The perils of Stabilizers

[FF]

Probably the simplest way to get a sea kindly offshore vessel is to purchase a big motor sailor.

 

[AusCan]

Probably the simplest way to get a sea kindly offshore vessel is to purchase a big motor sailor.

Not quite as simple to operate as active fins or gyros, but certainly the cheapest option. Backup propulsion included at no extra charge.

 

[psneeld]

Not quite as simple to operate as active fins or gyros, but certainly the cheapest option. Backup propulsion included at no extra charge.

I would consider a motorsailor if there ever is a next boat.

With mechanical help, the work is simplified and if you know how to sail...you are almost home.

 

[caltexflanc]

Hydraulic fin stabilizers get their power from a pump mounted to one of the main engines.
DC power is used to activate the solenoids. All in all I found my Naiads pretty simple to maintain, though unlike a few other owners I know who could easily DIY the whole system , I left maintenance of the seals to professionals.

I have to admit if I was spec'ing out a new, money-not-much-of-an-object boat. I'd go with Seakeepers powered by a small 2nd "night generator", due to their really superior low/no speed performance.

 

[Comodave]

The gyro systems are very intriguing since you could use it at anchor. A couple of weeks ago we were in a harbor for 4 nights that would have benefited using a gyro tied up to the dock. How hard was it to modify the boat to install the Seakeeper? Which one went in your Defever? Do you mind telling us what it cost installed?

 

[Fletcher500]

Hydraulic fin stabilizers get their power from a pump mounted to one of the main engines.
DC power is used to activate the solenoids. All in all I found my Naiads pretty simple to maintain, though unlike a few other owners I know who could easily DIY the whole system , I left maintenance of the seals to professionals.

I have to admit if I was spec'ing out a new, money-not-much-of-an-object boat. I'd go with Seakeepers powered by a small 2nd "night generator", due to their really superior low/no speed performance.

I have never seen a second night generator on a boat (in the 40 to 50 ft. range at least). I haven't looked for awhile, but I believe the draw of a Seakeeper is around 2.5KW, so a small 7-9 KW gen will be fine. These size gens are not burning much fuel and are social engines, so I cant see how adding a second gen would gain much.

I suppose it would if you were talking about a very large boat with a big gen?

 

[caltexflanc]

We once chartered an early 80's 49' Grand Banks Classic that had a 4kw 2nd generator. The main genny was a 20kw if I recall correctly, or maybe a 15? You start running a bunch of AC, battery chargers, electric appliances and what have you and you can run out of KW pretty quick. Or be faced at night with running a couple of ACs off a big bruiser.

My boat was a 56' and came wired and paneled for a 2nd generator, as did several 53's.

 

[GGroves]

The gyro systems are very intriguing since you could use it at anchor. A couple of weeks ago we were in a harbor for 4 nights that would have benefited using a gyro tied up to the dock. How hard was it to modify the boat to install the Seakeeper? Which one went in your Defever? Do you mind telling us what it cost installed?

We purchased a Seakeeper 6, based on the sizing recommendations from the factory. The modifications were straight forward; they beefed up the engine room floor stringers on the side where the Gyro unit was to mounted with structural laminated wood boards the size of the stringers. On top of this base, they used a strong adhesive to bond a 1 inch thick aluminum plate with holes predrilled and helicoiled to mount the unit. All this was glassed over with seven layers of fiberglass, gel coated and then painted with Interlux bilge paint.

 

[BerettaRacer]

Hydraulic fin stabilizers get their power from a pump mounted to one of the main engines.

I have to admit if I was spec'ing out a new, money-not-much-of-an-object boat. I'd go with Seakeepers powered by a small 2nd "night generator", due to their really superior low/no speed performance.

On larger yachts it's the norm these days to install "zero speed" fin stabilizers. And they are operated by electric motor driven hydraulic pump.

 

[BandB]

On larger yachts it's the norm these days to install "zero speed" fin stabilizers. And they are operated by electric motor driven hydraulic pump.

There is another trend growing too and that is installing both fin stabilizers and gyro stabilizers on larger boats, the best of both worlds available.

As to generators, there are two thoughts. One is to have the second generator about half the kw of the first one. The second is to have two equal interchangeable generators.

 

[sunchaser]

In the hundreds of anchorages available in the PNW from Tacoma to Glacier Bay the need for zero speed stabilizers is virtually nil. In SoCal and Mexico it is a different story. I have found the East Coast a similar mixed bag with the various islands getting pretty roley.

So here is the question, why zero speed stabilizers for NA waters?

 

[BandB]

In the hundreds of anchorages available in the PNW from Tacoma to Glacier Bay the need for zero speed stabilizers is virtually nil. In SoCal and Mexico it is a different story. I have found the East Coast a similar mixed bag with the various islands getting pretty roley.

So here is the question, why zero speed stabilizers for NA waters?

As you said, some waters might need them plus from South Florida most of us travel to the Bahamas and to the Keys and some of us also travel in the Caribbean. Now, in our case, we anchor very little compared to many so the need is still questionable. That's a reason on our Loop boat we love the Sidepower Vector Fins in that they're good at anchor but a little simpler in design than most zero speed stabilizers.

 

[Bigsfish]

I think there is an advantage to have both fin and gyro stabilizers, cover all the bases. If I cruised more than one month at a time I would like two generators of the same size and brand.

 

[rsn48]

What I don't understand, just going by the pictures and assuming the water conditions I see in the pictures were the same when the boat struck the whatever. Why were the stabilizers deployed? I think crappy water conditions, deploy the stabilizers. And why were they deployed in a narrow channel?

