Seakeeper gyro report

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This is a follow up thread to my original thread earlier this year on where to locate a Seakeeper SK9 gyro in my Ferretti 630 boat here http://www.ybw.com/forums/showthread.php?476800-Where-to-locate-a-gyro&p=6045111#post6045111

Due to lack of time available, I had my boat delivered by a skipper in early May from Antibes in SoF to Ventura’s yard at Vilanova near Barcelona for the SK9 installation

The first part of the installation required the primary fuel filters to be moved to a new position further aft in the engine bay and for a grp bed to be moulded (according to a template supplied by Seakeeper) on which the SK9 would be mounted

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Fortunately because the engines on my boat are with V drive gearboxes and thus are under the cockpit rather than the saloon and because Ferretti build in a large removable panel in the cockpit sole, craning in and positioning the SK9 was relatively simple

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A seacock was installed on the port side the SK9 and the finished installation looks like this

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Ventura missed the original agreed delivery date of end May but that was partly because I asked them to carry out a few other jobs at the same time. They also slightly damaged the teak cockpit sole during the installation. However, I negotiated some compensation from them for the delay and the damage and overall I am very happy with the installation which seems to have been carried out very competently. The total cost of buying, shipping and installing the SK9 was approx. €80,000 excluding VAT

Due to the delay and other commitments at home, I wasn’t able to deliver the boat back to Antibes myself and employed the same skipper to bring her home. He was very complimentary about the effectiveness of the SK9 which was reassuring.

I have not been able to test the SK9 myself until this past week and here are my thoughts after a few days of cruising my boat along the coast of SoF

On the positive side

• It works, at least at rest. I have deliberately sought out what I would previously consider to be marginal anchorages with onshore swell and passing vessel traffic and it does what it says on the tin which is to substantially reduce roll. Eating on board at anchor is now a far less fraught affair because we no longer worry about bottles, glasses and plates flying off the table when some dickhead comes whizzing through an anchorage at 30kts
• Its very quiet. There is a distant whining noise if you listen hard but the noise of our generator (which on our boat is relatively quiet ) drowns it out anyway
• The controls are simple. One button turns it on and another button activates it when it has spooled up to speed. Simples. Not only that but momentarily turning off the AC supply, such as switching between shorepower and generator, doesn’t seem to faze it
• The performance of the boat seems unaffected even with half a ton of extra weight in it. By placing the SK9 in the position that Ferretti use for their ARG gyro which appears to be pretty much over the CoG, the trim of the boat has not been changed greatly and boat speed is pretty much as before

On the negative side

• Its stating the obvious but a gyro only reduces roll. It has no effect on pitching and whilst roll is reduced, you still feel the vertical motion of the boat as a wave passes underneath it. A gyro does not turn a boat into a totally stable platform
• It has increasingly less effect as speed increases. As the hydrodynamic lift of the boat increases, the stabilising effect of the gyro has less effect. At 20kts I cannot feel any difference in the behaviour of my boat with the gyro engaged and disengaged although I haven’t tested it yet in a big beam sea
• The generator is on all the time. The gyro needs AC power and in the absence of shorepower it has to come from the generator which, in my case, has meant that my gennie is running from the moment we leave the marina to the moment we get back. I have put 60hrs on my generator in less than a week’s cruising and that is not running it overnight at anchor. Luckily I had my gennie thoroughly serviced this year but if I was speccing a boat from new with a gyro, I would probably specify 2 generators in order to have a back up because with a gyro, a generator becomes critical
• The SK9 takes about 20 mins to spool up and be ready for operation. That means you cannot just switch it on when your anchorage starts to get a bit lumpy. Another reason why it and the generator has to be running continuously
• This is a tricky one because as far as I’m concerned this needs further investigation but after one trip with both aircon and gyro running powered by the gennie I found my main AC breaker switch tripped out which I have never experienced before on my boat. The gyro seems to consume about 10A when spinning but I guess when it precesses, the AC load increases substantially and this may have overloaded the breaker. As I say this needs further investigation
• In my case, by installing the SK9 in the position I have (which is the most logical position in terms of not affecting the trim of the boat), it has impeded access to several key components such as the V drive gearboxes, shaft seals and fuel tank valves. Also the cover of the SK9 feels very light and flimsy so I don’t feel confident leaning or stepping on it to reach components

So in conclusion, can I say that my SK9 gyro was a worthwile purchase? An almost unequivocal yes. It has already added greatly to our boating pleasure. But is it the definitive stabilisation solution? No not in my view. Until battery technology (or some other technology) catches up with the ever increasing AC load requirements of modern boats and it is possible to run a gyro overnight at anchor from an invertor/batteries, its not the perfect solution. On this subject I do wonder whether Seakeeper could offer a low power mode with reduced performance and allow it to be run overnight from an invertor
 
My experience is exactly the same and I would not have a boat without one. Has transformed life at anchor. Have been out where non flybridge boats bigger than mine (prestige 500) are rolling alot and i am almost still.

