Asking fir a friend..

[Tomahawk]

... who is looking at a Grandsoleil 47. 2002 vintage.
There is indication of heavy grounding. A gap between the aft end of the keel and the hull.

Does anyone know how the keel is made and what the hull structure looks like?

 

[Concerto]

I would suggest your friend should contact the nearest agent for a detailed answer.
Dealer List - Grand Soleil

 

[Neeves]

I wonder why your friend, and others have the same introduction (asking for a friend), don't simply join the forum. Its not onerous, its free and they may find they can contribute to threads with applicable information.

There is nothing wrong with asking for a friend - I just think it would be advantageous to enlarge our pool of knowledge.

But - takes all sorts - would not do if we were all the same.

Jonathan

 

[Bajansailor]

Is that 'gap' the only indication of a heavy grounding, or are there others?
Can you ask him for some photos that you can post, including photos inside the hull showing the bilges and keel bolts if possible?

 

[Spirit (of Glenans)]

I wonder why your friend, and others have the same introduction (asking for a friend), don't simply join the forum. Its not onerous, its free and they may find they can contribute to threads with applicable information.

There is nothing wrong with asking for a friend - I just think it would be advantageous to enlarge our pool of knowledge.

But - takes all sorts - would not do if we were all the same.

Jonathan

Not wishing to impugn the OP, but the phrase "Asking for a friend" is the shield that people sometimes give themselves when they are asking about something on their own behalf but are too embarrassed to be seen doing so.

 

[Neeves]

One should never be embarrassed - we all make silly mistakes - and running aground is hardly unusual. But maybe multi hull owners do it more frequently.....?

Our keels are sacrificial - in theory we can rip them off and stay seaworthy, though leeway might be an issue. I've never tried it and losing a keel would be expensive.

Jonathan

 

[Daydream believer]

I saw a 45 ft G S on the hard in Ijmuiden back in 2005. The keel was surrounded in tarps. I looked under & the lead bulb had been ripped from the cast iron fin & there was a clear 50mm gap all the way along its length. It was still attached, but the bolts were all splayed & partly pulled from the lead.
The lead had a large chunk out of it so it had clearly had a massive wack to cause such damage
So the answer to the OP's question is -probably cast iron with a lead bulb

 

[Concerto]

I saw a 45 ft G S on the hard in Ijmuiden back in 2005. The keel was surrounded in tarps. I looked under & the lead bulb had been ripped from the cast iron fin & there was a clear 50mm gap all the way along its length. It was still attached, but the bolts were all splayed & partly pulled from the lead.
The lead had a large chunk out of it so it had clearly had a massive wack to cause such damage

Looking at the hull profile of the Grandsoleil 47 with a very deep thin fin with a torpedo bulb, the loadings exerted if grounded at speed must be massive due to the leverage.

 

[Wansworth]

One should never be embarrassed - we all make silly mistakes - and running aground is hardly unusual. But maybe multi hull owners do it more frequently.....?

Our keels are sacrificial - in theory we can rip them off and stay seaworthy, though leeway might be an issue. I've never tried it and losing a keel would be expensive.

Jonathan

The op sails a triple hulled boat…….so maybe has a friend?

 

[Daydream believer]

Looking at the hull profile of the Grandsoleil 47 with a very deep thin fin with a torpedo bulb, the loadings exerted if grounded at speed must be massive due to the leverage.

Actually, the hull to keel joint looked OK on the outside. But there is no saying what the inside looked like. I cannot imagine that there was no damage in the flexing. But if not, then that would be a massive plus for the designers & builders of GS

 

[Neeves]

The op sails a triple hulled boat…….so maybe has a friend?

I'm sure he has many friends, with a triple hulled yacht he is a man of taste and discretion. Hopefully he only has 2 of the hulls in the water at any one time

An individual wishing to buy a Grandsoleil 47. 2002 will have a bucket, if not bath, full of expertise and experiences - which can only add positively, to the cornucopia of knowledge embedded here - it would be nice if the knowledge were available to members - not a distant friend.

Its better as a 2 way street rather than a 'no through road' - or I hope so.


I'm no expert on groundings of keeled yachts - but if you hit something hard and unforgiving does not the keel move 'backwards' sort of and a gap would normally develop at the leading edge of the keel - not the aft portion.

