Are aluminium boats a liability?

[geem]

We had friends around for drinks a couple of nights ago. All nine of us sat in the cockpit chewing the fat. We are all sailors. One couple are proffessional Captain and Hostess off super yachts. He has done it as a career all his life. Talking about boats, we got on to the subject of his professional retirement and buying his own boat. He said it wouldn't be aluminium as he had the best part of his career dealing with "fizzing aluminium". He went onto say that they start fizzing on the day they launch them. He is talking super yachts that are filled with all sorts of systems not normally seen on more moderate sized boats but as boats get more electronic and complicated will this fizzing become the norm on smaller boats?
Another proffessional skipper was telling me about the aluminium super yacht he runs. They have a earth fault detection system that is in a permanent state of alarm. The boat has corrosion problems and is about to go in for more paint work to deal with bubbling paint. It's a regular process. At one point they had 26 faults on the system. They flew engineers over from France who spent 4 days pulling the boat apart.
Another friend has a 1999 Ovni 43. The corrosion on that boat is extensive. Not a complicated boat but the second fizzing Ovni I have had experience of. The last one was a French owner who asked me if I could help him chase an earth fault. His boat was far newer but still had the start of corrosion on the white superstructure paintwork.
The boat I crew on in the summer for a week was a 72ft aluminium racer cruiser. It had patches of not quite matching paint all around the boat. It's ten years old. I asked why and they said corrosion.
So far I haven't met an aluminium boat owner or Captain that doesn't have some sort of corrosion problem on their boat.

 

[vyv_cox]

Many years ago we were berthed in Cork when a famous aluminium boat called War Baby came in and berthed close by. Six overboard anodes were hanging on cables before all the warps were attached!

 

[westernman]

Many years ago we were berthed in Cork when a famous aluminium boat called War Baby came in and berthed close by. Six overboard anodes were hanging on cables before all the warps were attached!

I don't understand the attraction of aluminium.

At the same weight, GRP is much stronger. And is much stronger when carbon fibre reinforced.
GRP is pretty inert. Nothing much can go wrong. And it is easy to repair anywhere in the world.

I am interested to hear if there is any rational argument for building a boat from aluminium.

 

[Wansworth]

On YouTube there is a one off Ali boat being built. distant Shores the owners seem quite happy,at the momment

 

[capnsensible]

Wonder if it's the build quality at fault? There are a lot of aluminium ferries, particularly fast cats around that seem to run for many years without holdups.

I delivered an OVNI, around 40 feet iirc from Horta to a marina in Biscay a few years back. It was mebbe 6 or 7 years old and had spent time in the Caribbean. It was immaculate.

There's clearly a problem though with those super yachts. Must be hard yakka for the crews to keep them going.

 

[Tranona]

I am interested to hear if there is any rational argument for building a boat from aluminium.

Depends on how you define "rational".

Advantages claimed
High strength to weight and thickness
Easy to fabricate
Does not need paint protection
Easy to repair

Disadvantages
As in original post

 

[Concerto]

Yet on the other side, we use aluminium masts and for some deck fittings. There are many yachts built in the 1960's with original masts. So aluminium can be used in a marine environment. It does seem that electrolysis is due to either dissimilar metals or electrical current.

 

[Bilgediver]

A company built Sea Otter aluminium narrow boats some years ago and they still attract premium prices and never heard owners complaining about them fizzing away.

 

[westernman]

Depends on how you define "rational".

Advantages claimed
High strength to weight and thickness
Easy to fabricate
Does not need paint protection
Easy to repair

Disadvantages
As in original post

GRP strength to weight is better (although it is thicker).
GRP does not need paint protection.
GRP is easy to repair.

About the only one which stands up is easy to fabricate for large one offs. (There is C-Flex and some cored methods, but I understand they are not entirely satisfactory).

 

[Roberto]

I have a number of friends with light alloy boats, they are quite common in France, Cigale Allure Ovni Boreal Garcia etc also one-off in thick aluminium (Meta boatyard), tu they are all very happy and no one would change it with another material, though all of them are continuously keeping under strict control everything electrical.
Those in good conditions are as bankers' cheque: put one on sale and it's gone in a matter of days/weeks, they also keep their price a lot better than say grp.
No idea about superyachts

 

[Motor_Sailor]

Have designed and built dozens of aluminium cruising boat in the 40 to 60ft size. None have come back with 'fizzing' problems.

Paint blistering is a separate issue. It took a long while to sort out a satisfactory way of painting aluminium, and is one reason why so many aluminium boats are bare metal.

But done properly, there isn't a better, easier, faster, or more cost effective material for building custom designs.

 

[Tranona]

GRP strength to weight is better (although it is thicker).
GRP does not need paint protection.
GRP is easy to repair.

About the only one which stands up is easy to fabricate for large one offs. (There is C-Flex and some cored methods, but I understand they are not entirely satisfactory).

Deliberately did not compare with GRP - just listed the properties. The comparison is more commonly with steel, particularly for superyachts. Composite structures are common in that market - steel for the hull and aluminium for the superstructure for weight saving.
Metal boats have a following in countries where there is either a shortage of timber (historic) or there is a strong tradition of metal fabrication.

As Roberto says in France aluminium is considered a premium product (also in Holland) but never caught on in the UK, perhaps because apart from firms like Joyce Brothers nobody made boats for the premium market but tried to compete in the mass market where your comparison is valid.

 

[jamie N]

I would think that the 'fizzing' issue would be due to poorly installed or maintained electrics, wouldn't it?
If one isolates the 'wigglies' from the metal, it's going to be fine. I usually compare it to ROV stuff, which as standard is housed in aluminium, and doesn't corrode because it's kept isolated, and can't be operated if there's a ground, as the 'Ground Fault Indicator' will shut down the system.

 

[capnsensible]

Not seen many grp passenger planes.

 

[westernman]

Not seen many grp passenger planes.

The majority of the Boeing 787 and Airbus 350 fuselages are made of GRP (well actually carbon reinforced plastic).

And I have seen quite of few (and been on some as well).
Keep your eyes open next time your are at an airport.

 

[Spirit (of Glenans)]

I don't understand the attraction of aluminium.

At the same weight, GRP is much stronger. And is much stronger when carbon fibre reinforced.
GRP is pretty inert. Nothing much can go wrong. And it is easy to repair anywhere in the world.

I am interested to hear if there is any rational argument for building a boat from aluminium.

They are quite often used for high latitudes sailing, where they can shrug off the ice that would put holes in GRP vessels.

 

[Blueboatman]

Aren’t marinas the challenge for alloy?
All those differing keel materials , steel pilings and wobbly stray electrics in proximity ?

 

[vyv_cox]

The majority of the Boeing 787 and Airbus 350 fuselages are made of GRP (well actually carbon reinforced plastic).

And I have seen quite of few (and been on some as well).
Keep your eyes open next time your are at an airport.

I shared a train ride from Chester to London with a man who built carbon reinforced plastic wings at Airbus Broughton.

 

[Spirit (of Glenans)]

The majority of the Boeing 787 and Airbus 350 fuselages are made of GRP (well actually carbon reinforced plastic).

We usually refer to that as Carbon Fibre.

 

[westernman]

They are quite often used for high latitudes sailing, where they can shrug off the ice that would put holes in GRP vessels.

I know people often choose aluminium for that purpose, but is it actually true that they would not get punctured when the GRP hull would??

Some tests here seem to show otherwise.