 

[Bigsfish]

Unfortunately the fins are exposed even when not engaged.

 

[sunchaser]

RSN
Obviously avoiding a grounding is a good idea. Far more than stabilizers are at risk. In the case of the KK42 possibly it was a composite hull below the waterline. I know, details details.

 

[catalinajack]

Growing trend? Our 1983 DeFever 44 came with two factory-installed generators, a Perkins-powered (4.108) 12.5kw Kohler and a 7.7kw Westerbeke. We use the smaller, more quiet generator for lighter loads. I like the versatility of two differently sized units, and the redundancy.

There is another trend growing too and that is installing both fin stabilizers and gyro stabilizers on larger boats, the best of both worlds available.

As to generators, there are two thoughts. One is to have the second generator about half the kw of the first one. The second is to have two equal interchangeable generators.

 

[BandB]

Growing trend? Our 1983 DeFever 44 came with two factory-installed generators, a Perkins-powered (4.108) 12.5kw Kohler and a 7.7kw Westerbeke. We use the smaller, more quiet generator for lighter loads. I like the versatility of two differently sized units, and the redundancy.

I didn't claim the generators was a growing trend, just the gyro and fin combination.

We always have had two generators and use one or both. When we did the loop, we only used one and it seemed silly to have two. However, by alternating use, at least we were able to keep hours within reason.

 

[Flatswing]

Early model KK’s were cored below the waterline as I understand it. The fins are designed to snap the shafts off below the seals. It was proposed that the aftermarket installer sealed the core but didn’t remove sufficient coring around the large mahogany blocks that are glassed onto the inner skin and then through bolted with 5200. When this boat got pushed into the rock ledge due to ferocious current in the TSW, the entire stabilizer-fin, block & hydraulic ram tore away since the surrounding cored hull was the weak link.

 

[BandB]

Properly designed and installed stabilizers will not be the cause of your sinking. Poorly installed aftermarket or even OEM can lead to water ingress. However, when the job is done right, they won't be your issue. Go back to worrying about your shafts or about hull puncture.

 

[catalinajack]

Ah, sorry, the written word is often misinterpreted, at least by me.

I didn't claim the generators was a growing trend, just the gyro and fin combination.

We always have had two generators and use one or both. When we did the loop, we only used one and it seemed silly to have two. However, by alternating use, at least we were able to keep hours within reason.

 

[BandB]

Ah, sorry, the written word is often misinterpreted, at least by me.

'Tis fine. Glad to hear you like your two generators. Do wonder why your builder went with different brands though.

 

[BandB]

In the hundreds of anchorages available in the PNW from Tacoma to Glacier Bay the need for zero speed stabilizers is virtually nil. In SoCal and Mexico it is a different story. I have found the East Coast a similar mixed bag with the various islands getting pretty roley.

So here is the question, why zero speed stabilizers for NA waters?

Ferries going by regularly might be enough reason for zero speed from Tacoma to Glacier Bay.

 

[sunchaser]

Ferries going by regularly might be enough reason for zero speed from Tacoma to Glacier Bay.

Can't say ferry wakes have ever bothered us. North of Nanaimo ferries are few and far between. The worst rolly anchorage was Tribune Bay on Hornby Is when a gale 50 miles southeast blew up the Straits, creating swells like we've encountered in Hawaii.

 

[Portage_Bay]

Ferry wakes are not much of a nuisance. The bigger problem is wakes thrown by SD boats.

Ferries going by regularly might be enough reason for zero speed from Tacoma to Glacier Bay.

Can't say ferry wakes have ever bothered us. North of Nanaimo ferries are few and far between. The worst rolly anchorage was Tribune Bay on Hornby Is when a gale 50 miles southeast blew up the Straits, creating swells like we've encountered in Hawaii.

 

[Matt]

I advise against drawing any conclusions without more information. For what little it is worth, I have been around the world and then some on vessels with active fin stabilizers with no mishaps and on a number of vessels with cored hulls. These are not unusual and like every aspect of any boat there are plusses & minuses to consider, but nothing to condemn them for...

 

[BandB]

Ferry wakes are not much of a nuisance. The bigger problem is wakes thrown by SD boats.

And what about the wakes when we followed in an SD in the wake of the Ferry?

It doesn't take a lot of disturbance to make you glad you have the zero speed stabilizers.

 

[Portage_Bay]

And what about the wakes when we followed in an SD in the wake of the Ferry?

I'm not sure I understand your point or your question. The reason ferries are not much concern is that for the most part due to their routes they don't impact anchorages. Of course there are some exceptions. If you anchor out in Friday Harbor you will get waked by the ferries. But in my experience it is the SD boat at high speed throwing big wakes as they pass close by anchorages that are the issue.

 

[markpierce]

Try turning into the ferrys' wakes with throttle at minimum. Works for me. ... But I've a motor boat and you all have sailboats, often running an engine?. Still, that maneuver usually worked for me as it did on my previous not-operating-engine sailboat.

 

[BandB]

I'm not sure I understand your point or your question. The reason ferries are not much concern is that for the most part due to their routes they don't impact anchorages. Of course there are some exceptions. If you anchor out in Friday Harbor you will get waked by the ferries. But in my experience it is the SD boat at high speed throwing big wakes as they pass close by anchorages that are the issue.

Part of our trip up we just pulled in behind the Ferry and followed. I don't remember exactly how long, but for several hours. I'm sure the two of us did make sizable wakes but ours mostly lost in theirs.