Second nature now to switch on gyro 30 mins before the off. Then once back switch off and let gennie cool down under no stress for 10 or so minutes before switching off. At anchor I do not hear the gennie or gyro unless I go into the master cabin.

Luckily my gyro sits under the gennie so has not impacted access to anything.

Low power mode is a good idea though!
 
He way to achieve low power mode I suspect is using multiple units and turning some off in calm seas. I don't know if the effect is logarithmic ( i.e. That 25% does 25% of stabilising or next to nothing )
 
The Seakeeper 30 works on batteries but I don't know if you can have multiple units like the Italian gyros
 
Thanks for the info Mike. I have sleipner sps 66 fins just installed in Febuary. So glad I did-for us its a must to have zero speed stabs- totally worth the money. My kids would refuse to come on boat (8 year old twins frightened if it rocks too much). But yes I`m running a genny now at all times at anchor (unless totally still water) and through the night- its a worthwhile compromise but my gensets could be quieter- can keep aircon on anyway.
 
Thanks for the info Mike. I have sleipner sps 66 fins just installed in Febuary. So glad I did-for us its a must to have zero speed stabs- totally worth the money. My kids would refuse to come on boat (8 year old twins frightened if it rocks too much). But yes I`m running a genny now at all times at anchor (unless totally still water) and through the night- its a worthwhile compromise but my gensets could be quieter- can keep aircon on anyway.

Hi silverdee, I was admiring your new boat as we left our berth yesterday! If youre on board come round to say hello. Mole Sud left hand side about 5 boats up, Ferretti 630 called Sumianda
 
If the gyro doesn't do much underway, or not much that you need, maybe you could start spooling up when you are approaching an anchorage so that you'd be ready to go when you actually wanted the stabilisation and save a few hours on the genset, at least?
 
If you have it use it .
In terms of genset use ,to me that's a none issue in the wider £££ sence .

A decision has been made and executed to spend N of € 100 K on a totally descretionary item ,cos you can .

If you were to start thinking of savings like being gentle on Geny useage for fear of a big bill or poor residues ( dought it )
Then €100'k would buy -you do the maths - a lot of meals -+ wine in Hotel du Roc and any other SoF shore side restaurant which many do a pick up n collect rib service too .
That what Mrs Porto said , she would rarther spend €100 K on , if the unstablised plates flying etc becomes an issue .

TBO August in the SoF is mad boat wise and I conceed ,boat wash due to the shear busyness was an issue more than ever , having just spent a month aboard .
But we just up anchored and carefully mindfull of wash slipped away somewhere else .
How ever I wish we could have proper glasses not plastics -but hey ho I can live with that ----just at the mo

Of course if we spot Deleted User @ anchorage I guess we could take a bottle over to his boat now ( only if I,am not driving later )
 
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If the gyro doesn't do much underway, or not much that you need, maybe you could start spooling up when you are approaching an anchorage so that you'd be ready to go when you actually wanted the stabilisation and save a few hours on the genset, at least?

Well it does have a beneficial effect if you stick to displacement speeds and for that reason I think it encourages you to cruise slower and save fuel. You can see that this is the basis for a man maths argument to justify buying a gyro;)
 
Well it does have a beneficial effect if you stick to displacement speeds and for that reason I think it encourages you to cruise slower and save fuel. You can see that this is the basis for a man maths argument to justify buying a gyro;)
That's one of the reasons why, when I began thinking to downgrade to a P boat (:p), I always assumed that I would have installed a gyro, rather sooner than later.
Now, I'm not so sure anymore that I'll do a lot of single digit cruising in the future, if the first experiences are anything to go by...
And as you know, zero speed (a very nice to have feature in general, and in SoF even more so than in many other places) ain't actually so critical for us.

Anyway, an interesting reading indeed, thanks for taking the time to post it.
Judging from the pics, it seems that they made a very good job, and on top of enjoying the result, I'm sure the upgrade will make the boat stand out, if and when you would decide to sell her.
Not that I pretend to teach you anything on man math arguments, mind! :rolleyes: :D
 
Having just been on Mike's boat today in Mala I can honestly say his gyro installation is wonderful. We where on board for an hour or so and it was quiet and very effective. Once we got back on our boat we couldn't believe the roll. Mind you Mala is always rolly!
 
Very valuable feedback! Thanks a lot for your time.

I should state that it is an important investment, which is more than 10% of the boat's value in your case. Having spent a year at the Cote d'azur and after various rolly nights at places like Villefranche, I can say that a stabilizer really changes the boating experience. However I don't see it that necessary for the seas in Croatia, Greece and Turkey, where you can almost always find a protected bay. This year my cruising area was Montenegro, Greece and Turkey. I was lucky to spend 80 nights at the boat until today this year, spread in several months beginning from January. There were only one or two days/nights that I would need to turn on the stabs, if I had it. So I see stabs as a bigger necessity for boating in Balearics, SoF, Italy, but not that much on the other North Med destinations. That is what I could add up as a comment for ones who are planning to have one.

