Blue Angel (Canados 70s) Rebuild thread

[BartW]

I was suprised how much extra materiel was required for the hull stiffening for the stabs.

well purely for strength, this is probably much too thick,
but the thickness is determined by the height between the stab flanges (78mm)
so we needed 78mm total thickness anyway.

some brands make this with a inner soft coring, (except for the circle where the flanges are pressing)
but in my situation, (surfaces not really flat...) I preferred a solid plate of GRP or Epoxy
the extra weight doesnt make a difference on the total scale

the outside layup is needed for making height for the fins not to touch the spray rails nor the chines,
idea stolen from San Lorenzo,
other solutions, with inside layup only,
would require cutout from the spray rails, and placing the fins more towards the keel / center of the hull bottom

with my chosen solution, the electric fins can rotate 360°, never practically needed, but just in case, for maintenance or ...

 

[Pinnacle]

Thanks Pinnacle, They move a lot more than i thought they would.

Indeed........but as Bart has said, they are v effective.

Bart. Do you have an underwater vid of the stabs working that you could post?

 

[Beachcoma]

With the stabs do you have to centre them when anchoring and then start them again (in zero speed mode?!) or do you just leave them working?

 

[BartW]

I don't know how you did all that without pulling your hair out.

N,
I forgot to mention,
probably the biggest headache, and concern I had was making the right decisions between all the info and advice that I got in that period,
usually very good,
but sometimes very contradicting advice, from all advising party's:
- CMC the stab manufacturer
- The naval architect I hired for some advice
- the yard
- practical real live examples
- and last but not least, advice from forum mates on here,

answering important questions such as:
- how to do the hull reinforcement, construction wise,
- the best position of the fins
- the size of the fins
- and many small practical details

but thats all done now,
and luckyly the end result, thorroughly tested in the field, turned out to be very good.

 

[BartW]

Bart. Do you have an underwater vid of the stabs working that you could post?

there is one somewhere, tried to find it on this PC, but can't find it,
I believe one dive friend from the gang made it, tbc

 

[BartW]

With the stabs do you have to centre them when anchoring and then start them again (in zero speed mode?!) or do you just leave them working?

as soon as gear on one of the engines is engaged / dis-engaged, the fins go to the center and stop,
consequently, you can't manouver with the fins switched on

each time when you switch them on, you have to choose "at ancher" or "Navigation",
but
at anchor won't engage when speed is >2kn
navigation won't work when speed <4kn

depending on the speed, the maximum excursion of the fins is limited differently
this is all for security, to make the system totally fool proove

 

[BartW]

Thanks Pinnacle, They move a lot more than i thought they would.

at anchor they have to move the weight of the boat so they have to work hard,
but most of the time, they move a lot less then in this video.

during navigation, a lot less finn movement is required,
water flow forces on the fins are multiplied by the speed of the boat
in this mode the excursion of the fins is limited.

 

[MapisM]

When we were moored along a 90ft Princess in Monaco, and switched the UWL’s on,
The people on the Princess were ashamed with theirs,

Yeah, and here's why....

 

[MapisM]

Bart. Do you have an underwater vid of the stabs working that you could post?

P, they are visible in the clip below (already posted in the FDC thread), but just for a second, around 40".
In the original video they were surely visible for longer, but I'm afraid I didn't keep it after cutting this short clip.
Maybe scubaman or someone else kept the original gopro video? It was 3gb or so, as I recall....

 

[rbcoomer]

yes that was actually the first concern with them,
I hardly know anything about GRP placing,
but I could see that their method was not going to work,
so they ended doing many thin layers, instead of a few thick, just like you describe

the fins make a huge improvement to the behavior of the boat,
I have to say that we had any experience with fin stabs, but the wife, friends, and all guests confirm that they work very well
they work underway aswell as on anker,
even in our home port, there is a regular anoiing swell from passing tourists sideseeing and traject boats at too high speed,
so when we are onboard, the stabs are permanently switched on !

here is a clip made by MapisM, to demonstrate the effect of the stabs
first the boat is free floating in a swell,
at 18 sec, the stabs are switched on,

[/

Thanks - that's a very convincing example of what they can do isn't it! :encouragement: I did think they'd be used at anchor too given the use for diving - what a great setup.

Thanks Pinnacle, They move a lot more than i thought they would.

+1 Very impressive to see in action from beneath too

Yeah, and here's why....

What a great illustration of the quality of the Lumishore! They're on my list too...

 

[oceanfroggie]

Epic thread. Fantastic read. Don't know how I missed this one. Congrats on superb retro work. The results look fantastic. I presume on lift outs you have to be careful the guys driving the lifts know how to avoid the stabiliser fin.

 

[scubaman]

Yep, found the clip, you can see the stabs at work here:



Bart: a pretty impressive DIY job with pretty impressive results!

Again the swim platform rails work brilliantly making going into the water very easy, and perhaps more importantly keeping the heavy items where they can cause the least damage.

 

[BartW]

I presume on lift outs you have to be careful the guys driving the lifts know how to avoid the stabiliser fin.

yes, the guy's in Sanary took accurate dimensions, how and where to fix the boat on the lift-out trailer, for future use, (actually not too complicated)
but I'm not sure if I'll ever go back to that yard, but thats another story.

the yard that I have in mind for the next liftout have a big modern crane, with slings,
and even without the fins, they would have to use a diver, so I don't expect problems with that.
will need a liftout probably in februari or marsh, (small issue with the Hi lo platform)
Ill try to remember to make pics and post them.

