FULL verses FIN

[pjbsailing]

Awesome. Thanks Morgan Paul!

[Southern Star]

In terms of cruising boats, prior to my cat I have owned full keels (Folkboat, Alberg 30, Bayfield 32C) and a long fin with a skeg mounted rudder, well aft (Cartwright 36 Pilothouse cutter). I would not hesitate to go to sea with either arrangement.

With proper sail trim, my folkboat sailed a better course upwind than I could when helming (up perfectly in the puffs, off in the lulls, no rudder braking effect from unnecessary steering corrections). My Alberg 30 and Bayfield both tracked exceedingly well and could maintain an upwind course for a significant period without touching the helm, although the Bayfield required the wheel to be locked a couple of degrees to leeward. Neither, however, could handle extremely gusty conditions (nor close reaches) without some helm adjusment in the way that the Folkboat could.

My Cartwright proved to be able to track as well as either the Bayfield or the Alberg, and was much more responsive to the helm. Remember, all of these except the Bayfield have done successful circumnavigations, albeit not in my hands ( indeed, it is even possible that the Bayfield32C has circumnavigated - I just don't know of one). All were noted for their tracking ability and their 'sea-kindly' motion in heavy seas, although due to the higher beam/waterline ratio and lower relative displacement, the Bayfield did tend to get bashed around more than the others when sailing into heavy seas.

The point is that the ability to track well can be accomplished without a full keel, although the fin must be kept fairly long. Ted Brewer is generally credited with creating the 'Brewer bight' - this was, as it sounds, a full keel with a 'bite' ( a small semi-circular section removed from the keel just before the rudder). It is not to be confused with a long fin keel with a separate skeg mounted rudder. The purpose of the 'bight' was to reduce the surface area of the keel (and therewith some drag) and to improve the steering response in relation to a full keel, while maintaining good directional stability. Both designs achieve that to a varying degree.

Like directional stability (or 'tracking'), a 'sea-kindly' motion is just as possible in a boat with a (long) fin keel. According to Robert Perry, NA, the key issue is not 'U' or 'V' sections in the underbody, it is rocker (the fore/aft curvature) of the hull. It is the rocker that tends to keep a larger amount of the hull in contact with water when sailing in large seas. Here too a moderate to moderately heavy displacement helps, as does either a 'U' or 'V' shape to the underbody (flat is great in light monos for planing, but will tend to pound when sailing to windward in heavy seas).

The point is that the same desireable sailing attributes for extended cruising can be achieved with either fin or full keels, so long as the fin is kept fairly long and the underbody has adequate rocker and no flat sections to promote planing (or more commonly, greater interior space). Of course there are those (eg, the Dashews) who promote light, relatively narrow and flat bottomed boats for offshore - and they will certainly be quicker in most conditions. But I suspect that most people would still prefer the more tradional 'sea-kindly' motion and tracking ability of a heavier displacement boat with either a full keel, or a long fin.

Robert Perry designed full keel cruisers, although his preference was (and is) for a long fin with a skeg mounted rudder well aft. He believes that it provides the best compromise by maintaining a sea-kindly motion and good tracking ability, but with better helm response, better steering control in reverse and better pointing ability (even a long fin can be designed to provide some lift). His Valiant 40 paved the way for a whole genertion of 'performance cruisers' and the basic premise of the design still has huge merits for the offshore sailor.

Are spade rudders appropriate for a distance cruiser? They would not be my choice, although I can acknowledge the advantages of a balanced rudder in terms of steering response (and reduced effort at the helm). The problem is that there is still (and will always be) a greater tendancy to lose the rudder through contact with cargo containers, or logs or (?) than there is for a rudder hung behind the keel, or an adequate skeg. If the rudder post is made of carbon fiber, you are virtually guaranteed to lose the rudder with any significant contact (witness some Hunters who experienced lost rudders offshore). Even with a very solid, stainless steel rudder shaft, the best case scenario will result in a bend to the rudder shaft. Frequently this will completely disable the steering; indeed, it can be worse than no rudder at all if it becomes fixed in an off-center position (as is typically the case).

