeed.

I hope this helps.
 
#9 ·
Thank you all, this is a lot of good information; and I will re-read and digest it all in good time.

From what I am reading;

The fin keel, properly done, seems to be a generally good improvement over full keels? (Big Generalization)

Heaving To seems not to be as big a concern with fin keels as might have been alluded to elsewhere?

Speed is good, not just for racing.

Fin better for backing up; but the usefulness of that advantage is very user specific.

Fin vs. Full keel seems not a big enough issue to rule out an otherwise good boat based on that variable.

Thanks, I think I have enough to go on.

Fred
 
#10 ·
I happen to own both, and like both for their own qualities. Cruising-wise, the full keel offers more volume lower down in terms of stowage and tankage generally than the fin keeler, and frequently either has a skeg-hung rudder, or the rudder is supported at the end of the keel itself, an inherently stronger installation for steering (two points of support instead of one, and less chance of damage from impacts/grounding).

Full-keelers are invariably slower for the most part, but frequently have a higher "comfort" rating in heavy seas than fin keelers, and are less sensitive to weight in the ends, another consideration for the distance cruiser.

Perhaps a "compromise" design is the semi-full keel boat, sometimes known as "the cutaway forefoot" and commonly seen with "the Brewer bite", the space between the keel end and the skeg, as seen in many of the designs of Ted Brewer.

Really, it comes down to the type of sailing you intend to do...I like light-air, go-fast fin keelers, but I chose a full keeler for reasons beyond speed, and because I feel in the end, a full keeler has advantages apart from pure sailing qualities (although I have not been particularly disappointed in those). When recently in six-seven foot seas, which is biggish for Lake Ontario, I noticed the motion of the full keeler was far smoother than similar waves in my fin keeler, and while less "exciting", was also less exhausting...I could safely move about the boat without fear of sudden slamming.

To each, however, their own.
 
#11 ·
A couple quick points here.....The reality of all of this is that boats are a system. Properly designed as a system where the hull form, rig and appendages are all working together, a fin keel/spade boat will offer significant gains in speed and should offer no liability to motion comfort, seaworthiness or tracking, and may actually offer significant advantages in all cases.

Whether or not a boat has a fin keel has little bearing on whether the boat has a comfortable motion, slams in a seaway, how much it can carry or whether it can tollerate weight in the bow. That is more a product of hull form and keel/rudder shape decisions that full keel or fin keel.

But, and this is a big 'but', most fin keel boats were designed for coastal cruising or some racing and so prioritize performance and cost over seakeeping or motion confort. This means that it takes more time and knowlege to buy a fin keeled boat to go offshore. Since one of the few justifications for buying a full keel is going offshore, a larger percentage of full keeled boats are designed to be offshore cruisers. Often these boats are truely hampered as coastal cruisers so it really makes sense to ask yourself do you really need a full blown offshore cruiser.

When you ask about the speed difference, it is not just a simple matter of speed but also the percentage of time spend sailing. As an example, a few years ago I spoke to a fellow who single-handed a high performance 38 footer from South Africa to the Carribean. He averaged 150 miles a day and used less than 20 gallons over the whole trip (including going through the Duldrums). He left South Africa with a 55 footer which he described as a reasonably modern full keeled boat. As I recall he said that the 55 footer arrived something like 10 days later and used well over 100 gallons of fuel.

I do want to clarify one more point, Boats with a Brewer notch are an example of a long fin keel skeg hung rudder.

Jeff
 
#19 ·
I do want to clarify one more point, Boats with a Brewer notch are an example of a long fin keel skeg hung rudder.

Jeff
True, but I think performance-wise they are classed with the full-keelers. I also concur that the boat is a system, but we are speaking in generalities here, hence the lack of precision.

There is one other factor, of course: time. The full keeler doesn't HAVE to burn that fuel...it is perfectly capable of sailing, albeit generally more slowly, than the fin keeler. Of course, the full keeler tends to have more tankage, more water and more stores aboard.

If the fin keeler hits extended calms, it is possible to burn up all the fuel, drink the water and eat the food...and still be becalmed.