 

[BartW]

Again the swim platform rails work brilliantly making going into the water very easy, and perhaps more importantly keeping the heavy items where they can cause the least damage.

perhaps some on here might remember, in the very beginning of this thread 2 y ago, there was a discussion about the usage of the hi lo platform for the divers,
and also about where to place the tanks, and not to damage the boat, .... orriginal idea was to keep the dive sets in the cockpit, as in the egypt dive safari boats,
but only by doing the upgrades step by step, and real live tests in between, this brilliant result (sorry to say this myself) came out of all the discussions.
f.e. the basic idea for the U brackets came from Elly after having used straps for fixing the dive tanks on the rails, during a previous dive week

 

[Deleted User YDKXO]

the yard that I have in mind for the next liftout have a big modern crane, with slings,
and even without the fins, they would have to use a diver, so I don't expect problems with that.
will need a liftout probably in februari or marsh, (small issue with the Hi lo platform)
Ill try to remember to make pics and post them.

Hi Bart, great report and I'm glad the CMC fins work fine. By coincidence, I was talking to a San Lorenzo guy today and they've had very good experience with the CMC fins too and they now offer them as first choice to their customers. Regarding the installation, excuse me for asking this but why didn't you have the job done at a bigger yard with a covered workshop and with proven experience of this kind of grp work?

 

[BartW]

I was talking to a San Lorenzo guy today and they've had very good experience with the CMC fins too and they now offer them as first choice to their customers.

I visited the San Lorenzo factory in May, with the CMC manager, and we looked at 3 cmc installations, in build in new planing yachts, and one in a refurbished 90ft SD
a interesting and fruitful visit.

why didn't you have the job done at a bigger yard with a covered workshop and with proven experience of this kind of grp work?

well, the CMC guy's had VERY bad experience with a installation done by a bigger and supposedly more reputated yard in that area,
CMC even tried to convince me NOT to do the work in the South of France, as according to their experience, no reliable good yard available.
The Yard we chose appeared to be OK for the job, they do have a workshop both for wood, and also for GRP,
and I like to work with a small company's where you can speak with the boss, and where its all at a small scale,
some of the workers were good craftsman (not all unfortunately) and very nice to deal with
we were able to sleep on the boat during the period of the installation, (on avarage 3 guy's and a cook/cleaning lady during 5 weeks)
which not only for the cost, but mostly for practical considerations was very usefull.
we did some external jobs ourselves; taking off the props for repair, installing the UWL's,...
would all be more complicated in a bigger yard.
and after all I think that the Yard is better then the average in SOF,they have a respectfull heritage, some famous big yachts were there for works
at the moment they just lack some competent coordination- or project- managers.

The reason why I won't go back there is because the next time I need a liftout with a crane with slings, more about that later,
and after that I'll probably sail to Croatia, for at least one season.
and I have a silly financial issue with them.

 

[BartW]

I would consider placing a rubber cover to the internal faces of the U brackets rather than the rails?.....far better on the eye than the tube covering the rail...

thanks Rob and a few others for your sugestions on the rail protection,
I quite like the idea of heat shrink tube on them as NickH sugested, I have them here available in the company,

just one remaining concern,
the pins will make contact / scratch the surface of the rails on one side.
I could place just a small strip of PVC or ....
on one side of the rails,

or heat shrink tube partially over the pins, and bigger upper hole in the U bracket,
but I'm afraid this shrink tube won't stay there, or will be damaged after some time

or anybody a better solution ?

 

[BartW]

Yep, found the clip, you can see the stabs at work here:

Thanks MapisM and Kivi for bringing this, up, thats the video I remembered,
here is another video with the working stabs, made by another friend,

 

[scubaman]

thanks Rob and a few others for your sugestions on the rail protection,
I quite like the idea of heat shrink tube on them as NickH sugested, I have them here available in the company,

just one remaining concern,
the pins will make contact / scratch the surface of the rails on one side.
I could place just a small strip of PVC or ....
on one side of the rails,

or heat shrink tube partially over the pins, and bigger upper hole in the U bracket,
but I'm afraid this shrink tube won't stay there, or will be damaged after some time

or anybody a better solution ?

Rubber might be sticky against the ss rail and give unwanted additional resistance when positioning the tanks so that the brackets/rails/pins align? Could maybe plastic/composite brackets be found?

 

[jfm]

thanks Rob and a few others for your sugestions on the rail protection,
I quite like the idea of heat shrink tube on them as NickH sugested, I have them here available in the company,

just one remaining concern,
the pins will make contact / scratch the surface of the rails on one side.
I could place just a small strip of PVC or ....
on one side of the rails,

or heat shrink tube partially over the pins, and bigger upper hole in the U bracket,
but I'm afraid this shrink tube won't stay there, or will be damaged after some time

or anybody a better solution ?

Nice instalment BartW - good reading. Looks a great job. Sorry to hear you had such trouble with the GRP contractor but I smiled when I read about them laying up too much GRP upside down then it all fell off - that must have been quite a mess!

As regards diving cylinders:

1. If you keep the U brackets and cover them, I'd prefer to hot -dip the U brackets into plastic powder so they are finished like the handles on a pair of pliers. But with #2 or #3 below this isn't necessary

2 Why not create a hole or loop on the goal post for the pin to drop into, to stop the sliding? Like this:

3. Could you dump the U brackets and pins altogether, and have just a carabiner hook on each bottle set towards the top. Then clip this to the loop shown in right side of picture above? (Perhaps the bottles would then be too wobbly?)