Another arrangement that has its proponents is a full shoal draft keel with centerboard. This can permit an even shallower draft than a full keel alone and better performance to windward. While not everyone's cup of tea (and recognizing that the added complexity of the centerboard is more apt to cause problems), it is a terrific compromise that is currently out of vogue. That such an arrangement is suitable for offshore passages was proven in the mid 1950's by a Sparkman and Stephens design that won the Marion to Bermuda race and various other offshore events. Sorry, I can't recall the name (although I am sure somebody out there can help me - she was quite famous.).

Anyway, I vote for all of the above. The issue revolves around your intended use (including the desire to gunkhole), the shape of the hull, the shape and length of the keel and the method of attaching the rudder. All are quite capable for offshore use so long as the boat was (well ) designed and constructed for offshore sailing.

Brad

[Sailormann]

Is there any credit in the idea that a fin keel will get you there faster, so you have less chance to be caught in a storm? or that you could out run a storm?

This could be a factor if you were sailing one of the Open Class Ocean Racers, but the speed differential between the average fin keel and full keel cruising boat is not substantial enough to use this as a deciding factor. If you want speed, consider a multihull.

[windshadow]

wow big can of worms

[Weyalan]

Originally Posted by Sailormann

This could be a factor if you were sailing one of the Open Class Ocean Racers, but the speed differential between the average fin keel and full keel cruising boat is not substantial enough to use this as a deciding factor. If you want speed, consider a multihull.

I don't believe that is quite true. I cruise an old 40' race boat, and we are significantly faster on all angles of sail than almost any 40'-ish crising boat. For example, a friend of mine has a lovely challenger 39, which, in 10-12 knots of breeze probably sails at least 2 knots slower than us at any angle of sail. Now; 2 or 3 knots mightn't sound like much, but if your intended anchorage for the night is 40-50 miles away, we will get there 3 hours faster then them, which might allow us to beat the nasty front, but them to not, or us to get throught he nasty shoals in daylight and them not...

Really, I don't have an axe to grind either way, but sailing speed certainly shouldn't be dismissed and you don't have to go to an open class ocean racer to get a significant improvement in speed.

[Joli]

Really, the best thing to do is look at race and rally results, if that is not available look at sisters that have made substantial jumps and what the average daily run is.

[rexposeidon]

No one seems to mention the more obvious point to a full keel (IMHO), safety aside, storage. Having own several fin keels, my "next" boat will definitely be a full keel, for the storage. Hard to make an ocean passage when you have all the extras stacked upon the deck, bunks, and any other space not otherwise occupied. Fin keels might be faster, but lack in the ability to carry the stuff I want with me.

[jzk]

"Having a full lead keel with only epoxy covering it, I would rather have it encapsulated! I have a few chunks of lead missing from my keel, which I have faired back in with epoxy. If it were glassed over it would be an EZer fix. Hand working with lead is a toxic job."

I had an encapsulated keel. I am not a big fan. I would rather be aground with a lead surface than the fiberglass because the fiberglass just crunches away. If you take chunks out of a lead keel, that would translate to more chunks of fiberglass.

[roverhi]

Radyon3, I've made the passage south from SanFrancisco to SoCal twice, both times could have easily stopped at Channel Islands on the third day. Did I have a lightweight fin keel boat?? No I was singlehanding a Wetsnail. That was without a vane, I had to drive the whole way. There are full keeled boats that will move and those that won't. Same goes for fin keelers as we embarrassed more than our fair share of supposedly hot fin keelers with our W32. If I was crossing oceans on a budget, I'd buy my old Wetsnail back and try and beat my 180nm, through the water, best days run and 118 nmpd average for well over 10,000 miles.

If my only intent was harbor hopping down the cost, almost any boat will work. A heavy full keeler will probably do just fine but will bore you to death. I've opted for something lighter and more 'fun to sail' to make the trip north to Alaska. For open ocean passages, however, I still don't want fun as that rhymes with exciting which could result in death. The ancient Chinese curse, "May your passages be interesting," comes to mind. For the long haul, you want a boat that will maintain a heading without fuss, have an easy motion, is hell for stout, and able to carry your world within. That's not a lightweight fin keel boat unless you start adding lots of feet to the length.

BTW, the Taiwan Turkeys are not noted for their sailing ability. Do you know they will actually surf backwards.

Aloha
Peter O.