Similarly, it's said the fin keeler can "outrun" bad weather, while the full keeler can "endure" it.

Both statements are partly false: a fin keeler making 9-10 knots in front of a storm doing 25 knots isn't outrunning anything, and a full keeler that can't trail a drogue or heave-to properly is likely to come to grief.

So parts of the equation come down to skill, the real need to go at a particular speed, and the luck of the draw. A single sailor can take a twitchy Open 60 at 25 knots through the Southern Ocean, and some of the best dive sites are on ships deemed "unsinkable".

Let your skills and favoured style of sailing dictate your choices. Understand that there are very few boats below the millionaire class that feature fast, high-pointing fins, skegs and with capacious tankage, and there's a few full keelers that can move very smartly in most conditions.

I would say, however, that if you're in that much of a hurry to cross oceans, consider air travel. It's much, much cheaper and much, much faster, even than an Open 60...;)
 
#12 ·
Couple of points Ajari.

Maybe of no great relevence but one of the fin keels advantages is agility under power, particularly in reverse. If you have a look at the thread "Pilot House ??? " from yesterday you'll see the narrow passage I had to reverse Raven up to get out of the slip. Its probably about 40 odd metres and not much more than a single boat width yet with a fin keeler I can reverse straight out. It's as easy as reversing a car. Do that in a full keeler and Oh Mama ! They do not like reversing at all.

Our girl is a fin with spade rudder. If I had my preference it would be fin with skeg hung rudder. To me that is a damn near perfect compromise.

Obviously this is not a set rule but you will find that despite the full keel being slower than a fin this is often not the case when reaching under normal working sails.

At this point you start moving into discussion of ketchs, schooners and the like where theoretically they are slower than a comparative sloop but when you free her up a bit and slap on a mizzen staysail the ketch picks up her skirts and flies. Same applies to gaffers. The speed than an old full keel gaffer can achieve when on a reach can be quite surprising.
 
#13 ·
Simply from my observations, and not from any theoretical standpoint, if you'll be doing a lot of manuvering (in and out of slips, narrow channels, etc) a fin would be better. If you're passagemaking then the full would seem to work better. That though, is simply my opinion.

Currently at 34 12 22 N 77 48 01 W, Wrightsville Beach, NC
 
#20 ·
It's my opinion as well. Maneuvering in tight spaces under power is definitely clumsier with my pilothouse cutter, but I attribute this in part to my windage. Part of this is being addressed via the installation of a four-bladed feathering prop, which will be pitched in reverse to provide considerably more stopping power and less prop walk. The other way to address this is to go back to older methods of maneuvering in tight places via the use of spring lines and warping off the dock or wall. On moorings, you sometimes get better results sailing off than motoring, or by using a combination.

It's best practised on a sea wall with little else around at first, but warping can put the bow where you want it even in contrary winds, but like heaving-to and knowing when to reef, it takes real practice and every boat is different. In my case, I have to dock "blind" as I can't see the dock from the pilothouse, and I have to make sure I don't clip the davits of my neighbour (I have a slip at the end of a finger.) This is when a good set of fenders, some skill at aiming, and the faith in going into neutral and trusting inertia to keep you moving comes into play. My wife is no long-jumper, but she hasn't got herself or the mid-ship spring line wet yet.
 
#14 ·
I would second Valiente's post. I cruised off shore on a fin keel boat, and spent many years racing them. One of the things I made sure I had on my next blue water boat, was a full keel. Do I want to sail it into my slip? No. Is it a joy to back up? No, unless you want to back to starboard. Would I buy a full keel boat as a boat for just day sailing in and out of a tight marina? No. However, in my experience, off shore
cruising is about moving in straight lines for a long time, and the less squirrelly your boat moves the better. What ever helps the self steering do the work for you makes the passage so much sweeter.
I love racing boats, I just don't want to go offshore in one without a really good crew, and even then the goal is to get off the water as fast as possible.
Full keel boats track wonderfully, and take much less effort, in my experience, from the helm. My whole philosophy, and I don't think there is only one right answer, is to be comfortable with as little stress to the boat and crew underway as possible. So for me, full keel, ketch rig, center cockpit, and pilothouse are all parts of the same puzzle. So spread the load and enjoy the trip.
And as Valiente also points out, tons of storage space.
 
