Retrofitting stabilisers?

[Andy Cox]

Morning All,

I was just wondering what thoughts there may be out there regarding retrofitting stabilisers to a 45' Trader.

We cruise at displacement speeds, about 9 knts and she can have a quite uncomfortable motion in certain seas, particularly directly on the beam or quarter.

Cheers
Andy

 

[jimmy_the_builder]

You'll get nothing but love from the forum for this excellent idea, especially if we can have a thread following the retrofit :encouragement:

 

[rafiki_]

Have you seen Vas's thread on fitting stabs to his boat MiToS? You might also consider a gyro stabilizer which is probably an easier fit? As J_T_B says, you will get a lot of encouragement off this forum.

http://www.ybw.com/forums/showthrea...isers-retrofit-on-MiToS&highlight=stabilizers

 

[MapisM]

I was just wondering what thoughts there may be out there regarding retrofitting stabilisers to a 45' Trader.

Simply put, the difference that stabs can make on a boat like a Trader, particularly if used mostly at D speed, is like night and day.

 

[MJGH]

Someone who read a book during the summer will probably be along to explain why your hull is all wrong

 

[Andy Cox]

Judging from the responses so far, I feel I might have touched on a topical subject!

I will check out Vas's thread, as that looks very interesting.

Also, I can now see why all the Traders, say 50' plus seem to be fitted with them as standard, and I would totally agree with MapisM about the potential difference they would make to us.

My main concerns about a project like this would be the initial cost of acquiring a suitable set of stabs and finding the internal space to fit them.

MJGH, I'm intrigued by your reply and look forward to learning about the deficiencies in the Trader hull shape.

Thanks so far

Andy

 

[Hugo Andreae]

You might also want to check the latest (Nov) issue of MBY.

There's a feature about a chap who retrofitted Humphree electric stabilisers to his semi-displacement Horizon 78 due to relative ease of fitment and lack of space.

They do smaller fins for smaller boats too.

 

[IDAMAY]

Having owned both a 45 foot Trader without stabilisers and a 54 with stabilisers, I can confirm that the difference is nothing short of magical. You don't say which model of Trader you have but our 45 footer was a 42 Signature with a hard top. In a beam sea of any significance we found it necessary to increase speed to obtain some dynamic stability. This was, of course, at the expense of fuel economy! We did investigate the possibility of retrofitting fin stabilisers. It was probably technically just about feasible but the cost was prohibitive. Changing boats was a simpler and more cost effective solution.


I think others will confirm that gyro stabilisers are great at anchor but can't hold a candle to fins whilst underway. I am not aware of any Trader fitted with gyros but there are plenty around with various varieties of fins, albeit, as far as I know, none under 50 feet.

If you do go for a retrofit your story will make fascinating reading.

 

[Hardmy]

Our hulls might be very similar, I've got a 48' built by Kha Shing (=Montefino) which is known to build all Traders.

It happens a few times a year that I get a bit bored by some rolling. This is usually cured by more speed or a slight course change. Of course I already eyed up to fit stabs (like Bart or Vas of this parish) but I'd better change the boat altogether. It just doesn't make any economic sense. We cruised extensively the Adriatic, Ionian or Aegean seas the last couple of years and clocked thousands of miles and never any of us or our guests felt really seasick... Still, I'd be very interested to see you pursuing this idea, at least I could copy-paste what you are doing should I change my mind

 

[Portofino]

Someone who read a book during the summer will probably be along to explain why your hull is all wrong

Well it won,t be me .

Clue is in the title
Here it is for consideration

“Naval architecture of planing hulls “By Lindsay Lord

So it’s content is none applicable here .

Constructively would it not be more economic to go faster / change course to go semi D speed ?
I mean have you costed out the total spend for which ever version of retro fit stabs and seen how much fuel that would by on top of the 9 knot eco fuel burn rate?
It’s ride must stiffen up with speed , Q is is that enough ?

 

[IDAMAY]

Our hulls might be very similar, I've got a 48' built by Kha Shing (=Montefino) which is known to build all Traders.

It happens a few times a year that I get a bit bored by some rolling. This is usually cured by more speed or a slight course change. Of course I already eyed up to fit stabs (like Bart or Vas of this parish) but I'd better change the boat altogether. It just doesn't make any economic sense. We cruised extensively the Adriatic, Ionian or Aegean seas the last couple of years and clocked thousands of miles and never any of us or our guests felt really seasick... Still, I'd be very interested to see you pursuing this idea, at least I could copy-paste what you are doing should I change my mind

The later Trader 42s (as far as I know the only ones still in production) were, in fact, built in a mainland Chinese yard, not by Kha Shing. They also had a slightly different hull design but still with a propensity to roll!

 

[n.herring]

My aquastar 48 has fins and I would now not buy a boat without them, so much difference.