[Randyonr3]

Peter O,
Boy thats one damn fast westsail 32 concidering its a full-displacement boat which falls under the catagory for that nasty word "hullspeed". Seems that your max hullspeed for that w32 is 7.03 knots and your 180 nm day gave you 7.5 average. not bad at all. and your average day of 118 nm would give you 4.91 or almost 5 knots average for 10 thousand miles. on a full displacement boat with a waterline of only 27' 6" and doing it all with only 630 sq. feet of sail area..
Well I got to hand it to you, your Westsail 32 is a whole lot faster than my boat, a cutter rigged First 42, designed and built for open ocean racing...
My hat is off to you Peter......................

[roverhi]

Actually did 180nm or slightly better on the Walker Log with three different W32s. Also covered 900 miles in 6 days in the in the North east trades. Of course, they wouldn't go to weather in light air with any chop to save their butts. Actually had a Cal 20 sail around us twice, complementing us on the boat while ghosting along off Huntington Beach. The vane was steering and my crew and I were on the cabin top enjoying a beer. Of course, no full keel boat will hang in there with a light, low wetted surface boat in winds under 5 knots and really need 10knots to come into their own. Still, once winds got much over 5 knots she'd do 4 knots and do it day in, day out.

Aloha
Peter O.

[over40pirate]

My full keel boat (with a cutaway forefoot0 heaves to just fine.
It also sails thru lobster laced waters, as if they wern't there. Picked up 3 pots in 7 years of full time cruising.

Once was in a boat yard doing the bottom, and a 40' or so, fin keel boat with, or, I should say, without, a spade rudder was towed in from the Gulf Styreem, after the rudder fell off! they were able to retrieve it. The rudder stock was aluminum tubing, about 3-4" in dia, with about a 1/4" wall thickness.
Sorry, but I can't remember the brand.
I also like not having to worry about keel bolts.
Just crossing an ocean, a fin keel would be fine, but most people cruising spend a little more time in shallower water than the pond.

[ssullivan]

Originally Posted by CharlieCobra

My boat is 46 yrs old, wood covered with C-Flex, 39'-4" and weighs 7 tons NET. She has a full keel with a cut away forefoot and sails in heavy weather like a dream. Backing with a crosswind is a tossup as to which way she's gonna turn. She has a mind of her own and prop walk only works about half the time. She'll do 6 knots in 8 knots of breeze and 8 knots in 50 knots of breeze, regardless of the waves, unless we're beating and tracks upwind to within 35* of apparent. I didn't think I'd ever like an old woodie till she found me and find me she did.

Cool boat!

However, I wanted to make sure you realize a boat can't "weigh" its net tonnage. Net tonnage is a measure of the interior volume of a boat and has nothing to do with its displacement. What's the displacement of the boat, so I can better understand the post?

[gonesail]

full keel is safer most of the time except when backing in the marina. as alan said the full keel tracks so much better than the fin except if you are racing. if the fin is bolted on then you have another set of problems. full keel has a nice bilge also.

[cooper]

Ah the General speaks often through these posts... that is General Lyzation. It is like a lot of other debate we have. My steel boat has a fin keel (by definition). But no keel bolts. Poured ballast and a lot of tankage. Surely the stuff that only a full keel would have ? My full keel (by definition) 30 footer has a cut away no keel bolts and only 40 litres of spare room. She is ballasted with steel punchings. She also has a spade rudder. Tracking ability ...with or without a skeg on a fin keel ? Just how long and deep is a fin keel ? A boat with chines that has a sharp hull angle at the keel ....will it track less than a full keel even though it has a hull shape that adds to its "keelability" ? Is a boat with a shallow draught and rounded bilge sections but a "full keel" going to track better ?
We all know that in reality the keel is one facet of the bigger picture. The whole under water profile needs to be taken into consideration. Further, balance of rig can make a huge difference to lee way. Point of sail, can make a huge difference to tracking. Add bilge and tri keels into the mix and then what ?

If you take logical extremes to the max you will get BASIC answers. But a boat built of those extremes may not be the one that you will be comfortable sailing. Everything else is down to individual examples and experiences.

For my two bobs worth ...if it is cruising that you are on about ..."modesty is a virtue"......not to much or to little of the important bits of any design.

...And as a final word...I dont like a boat that is more comfortable upside down.....

cheers