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SeaKeeper vs Naid At Rest Stabilization

Discussion in 'Stabs, Tabs & Gyros' started by Gulfer, Feb 10, 2020.

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  1. Gulfer

    Gulfer Member

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    We have a Westport 112 with Naid At Rest Stabilization. However, I've been reading about the SeaKeeper systems. Very intriguing

    I know they Naid system works with big "fins" and the SeaKeeper uses a gyroscope. But, what's unclear can the guests really tell the difference.

    I'm sort of curious of the advantage/disadvantage to each system?
    Is it total over kill to have SeaKeepers in addition to At Rest Stabilization?

    Thanks for any feedback
  2. olderboater

    olderboater Senior Member

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    Westport has gone to using both on their larger boats. Only offer as option now on the 112'. There is a significant difference at rest but don't know if it's worth it to you. If you have guests getting seasick while at anchor, then likely worth it, at least to those guests. We don't anchor enough to go back and do it.
  3. mapism

    mapism Senior Member

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    Q1: in a nutshell (assuming equally good sizing, installation, etc.), gyros are a bit better at zero speed, and fins are better under way.
    Depending on sea conditions, fins can be MUCH better.

    Q2: Yes, sort of. Normally, boats equipped with both systems use only the gyro for zero speed and fins under way.
    Which means that you can fit non-zero speed fins, whose cost and system complexity is lower.
    But if you already have zero speed fins and you aren't happy with their performance at anchor, an additional gyro could make sense.
    One alternative worth exploring is the possibility to fit larger fins.
    If the rest of the existing components can handle them, that's a relatively inexpensive way of getting a better stabilization at anchor.
  4. Gulfer

    Gulfer Member

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    This question was more out of education...

    At the boat show, I saw SeaKeeper advertised everywhere. When we purchased a Southport 33FE it was an upgrade option. I choose to wait. While the gyro technology is fascinating it's not the cheapest upgrade.

    Just wasn't sure how while the system works for big boats.

    Do you know how many they put in? I thought 2 SeaKeepers, but I've also heard 3.

    I believe when I asked the Captain, he said our fins are pretty large. Don't quote me on this... as I tend to get things wrong. But, I think he said they were 3 feet.

    I know our system has worked pretty well for us. The only time we had a little issue with 'sea sickness' was anchoring out in Cuba. The wind was swirling; thus the boat was rocking back and fort, and drifting side to side. We were eating dinner... The movement became too much for my wife. We went up front and sat outside to get some fresh air. She wasn't feeling good, and looked over at me and said in a firm wife tone "And this is why I don't want to live on a boat!"
  5. Capt J

    Capt J Senior Member

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    I don't think having 1 uncomfortable day justifies putting in seakeepers on top of your zero speed stabilizers. 2 seakeepers tend to work better than 1 seakeeper and are easier to find a place for. Keep in mind on retrofits, you sometimes also have to re-inforce the area you're mounting it in. I don't think seakeeper would have made your 1 situation any better, because they too have to adjust to movements from different directions if the boat is swinging.

    That being said, does your Captain adjust the sensitivity settings of your current stabilizers to match different conditions?

    As for the Gyro versus fins argument......I have run LOTS of different gyro boats, several dozen of them......probably close to 50 different yachts, they're very good at rest and hull speeds in most sea-states except sometimes in a 1/4 following sea......they tend to keep the boat rolled over to one side for far too long before righting.

    That being said I run one boat with side power curved fins and have put several thousand miles on it and anchored a few dozen nights in different areas and anchorages, and they are better than the seakeepers in every single aspect, including on anchor.
  6. Gulfer

    Gulfer Member

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    Good to know... There is always "hidden" costs, once you do a deeper dive.