 

[Andy Cox]

IDAMAY, she's a 445 Signature, which has the integrated swim platform with the 'Sea Stairs' arrangement which we much prefer over the bolt on swim platform of the other models. We have an 11 year old with special needs and although he's physically active, his level of coordination can leave much to be desired and this is a much easier and safer way of getting him on or off the boat, either in the marina berth or from the dinghy or water taxi.

Portofino, we only have the 225 hp engine option, which I liked the idea of as a way of keeping fuel costs down, as I only ever anticipated cruising at around 9 knts. I haven't tried her flat out yet, but my guess is we would only get about 12, maybe thirteen knts at WOT. I clearly need to do some experimentation to see if I would get enough additional lift to ease the rolling.

My guess is that the retro fitting idea is going to be non starter from an economical point of view and we would be better off trying to find a 475 Sig already fitted with stabs.
Cheers
Andy

 

[silverdee]

Hi Andy. Yes stabs make a total change to comfort on a yacht such as yours. Winter `15 we fitted sleipner sps 55 zero speeds to our then 52 foot flybridge boat and then bought an aquastar 74 and fitted the 66`s.
They are just fantastic but acknowledge its a v big job. Did mby articles both times. V expensive but for us it means the kids will in fact go on holiday on the boat. the zero speed function is amazing when having lunch or sleeping at anchor. There is some sense in you seeing if you can trade up to a boat with `em. To my mind older generation stuff (non zerp speed era) is now not really worth considering- both our boats had stabs the 52 footer 1976 vintage vosper mini-fins -they helped but could be overpowered in big seas and the aquastar koop-nautic tiny little fins- ornaments.

 

[MapisM]

My guess is that the retro fitting idea is going to be non starter from an economical point of view and we would be better off trying to find a 475 Sig already fitted with stabs.

By and large, it's true that it makes more sense to have stabs factory installed if possible, but I wouldn't dismiss the idea of retrofitting them, either.
Nowadays, electric fin stabs are available also for sub-50 feet boats, and also 24V DC powered.
Retrofitting them is still a job requiring some competence, but certainly less tricky compared to the installation of any older hydraulic system.
Besides, more than likely any 475 Sig with OEM stabs would have Wesmar non-zero speed stabs, which ain't exactly among the best of these equipments.
Bottom line, if your current boat suits your requirements nicely and you don't see any other advantages in replacing her with a 475, I would definitely invest the upgrade difference in a retrofit of a much better, electric driven zero speed equipment.

As an aside, the fins placement is crucial, and even builders can make mistakes in this respect.
Actually, I can't be positive about the the 475, and in fairness, when I seatrialed a T575 with OEM Wesmar fins, they were reasonably effective.
But some time ago, Silverdee of this parish bought a used Aquastar 74 whose original fins were placed too much astern, making the boat "fishtail" while cruising. So, when he replaced the old non-zero speed equipment, he also moved the fins position further forward.
A job which is practically as complex as retrofitting stabs on a boat originally built without them…

PS: Ops, I began writing all this before Silverdee posted his comment above, but I got a phone call in between and eventually posted my comment before reading his. Obviously he can confirm and/or correct what I said as appropriate!

 

[IDAMAY]

I agree that zero speed stabs are the way to go. We have earlier ABT-Trac fins but they are sized to optimize use at up to 9 kts. Their performance is amazing but they can very occasionally be overwhelmed by a quartering, following sea. If you are interested in pursuing a retrofit, Golden Arrow Marine, Southampton are the UK agents for ABT-Trac. They really know their stuff and were very helpful with the single maintenance issue we have had in three seasons use.





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[BartW]

here are links to reports from our retrofit project of CMC electric zero speed fin stab's, for inspiration,
http://www.ybw.com/forums/showthread.php?509494-Retrofitting-stabilisers
http://www.ybw.com/forums/showthread.php?295561-Blue-Angel-(Canados-70s)-Rebuild-thread (see index on first post)

although the system is very small, CMC now has a even more compact system aimed at 50ft-isch boats
the upgrade was done in 2013, and after 5 seasons of use, we are still very satisfied and couldn't do without them !

 

[MapisM]

CMC now has a even more compact system aimed at 50ft-isch boats

Yup, and that's the system available also as DC powered, hence not requiring any inverters.
I understand that also Humphree offers a similar product, but while I have no clue about the price differences, AOTBE I'd rather stick with CMC, if nothing else because their experience on electric stabs is second to none, having invented them! :encouragement:

 

[Deleted User YDKXO]

You might also consider a gyro stabilizer which is probably an easier fit?

It might be an easier fit but as you might remember I fitted a Seakeeper gyro into my boat last year. Its fine for stabilising roll at anchor but under way it has increasingly less effect the faster you go. Certainly at 9kts in my boat it has little effect. For stabilisation underway, fins are the only proven way to go.

 

[Will_M]

Golden Arrow Marine, Southampton are the UK agents for ABT-Trac. They really know their stuff and were very helpful with the single maintenance issue we have had in three seasons use.

For info to the original poster; Golden Arrow Marine are also the UK agents for Humphree, the go to place for fin stabs.