#15 ·
Jeff H,
Just a minor point but Ted Brewer likes to call that style a Brewer bite not a notch.
All the best,
Robert Gainer
 
#16 ·
The fin keel was an invention at a particular point in history. Like all new ideas the old timers considered it dangers and it didn’t catch on when it was first introduced by Nat Herreshoff. When Bill Lapworth used it in modern times it was a resounding success especially when combined with the then relatively new material called fiberglass. But it still meets with resistance and ridicule from the old school.

Both types have good and bad aspects to the design but each can be a good seaworthy design if designed and built correctly. The key question is how the overall package is designed. As I have said before a boat is a system and it needs to be designed with that in mind. To decide which type is suitable for your style of sailing requires you to make decisions that can’t be made using someone else’s preferences and prejudices. You need to sail on examples of each type and decide for yourself how you want to handle heavy weather, provisioning, boat handling and even maintenance. All of those things are very different for each type of boat. It’s always a good idea to discuss the differences and trade ideas but you need some experience of your own to be able to weigh the relative value of each point unless you are willing to blindly accept advice from people who may or may not know what they are talking about. But more then that because route planning, storm tactics and almost everything else is determined by boat type you need an overall understanding of the entire process to intelligently select a boat.
All the best,
Robert Gainer
 
#17 ·
Jeff H,
You say, “By the classic definition of a fin keel any keel whose bottom is less than 50% of the length of the boat is a fin keel.” You have used this statement frequently and its wording implies that it is a well know and published statement. But I can’t find any reference that defines it this way. This is a convenient definition but it would be nice to have something to cite when saying this. Where did this come from?
All the best,
Robert Gainer
 
#18 ·
Thanks Robert.

I agree, if I have learned one thing from my time on this forum is that no one can choose for me, and that just about every variation; be it rig, keel, hull style etc. is right for some circumstances, and disasterous for another.

When I ask opinions I am always happiest when responses include context; and that is what I have enjoyed most about everyone here. (with very few exceptions)

Until I have the opportunity to try these variations for myself; I will endeavor to learn whatever is possible from the personal experiences of others.

Thank you all for very eriudite replys.

Fred
 
#21 ·
We have had this discussion so many times.

I sailed a modified full keel, a Union 36, from Houston to Scotland. It tracked well, and was stable. It does not go to weather well, but no-one in their right mind would want to go to weather in an Atlantic breeze of any strength. It's awful, and beats the heck out of the boat, whatever the boat is.

Certainly, a deep fin leaves me standing in light airs, and out-points me every time, but in the rough stuff, downwind, watch that helmsman, correcting, and correcting. Upwind, neither of us want to do it anyway.

Also, the long keel inherently has to endure less stress... now I did not say force... I said stress. We don't snap off so easily. Often we're cast into the glass so we have no keel bolts. We are definitely slower but more stable directionally.

Give me the long keel, or modified full, every time...

http://s217.photobucket.com/albums/cc128/rockter/?action=view&current=wkcrinancanalsummer2007.jpg

Good luck, what ever you choose.

Rockter.
 
#22 ·
As for getting underway from a quay wall or a dock... If the Current and wind are nil, push off with a boat hook. Any boat up to 50' should be easy to do so. We did this with Navy launches all the time.
Think on how you want to move away from pier side, especially if you have a bow sprite, stern overhang or exposed rudder and other delicate equipment hanging off your stern.
The name of the game is: No matter what kind of keel you have; Practice you landings and underways on flotsams, jetsams and protected pier faces. And train you significant other in doing the same. You may be incapacitated for some reason or other, and the family or friends will have to bring your boat in to the dock.
 