Lessons on groundings needed

Jonathan

 

[Wansworth]

I'm sure he has many friends, with a triple hulled yacht he is a man of taste and discretion. Hopefully he only has 2 of the hulls in the water at any one time

An individual wishing to buy a Grandsoleil 47. 2002 will have a bucket, if not bath, full of expertise and experiences - which can only add positively, to the cornucopia of knowledge embedded here - it would be nice if the knowledge were available to members - not a distant friend.

Its better as a 2 way street rather than a 'no through road' - or I hope so.


I'm no expert on groundings of keeled yachts - but if you hit something hard and unforgiving does not the keel move 'backwards' sort of and a gap would normally develop at the leading edge of the keel - not the aft portion.

Lessons on groundings needed

Jonathan

Agree ,especially problems with grounding with fin keels. a vexing quandary whenlookingtobuy second hand yachtsí

 

[Neeves]

My knowledge on performance fin keels, with lead bulbs, is that they are often machined from a piece of high tensile steel. I believe Wild Oats keel was based on Bis 80 (the steel made famous by the Smiths of Rocna fame). I queried the idea of machining HT steel, for both keel and shanks - but apparently its not uncommon (and might be how the shank of the Vulcan anchor, or son of Rocna, is made)

Not quite a GS - this one cants.



You see its easy to turn an innocuous thread into one on anchors . - with sincere apologies to Tomahawk and his friend.

Jonathan

 

[mjcoon]

My knowledge on performance fin keels, with lead bulbs, is that they are often machined from a piece of high tensile steel. I believe Wild Oats keel was based on Bis 80 (the steel made famous by the Smiths of Rocna fame). I queried the idea of machining HT steel, for both keel and shanks - but apparently its not uncommon (and might be how the shank of the Vulcan anchor, or son of Rocna, is made)

Not quite a GS - this one cants.

View attachment 144217

You see its easy to turn an innocuous thread into one on anchors . - with sincere apologies to Tomahawk and his friend.

Jonathan

I'm sure that should have a security chain to prevent total loss, but no doubt that would compromise performance...

 

[mjcoon]

To combine ideas above, I claim invention of a fin keel with a ball-joint mounting to the hull. Moved fore-and-aft it changes draft for creek-crawling and gives resilience to grounding at speed. For speed merchants it can be canted laterally for stiffness...

 

[Spirit (of Glenans)]

I'm sure that should have a security chain to prevent total loss, but no doubt that would compromise performance...

That's a great idea. Would save lives.

 

[Tranona]

None of this helps Tomahawks friend.

No such thing as Grand Soleil 47 from that year. Almost certainly a 46.3, one of their popular models from around 1998-2005. Looks like a pimped up Bavaria, not surprising as same designer as the concurrent Bavaria 47 - J&J Design. Lead 2.2m keel with a trailing bulb, again just like the Bavaria. Similar moulded and bonded grid structure inside.

So, usual observation. Depression in the hull aft of keel and keel separation from hull is sign of grounding or dropping from slings. Internal signs usually damage to the grid and woodwork forward of the companionway steps up to the galley/saloon bulkhead. See details of boat here (not the one in question, hopefully) devalk.nl/en/yachtbrokerage/203807/GRAND-SOLEIL-46.3.html

 

[RunAgroundHard]

So, usual observation. Depression in the hull aft of keel and keel separation from hull is sign of grounding

Previous advice on this forum was that a “usual observation” was at the opposite end, when the hull rotated down as the keel struck with damage inside at the front of keel area. This was in keeping with a gap at the aft end of the keel. My own experience is of the front flange of the keel base cracking and forward rib at front of keel being damaged. Hull was pre grid design. I didn’t comment as I was sure the OP boat was a grid design and I didn’t know how that would present. I have been associated with 3 hard groundings, and all experienced the same damage, internal GRP damage at front of keel.

 

[Tranona]

Read the complete sentence. Yes a grounding when the keel hits something at a point higher than the base will have damage at the front, but sliding out of slings often affects just the rear. More than one example of such damage reported on the Bavaria forum. From memory the keel on the 47 design only has one bolt at the rear end and landing on the trailing edge of the bulb will likely cause damage just at the rear.

 

[Tomahawk]

I wonder why your friend, and others have the same introduction (asking for a friend), don't simply join the forum. Its not onerous, its free and they may find they can contribute to threads with applicable information.

There is nothing wrong with asking for a friend - I just think it would be advantageous to enlarge our pool of knowledge.

But - takes all sorts - would not do if we were all the same.

Jonathan

He is new to big boats after a lifetime of small boats. But you make a valid point I will introduce him to these venerable pages..