Nordhvn 51 Stabilisers

Nigel52

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My brother in law in Phuket is buying a Nordhvn 51 and needs advice on stabilisers. It looks like between CMC & Humphrey’s.




i am told that we should be able to install electric Stabilizers on board your N 51. Drew has provided two manufacturers that we could use, CMC and Humphree. See the attachment for the CMC’s and the link below for the Humphree. Also, per Drew’s comments below, he estimates the CMC up charge would be about $ 25,000 more and the Humphree could be and additional $ 10,000 to $ 15,000 above that. Please let us know if you have a preference as to which stabilizer manufacturer you would like to


Here is CMC. I don’t know what model Humphries we would use. I need to get that from the yard.



Humphree website: https://humphree.com/boat-fins-and-stabilizers/
 

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jfm

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Humphree and CMC are similar. They have flat fins made in two pieces joined together, and they use a catalogue electric motor/gearbox bought off the shelf from others. Both brands are good (not great) quality and widely used. Fleming have been fitting Humphree for a few years, for example. As a broad comment, Humphree seem to have put more effort into R+D over the last few years judging by the fact their product now seems considerably better than it was 5-10 years ago (when it was awful IMHO). I don't particularly like Humphree's management folks, but the product is decent. CMC seem to have done very little development recently and the product is perfectly good but is 10 years old in design.

The sleipner electric stabilisers are in another league, and are far far better. The gearbox is harmonic (so you can get say 500:1 reduction from just two similarly sized gear wheels), made by sleipner themselves, and is an engineering work of art far superior to the normal reduction gearboxes used by the others. The electric motor is another work of art, made by Sleipner themselves for this application. The whole actuator mechanism is vibration insulated from the hull by being mounted on a clever rubber mounting - it's a thing of beauty engineering-wise. The fins are far more advanced, being very curved and also cut away from the hull as shown in the links in post #3, and furthermore are moulded in one shot so there's no joining of two separate pieces. They are rightfully as bit more expensive, and in shorter supply right now than the others (because it is a newish product launch), but the product is far superior product in every way.

The 4th brand is Praxis. They are flat fins and look a bit last-century to me, and have no special features worth mentioning that I can see

On a new build Nordhavn (which isn't a project I would do :)) I would insist on Sleipner. But if you can't get Sleipner or don't wish to insist on them (and Nordhavn might resist due to not fitting them regularly) then I would get Humphree when I look at the market today for electric fins, which is basically Sleipner, Humphree, CMC and Praxis in that order.

All imho.
 
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Nigel52

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Humphree and CMC are similar. They have flat fins made in two pieces joined together, and they use a catalogue electric motor/gearbox bought off the shelf from others. Both brands are good (not great) quality and widely used. Fleming have been fitting Humphree for a few years, for example. As a broad comment, Humphree seem to have put more effort into R+D over the last few years judging by the fact their product now seems considerably better than it was 5-10 years ago (when it was awful IMHO). I don't particularly like Humphree's management folks, but the product is decent. CMC seem to have done very little development recently and the product is perfectly good but is 10 years old in design.

The sleipner electric stabilisers are in another league, and are far far better. The gearbox is harmonic (so you can get say 500:1 reduction from just two similarly sized gear wheels), made by sleipner themselves, and is an engineering work of art far superior to the normal reduction gearboxes used by the others. The electric motor is another work of art, made by Sleipner themselves for this application. The whole actuator mechanism is vibration insulated from the hull by being mounted on a clever rubber mounting - it's a thing of beauty engineering-wise. The fins are far more advanced, being very curved and also cut away from the hull as shown in the links in post #3, and furthermore are moulded in one shot so there's no joining of two separate pieces. They are rightfully as bit more expensive, and in shorter supply right now than the others (because it is a newish product launch), but the product is far superior product in every way.

The 4th brand is Praxis. They are flat fins and look a bit last-century to me, and have no special features worth mentioning that I can see

On a new build Nordhavn (which isn't a project I would do :)) I would insist on Sleipner. But if you can't get Sleipner or don't wish to insist on them (and Nordhavn might resist due to not fitting them regularly) then I would get Humphree when I look at the market today for electric fins, which is basically Sleipner, Humphree, CMC and Praxis in that order.

All imho.
Thank you for your response. I must admit if it was me for a new design boat I would want a minimum of 6 months use near the Turkish builders before shipping it to Phuket. Hoping that is what my BIL decides to do.
 

MapisM

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near the Turkish builders
Turkish? I obviously lost the plot on Nordhavn.
From one of the finest and more experienced Taiwanese builders to mainland China, and now Turkey.
Constantly hunting quality regardless of cost, those folks at PAE... :p
 

acbruce

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I thought that the thing about the Nordhavn 41 and 51 was that they were production style , complete with stabilisers and electronics, for a set price. I assume that the standard stabilisers are hydraulic. Why does your brother-in-law want to vary the standard spec? Just interested in the thought process as I have always liked Nordhavn although mostly the older type custom ones.
 

jfm

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Turkish? I obviously lost the plot on Nordhavn.
From one of the finest and more experienced Taiwanese builders to mainland China, and now Turkey.
Constantly hunting quality regardless of cost, those folks at PAE... :p
Yup Nordhavn 41 and 51 (new models) are built in Turkey. Obvs contract manufactured, not actually built by Nordhavn, and I know we both have the same thoughts about that.
 

jfm

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I thought that the thing about the Nordhavn 41 and 51 was that they were production style , complete with stabilisers and electronics, for a set price. I assume that the standard stabilisers are hydraulic. Why does your brother-in-law want to vary the standard spec? Just interested in the thought process as I have always liked Nordhavn although mostly the older type custom ones.
I would very much expect the standard spec is electric not hydraulic - humphree or CMC.
 
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