#27 ·
Sensible advice. I usually push off "manually" with the engine in neutral...even a 15 ton boat can be moved by a 45 kg. woman who puts her back into it. If you've got a reasonable set of fenders out, it's hard to hurt your boat or others unless you are going too fast.

I attempt most of the time to aim the boat in neutral and coast to a stop. I'm a big fan of making hard turns or "S"-turns to bleed off speed so I am coasting to a dock at less than one knot. That way, the merest two or three-second shot of reverse will stop the boat dead in the water where I want to be. I always consider, however, that the main point is not to fully stop, but to get a good spring line on in a timely fashion. When I see my wife has jumped onto the dock with spring in hand, I leave the helm and go aft to hand her the stern line and then run forward. We customarily dock with four lines, and double the bow and stern lines if we expect high winds.
 
#26 · (Edited)
Wing this

Wing keels were injected into the mix as a means of gaining lift when constrained by draft. Anyone who sails the Chesapeake and it's gunkholes with a monohull is dealing with draft constraints regularly.

In the last eleven years I have experience with both the wing and fin designs on my own vessels. I've found the wing to work well sailing upwind, but one definitely pays a performance price from the unused wetted wing surface once the wing levels as you go off the wind. To compensate for this I don't sail the wing as deeply off the wind and that seems to help with VMG, similar to the racer that doesn't sail the extreme example of dead downwind in less than heavy winds.

As for grounding issues, I have come up with some interesting observations from my own groundings in the muddy Chesapeake. I find a grounded fin is easier to back out, whereas a wing is harder to back out but has another escape route not as easily available to a fin. I've discovered completely on my own that under power and helm a grounded wing can be precisely and easily pivoted deirectly towards deep water, and then "walked" off by slowly applying helm back and forth. A grounded fin is much less maneuverable.

Though shallower draft, a wing is most vulnerable to grounding when level and the fin is most vulnerable to grounding when heeled. I've grounded a wing when heeled under sail and as soon as I dropped sail, the wing leveled and I floated free. Another time I simply fell off the wind a little and the wing cleared as it leveled somewhat. Now if you ground a fin when heeled, the only way to reduce draft is to heel, but what if you're were already heeled ? I've been there and it's a tough one.

I've only called a tow boat once and it was for a fuel problem. However IF I did need a tow off of a grounding with my current wing keel, I'd insist as part of the contract that it be pulled off by towing somewhat side to side as I've done successfully using power and helm.

It's silly to simply brand a wing a bad grounding risk. Whether you've got a wing or a fin, you need to be aware of it's capabilities. Unfortunately for those inexperienced with wing keels, intuition doesn't bridge the knowledge gap. From Jeff H's towboat operator conversations, it sounds like the inexperience extends well into the towing fleet. Last year I read about a tow boat operator who spent a few hours trying to heel a wing off of a grounding !

Whatever you're sailing, don't ground at near high tide or you may really need that tow.
 
#30 ·
A fin or a full keel isn't going to have much effect at anchor, I would say. At dock, yes.

My 33', 9,200 lbs. fin keeler draws four more inches of depth than my 41', 29,500 lbs. full keeler. I've actually made use of those four inches to clear into docks with a measured six feet of depth...I draw about 5 foot 8 as currently laden.

It's really apples and oranges in some respects, though. I think a strongly built longish fin with a skeg-hung rudder is near ideal, but it's not the most popular design in the "economy bracket", possibly because it makes the hull mold quite complex.
 
#31 ·
Not thinkin' V. Of course I should have said tied up rather than at anchor. Daffier than normal today, big night last evening, teddibly teddibly drunk and paying for it today.

We agree on the fin/skeg business. I've always liked the look of the V40 underwater profile. Long fin with skeg. Should track pretty well, draft kept to a reasonable depth, nice solid skeg for protection. Hard to beat.
 
#33 ·
There's a few of them out there design-wise, favoured by Bob Perry and Ted Brewer and a few others. They make the boat more expensive, which is probably the biggest reason they aren't more popular, but also because they are slippy enough for the performance cruiser/racer types, who want fins and spades, and they aren't "trad" enough for those who want a Contessa 26 with a thyroid condition, or who think everything made since the Westsail 32 is crap.