I appreciate your pros and cons list, because it is difficult to be that honest even to one's self after deciding and paying for such a huge investment for the boat (may be the most expensive add-on nowadays). It is really very valuable feedback for the ones who are planning for a stab.
 
I should state that it is an important investment, which is more than 10% of the boat's value in your case.
Thanks I'll sleep well tonight knowing that!

So I see stabs as a bigger necessity for boating in Balearics, SoF, Italy, but not that much on the other North Med destinations.
Yes youre right. Had we stayed in Sardinia or Croatia I dont think I would have bought the gyro but here in SoF there are so few sheltered anchorages and so much vessel traffic that its almost essential
 
Mike, sounds great. Has it quelled any desire for a bigger boat? If so, that's got to be money well spent.

Good lord no, Pete. Like most everyone else on this forum I'm on Yachtworld most evenings dreaming:D
 
Interesting comments Mike.

I'd say on our boat there is a noticeable effect at P speeds in a beam sea, though certainly less than at rest, but of course it's usual to have everything stored away if you're expecting slightly rougher seas that you could still plane in, so rolling is less of an issue. As you say, the gyro encourages you to run at D speeds anyway, because you can eat, drink and relax on board underway. We spend 80% of our time at 8 knots now.

Yep, the need to run the genny is the main downside. I looked at the possibility of running the gyro from an EFOY fuel cell, but it wasn't really feasible, and it would take a substantial increase in battery capacity to run without the genny otherwise, then you need to run the genny to re-charge them. In practice, we find the genny is not too intrusive during the day, when the gyro is most needed due to vessel wakes, and we rarely run the genny and gyro at night (though it's a nice option to have, and I sleep like a baby with them both running). I think the generator is essential whether you have a gyro fitted or not, so i'm planning to look at options to fit a second smaller genny, but that's mainly driven by the need for battery charging at anchor.

I don't think the AC load increases substantially as the unit precesses, as the energy in the flywheel is built up over time, and spent in a series of short bursts. I think the motor draws max current during spool up. Not sure about the hydraulic dampers though, maybe that's the extra load you're seeing.

If the lid feels too flimsy to rest on whilst checking things behind it, then you could just neatly fit a piece of marine ply on top. My series 8 doesn't have the cover, so you could also probably remove it altogether if that made access easier, though of course you'd then need the gyro locked beforehand

I agree with yourself and Eren that a gyro would be less beneficial in some cruising areas. We spent two weeks in the Ionian last year, and there are very few mobos and therefore not much boat wake to deal with.

Did the installer tell you about anode replacement? The heat exchanger anode needs replacing very often, i'd start off at 3 month intervals and check for wear.
 
Hi Mike just comming back to you on yesterdays post--yes wandered past your boat a few times but ships in the night. We are only really there in school hols as the terrorists are still young- putting off sailing the world for quite a while. But will catch up with you at some point- happy boating til then.
 
I think the generator is essential whether you have a gyro fitted or not, so i'm planning to look at options to fit a second smaller genny, but that's mainly driven by the need for battery charging at anchor.
Yes it is but fitting a gyro makes it more essential and also means that it gets a hell of a lot more use which probably means its going to break down sooner. Yes a small emergency generator for battery charging would be a good idea

I don't think the AC load increases substantially as the unit precesses, as the energy in the flywheel is built up over time, and spent in a series of short bursts. I think the motor draws max current during spool up. Not sure about the hydraulic dampers though, maybe that's the extra load you're seeing.
Yes youre right. We cruised down to Porquerolle today which gave me the opportunity to really observe the AC load. On spool up, my gyro seems to use around 20A and then settle down to around 17A once the flywheel is up to speed. I didnt see any spike loads on the ammeter with the gyro precessing. I can only assume that the main switch trip I experienced was because we were running the aircon at the time and somebody decided to boil a kettle or something and the total load was very high

If the lid feels too flimsy to rest on whilst checking things behind it, then you could just neatly fit a piece of marine ply on top.
I'm going to live with it and just try to be careful!


Did the installer tell you about anode replacement? The heat exchanger anode needs replacing very often, i'd start off at 3 month intervals and check for wear.
No! Nobody has mentioned that. In fact I didnt even get a manual with the gyro. Thanks for the tip. I will investigate that
 
We are only really there in school hols as the terrorists are still young- putting off sailing the world for quite a while. But will catch up with you at some point- happy boating til then.

Pah! My stepdaughter and her partner have recently completed a cruise in a 40yr old 36ft steel yacht from Inverness in Scotland to Hobart in Tasmania with their 4 and 6yr old kids on board. Where there's a will there's a way;)
 
Did the installer tell you about anode replacement? The heat exchanger anode needs replacing very often, i'd start off at 3 month intervals and check for wear.

Thanks again for the tip, Nick. Here is my anode after less than 4 months in the water

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