Adjustable Keel...

[ParadiseDreams]

Hello everyone,

I was looking at boat manufacturers online today and I stumbled across one which had an adjustable keel, which they call the Smart Keel.

To me this seems ingenious, but it's yet another system which can possibly fail (moving parts).

I'm curious if this is a common thing on boats? How reliable is it? Would people generally prefer this type of keel or stay away from it? Does it really transform the handling as much as they say? What are the general benefits/drawbacks?

Any input is greatly appreciated.

Thanks

[cal40john]

Their keel retracts for trailering or getting into shoals, not for sailing. The trunk is going to take up cabin space is a downside.

Google Hobie 33, Macgregor, Corsair Marine, and a host of other trailerable boats.

John

[mesquaukee]

There are a number of boats like that, some are a swing keel some are a dead vertical lift.
A lot of steel boats are built with the keel lifted vertically. They have huge lines attached to the keel as a safety should the lifting cable break.
The largest one I saw was 50 ft with a 20 ton keel used for research in the artic, it was schooner rigged.
In Quebec (and France) you can get a lot of magazines, in French of course, extolling their virtues. They are packed full of designs, etc.
There are a number of GRP production boats in the 40 ft range which have a swing keel.
It is an appealing idea as you can get into 3 feet of water, yet have a 10 or 12 ft keel when you want it.

[cal40john]

As mesquaukee points out there are boats other than trailerable that have some kind of retracting keel, I focused on trailerable because of the ad and didn't think of the others. Some of those are designed to be sailed with the keel up, typically for offwind.

I have a friend who loves, well yawls first of all, then centerboards. His previous boat was a Shaw 24, he now has a Morgan 34, both centerboarders. He likes thin water sailing and has been known to use his centerboard as a curbfeeler.

BWS_thinwaterboats_mar09

John

[ParadiseDreams]

cal40john, thanks for the link, that was very insightful. mesquaukee, thanks for your input as well. I spent some time learning about keels just to understand what my needs are (err... will be ).

From all the 'sales brochures,' as I like to call them, seems that a retracting keel or a swing keel offer all the upsides of having a stable boat which can go up wind and handle blue-waters while also going in the shallow water with none of the downsides.

Based on your input, I can now see that this is not a common feature on boats. My question is why? Is it price? Is the performance not as great as advertised? Is it a maintenance nightmare (if implemented 'correctly')?

I know there's more to it than just the glossy advertising... otherwise every boat would have one of these keels. So what are their drawbacks? What do you sacrifice (besides some space) when you go with one of these keels? What are the risks and how likely are they?

Thanks again

[RainDog]

It seems like these keels are also used on custom built, high-latitude boats.

Example: Expedition Sail - Sailboat Seal

[Therapy]

Originally Posted by ParadiseDreams

Based on your input, I can now see that this is not a common feature on boats. My question is why? Is it price? Is the performance not as great as advertised? Is it a maintenance nightmare (if implemented 'correctly')?

Price may have something to do with it, but most probably the boats intended use determines the type of design.

I don't know much about performance. Too much engineering for me to understand. Also I don't know the relationship between design expectations and real life performance.

Maintenance must be an issue but repair would be even more so.

It's a boat.
It's a trade off.

One concern that people have found is that many of the designs have a certain amount of "slop" and there can be times when there is a lot of unnerving noise created because of that. I don't know about it being a problem structurally but it is annoying.

I am glad there is no slop or noise or movement in mine. Well designed.

[ParadiseDreams]

Originally Posted by Therapy

Price may have something to do with it, but most probably the boats intended use determines the type of design.

This seems to be the benefit, you get a 'dual purpose' boat.

Originally Posted by Therapy

One concern that people have found is that many of the designs have a certain amount of "slop" and there can be times when there is a lot of unnerving noise created because of that. I don't know about it being a problem structurally but it is annoying.

I am glad there is no slop or noise or movement in mine. Well designed.

So based on what you said, the issue that's reported has to do with the design/execution, not the idea?

I'm surprised nobody can really answer my questions. Maybe I asked in the wrong section of the forum or maybe this is just a topic most aren't interested in.

I've noticed the shoal fin keel is pretty popular and seems to be the 'best of both worlds' as well. This is what I'm leaning towards at the moment.

Hmm... I'll just keep searching/googling and doing the research. Any additional input is always welcome .

[Therapy]

Originally Posted by ParadiseDreams

So based on what you said, the issue that's reported has to do with the design/execution, not the idea?


.

Apparently.

But using basic logic one would know that something with moving parts will have some "play" in it. No moving parts = no play.

[ParadiseDreams]

Originally Posted by Therapy

Apparently.

But using basic logic one would know that something with moving parts will have some "play" in it. No moving parts = no play.

You're right also less maintenance and less problems.

Even though I'm still interested in this topic from an academic standpoint, after talking to my friend who's sailed the world several times, it seems I'm just best off with a fixed keel for my purposes.

[Therapy]

Originally Posted by ParadiseDreams

for my purposes.

The key!

[SkiprJohn]

Aloha Paradise,
Here were your questions:
I'm curious if this is a common thing on boats? How reliable is it? Would people generally prefer this type of keel or stay away from it? Does it really transform the handling as much as they say? What are the general benefits/drawbacks?

Here are the answers: It is very common in boats that are trailerable and or go into very shallow waters. It is very common. It is very reliable. People who sail in shallow areas prefer them and those who want to trailer their boats prefer them. It does not transform the sailing characteristics to windward that much and provides extra speed downwind if you pull up the dagger or centerboard.
The benefits: You can go into shallower water than other boats your same size. You can haulout on a trailer with a shallow boat ramp. You don't need a crane or travel lift to haulout.
The drawbacks: More mechanicals to wear and break, harder to cover your internal daggerboard with bottom paint if it doesn't extend below the trunk. The clunk, clunk, clunk when you are going downwind and rolling with the waves.
You can see by the smart keel design that there is a cable that pulls the board up and lets it down. Cables can wear, corrode and break. There is a centerboard pin or bolt that can either break or wear an out of round hole in the bearing area.
Shoal draft is not the best of both worlds. They do not perform to windward as well as a deep fin. They don't go to windward as well and centerboard/shoal keel combination.
kind regards,
JohnL

[ParadiseDreams]

John,

Thank you for the information. Since I'm most interested in boats in the ~37-45ft range trailering isn't an option.

"Shoal draft is not the best of both worlds. They do not perform to windward as well as a deep fin. They don't go to windward as well and centerboard/shoal keel combination."

Sorry, I meant to say that shoal draft may be the best of both worlds for my needs. When I spoke to my friend he stated that his boat had a deep fin, but his goal was to go around the world which includes all kinds of weather. My goal is to stay in the Mediterranean, Caribbean, Aegean, etc. Now, I certainly have to cross blue water to get there, but he said as long as I time everything and don't care about when I go and take the trade wind routes(?) I can time it such that I don't really hit bad weather or wait bad weather out, etc.

I'm still learning, so I'm not 100% sure. One thing he did state was to make sure to look for a boat with a good stability ratio. He suggested that if a boat I'm interested in has a capsize angle of 120+ then I should be fine.

Anymore input you may have would be greatly appreciated.

Thank you!

[SkiprJohn]

Aloha Paradise,
I kind of encourage folks to stay in the 32-36 foot range unless you plan on lots of crew or a family sailing with you. A full keel in that size very seldom gets to 6' draft and you can find them from 4'6" to 6'.
Good luck in your search.
Try to go out sailing with as many folks as you can to get an idea of what you might want to purchase. I always recommend basic sailing courses if you are not already a sailor.
regards,