    So, is it fair to say, for "big" boats. If you only had to pick one, it would be FINS. From there, adding SeaKeepers is a "NICE TO HAVE"

    How about on a smaller boat, for example our Center Console?
  7. Capt J

    Capt J Senior Member

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    On a center console is they work well if you can handle the added weight and power draw, via either a generator or if going strictly DC possibly adding a couple of batteries so it can run while anchored for several hours or etc, without the engines running. I ran a 43' Tiara LS, with 3-425hp Yamaha's and it had a generator etc. The seakeeper worked really well on it. I also ran a 42' Tiara flybridge with a seakeeper and it worked very very well on that boat, even at cruise.
  8. Gulfer

    Gulfer Member

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    Ours is a 33ft Southport with twin 425hp
  9. Capt J

    Capt J Senior Member

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    Yes a properly sized seakeeper installed in the correct location would make a very noticeable difference at all speeds. Whether or not the expenditure is worth it to you and there is the room to install it is the other question.
  10. mike Hartley

    mike Hartley New Member

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    Capt J.....

    What size boat are you running with those side power ? You think they are pretty good at both speed and at rest? How fast have you run with them engaged?
  11. Capt J

    Capt J Senior Member

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    66' Sunseeker Manhattan (F.B.), we cruise at 27 knots everywhere, top out at 32 knots. They're amazing at speed and better than a seakeeper at rest. They help a little with the up and down bow motion as well as amazing with the side to side at rest and we anchor a lot. I usually run them dialed down a bit on the sensativity as they're that good. I'll send you a video of us crossing the gulf stream in 5-7 off the starboard beam at 27 knots. For your boat, fins would be better than seakeeper.
  12. mike Hartley

    mike Hartley New Member

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    yes...Im looking for fins....that would be great to see the video....we are getting numbers on Niaid, Trac and side power and looking at all the pros and cons..due diligence ...appreciate the insight.
  13. LuvBigBoats

    LuvBigBoats Member

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    Following up on this thread, has anyone here slept on a boat using vector fin stabilizers at zero speed and if so did you notice how noisy they were? Were the fins mounted with berthing in mind so that they were not right underneath a berth or does that not even make much difference noise-wise?

    Looking at options on boats I'm considering buying.
  14. Capt J

    Capt J Senior Member

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    Yes many times with the sidepower curved fins on a 66' Manhattan....they were mounted in the engine room forward. Never heard them inside the boat. Anchored in many different conditions, ran in rough weather both at hull speed and cruise speed. They're AMAZING. Better than a seakeeper at anchor and slow speeds. Better than normal fins at fast speeds........Never heard them over the generator in the engine room.......barely could hear the generator inside or outside of the boat, and never heard the fins, so couldn't tell you noise as we didn't hear any.
  15. olderboater

    olderboater Senior Member

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    The same experience here as Capt J had.
  16. LuvBigBoats

    LuvBigBoats Member

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    Thanks both. That's valuable info. Seakeepers on some of the boats I'm looking at are north of $200k. I assume zero speed stabilization would be significantly less.
  17. JustAzimut

    JustAzimut Member

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    I am also interested in this topic. Is there a ball park figure on the fins for a 75'+ boat?
  18. mapism

    mapism Senior Member

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    I'm not up to speed with regard to prices, but for retrofitting, I would rather go for electrical fins, which are drastically simpler and as effective as any hydraulic fins, if not better.
    This is the company that pioneered the system, by now well established among many high-end builders, and as I understand they also have now a US subsidiary in FTL.
    No personal connection with the company, other than having followed the installation on the Canados of a friend of mine, whose actual size is almost identical to your Azi - and she also has 4 side entries, btw... ;)
    You can check out here a short video that I made during the first seatrial, even before fine tuning the system further.
  19. JustAzimut

    JustAzimut Member

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    All of my research has landed me on this same thought process. Economically, Seakeeper solutions are a bit much to swallow.

    When we decided on the Azimut, size and stability were pretty far up on the list. The Mrs., does get a little queasy at times and knowing we were going to be in the Bahamas, on the hook as much as possible, a heavy/beamy boat is needed...specifically with our draft being what it is...not a lot of shore hugging available.

    I am tempted (the wallet isn't bottomless) to wait a full year to see if they are absolutely necessary but this is one of those things that I should probably get in front of...the whole, 'happy wife/happy life' scenario.
  20. JustAzimut

    JustAzimut Member

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    Whoa!! What a difference.