Wrong. Boats have never been as good as they are today. Unfortunately, those great boats are very expensive! There's a lot of boats out there also that are too lightly built to provide a safe or endurable ride for cruisers who have to anticipate poor conditions at some point. Of course, the proportion of boat owners who actually get caught in real gales or worse is extremely small.

I am growing to appreciate the sailing qualities of my semi-new full keeler (undoing a hundred connections in the engine bay yesterday contributed to this), but I consider myself relatively clear-eyed when it comes to its shortcomings, or rather insufficiencies in terms of desirable attributes.

We got it to hold the gear, tankage and provisions necessary for both extended cruising off the beaten track, and for comfortable anchoring. It's a cross between an SUV and a mini-van at sea, in essence, but there's a lot you can do in a mini-van that would be very difficult to do in any other kind of vehicle. I suspect when all is said and done, I will in fact make passages as fast as any others, particularly if I stay out in heavier weather making distance when other lighter boats have to slow down or turn back. I'm not talking about storms or even strong gales, but the 25-35 knots that almost all cruisers are capable of handling structurally, but which can be quite uncomfortable if not exhausting for some crews in lighter boats to handle.
 
#35 ·
Of course, the proportion of boat owners who actually get caught in real gales or worse is extremely small.
But if you are the one to get caught out boat quality suddenly becomes very important.

I think there are more poorly made boats available today then ever before. At one time there was a clear distinction between day sailors and offshore cruisers but today lightly built unsuitable boats are being marketed as serious offshore capable boats. A lot of newcomers are joining the ranks of sailors and don't have enough experience or skill to see the difference so they are setting out offshore and having trouble in record numbers.
All the best,
Robert Gainer
 
#38 ·
Hmmm..Wombat's PB was full keel, albeit cutaway forefoot and I'd have hated to try and careen the sucker. Whenever we slipped we had to velly velly carefull to tie down the stern cos she was a tad tippy towards the bow.

The current Womboat is fin but balances on the hard beautifully. For peace of mind I'd move the anchor chain to admidships but other than that I'd be quite happy to careen her.

On the slip this week we had a line running from the bow and tied off to the cradle but it really was not necessary. (see image in the 40' Pilot house thread.)
 
#39 · (Edited)
Crazy Brit Newbie

Hello all,

Excellent information in this thread.
I have just joined the forum and if my question has been answered in previous threads I apologise.

This may seem a bit mad but I own a Hunter 19. (which is the smallest yacht ever to complete the single handed transatlantic yacht race) I want to cut her fin keel off !!!

It dates to around 1981 and has been well used by my kids and grandkids and shows the use and abuse. Paint and some TLC will fix all that though.

I have recently had open heart surgery and to be honest I think my sailing days are over. I am getting to the point where I neither want to launch her in deep water and moor her in a Marina or at a swing mooring. (which includes mooring fees) I could get a lot of use out of the old dear if I turned her into an outboard driven trailer / weekender / fishing boat and launch her in the shallow put in points on the Scottish lochs.

So , and thanks for your patience, what effect on the stability, safety, leeward motion, stright line tracking, righting capability etc would cutting the keel off have?

I would appreciate your thoughts and advice.

Many thanks
Y-team
 
#40 ·
First of all I assume that you mean a British Hunter Medina rather than what the Brits call a Legend and we Yanks call a Hunter.

But in any case, with all due respect, your plan makes no sense at all. Without a keel and a rig the boat would have a miserable motion, and be nearly impossible to move around. The low resistance hulls on sailboats make them extreme rollers once their roll moments of inertia get greatly reduced. Without adding ballast, the boat would be easy to capsize and have no good reason to right herself.

If I were in your position, I would sell the Hunter and use the proceeds plus the money that you would spend to remove the keel and rig and plug the holes,and modify the Hunter's trailer, etc. to buy a small cheap, trailerable power boat. The motion will be more comfortable and it will be far better suited to your goals.

Respectfully,
Jeff
 
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