Aluminum hulls

[SailDesign]

Gonzo,
Not in my experience.
YMMV

Steve

[Polarity]

unlike aluminum which splits and peels like..... like...... like an tin can ;-)

LOL

I'm with you on either Kevlar or Aluminium, but I dont trust FG which is what we were originally talking about.

Would I rather hit something in a 50ft FG Benjenbav or my Aluminium (with crash box!) hull? To me the ans seems obvious, but I dont know that much about what goes into the composite mix at the pointy end of a modern FG production boat. I remember reading about the use of Kevlar or twaron for crash protection in some yachts...

It would be interesting to see the numbers - but since people are still discussing if steel or Alu is better in an impact I dont hold out much hope...

Paul

[duluthboats]

This article relates to the topic, http://www.reinforcedplastics.com/WZ...t/000011/show/
and the site has a lot of good info for us all.

Gary

My experience on fishing boats in alaska has tought me about that fiberglass, kevlar or whatever. I've seen what happens to glass when hits rock, and it was never pretty. With our aluminum boat, we never had any problems with anything.

[AlexMorozov]

Originally Posted by artdeluxe

Hello there,
I have a question for you. I am doing research on 32-36 boat designs. Fiberglass is a material of choice. But I would like to try to special order hull made of aluminum. The reason – I would like to go off shore a lot, so I would like boat to be impact resistant and easy to repair. Also weight is an issue. So all your thoughts on this are welcome. Reason why I am asking for an advice is that I do not see too many 32-36 boats made of aluminum. Price in this case is not really an issue. And I am not talking about ugly hull. I found a ship yard where they can build a hull of almost any shape. I kind of like this idea, so your con’s for using aluminum for a boats of this size would be very welcome.
Thank you,
Victor

Hi,
the aluminum hull shape is not issue today, we build fully rounded version of Fisher37 type, seems aluminum motorsaler is good choice for nowdays as cruising boat.
http://www.morozov-yachts.com/catalog.php?view=16

Alex

[gonzo]

Automotive designers have been making a huge variety of metal shapes in mass produces vehicles for over a century. Most boat manufacturers are still not using the existing technology.

[AlexMorozov]

hi, but existing automotive technology is fine for production good. The proper boat (cruising) to be mainly custom, so rather simple tools cld be used for boatbuilding. It is more matter of expirience of builder and time schedule, then technology. I think that it is reason that no too much of aluminum production boats on the market.alex

[Bob Mott]

did anyone know that the 1895 yacht defender that won the America's Cup was a steel frames with riveted alloy hull. You dont have to weld alloy to repair a patch you can rivet a patch over the damage with some self curing adhesive behind.

Alloy is lighter than GRP in boats over 11 metres. At around 16 metres a GRP hull will weight in at around 12 ton and alloy at 7.5 ton. There is a big misconception with GRP weight against alloy. The newer alloys such as Alcan/Perchiney Sealium is stronger than the older 5083 and more corrosion resistant. They are working on better welding wire to reduce the HAZ area Heat Effected Zone and have already developed friction pressure welding equipement where not gas or electricity is used for the weld - reducing the HAZ even more. Plenty of advances in alloy. I will be using Sealium products from France to build a number of 15.4 metre performance sailing cats in Thailand. New design - quick - naval arcitect designed. Should start by September when the alloy arrives. It is going to be a great project - looking forward to it

[Bob Mott]

Is size an issue?? If not look at doing a alloy cat. What is the intended purpose of the boat?? I am into my second alloy cat and will be beginning to build a number of new design cats in Thailand.

For me alloy is the material of choice.

Bob

[AlexMorozov]

The issue is not a size, but man/hours to build such boat. On smaller boats of aluminum, less volume then on similar grp due to frames and stringers width. We built few boats in range 6.5 - 9 meters, they were very solid boats for all life, but very expensive.

[Bob Mott]

Hello Alex,

In Australia approx 3000 Hrs hull and deck, fabricated hatches, rudders, daggerboards, steering. In Thailand around 5,000 Hrs. Same boat 15.4 metres.

In Australia the hourly rate is around 50AUS$. Thailand 10AUS$ equivelent

50K against 150,000K same cat. Material costs the same or close.

End product fitted out around 500,000AUS$

Buy that in Europe/USA/Australia = closer to 700,000AUS$.

Quality the same - Lloyds certified welders.

Bob

[Bob Mott]

Also production versions in GRP or other forget it more like 800,000US$.

[AlexMorozov]

Hi Bob,
Now I working on new project of expedition motorsailer 64ft, surely of aluminum. Hull weight about 9 tons. I looking to Sweden/Denmark and lastly to Turkey. But the question not only welding the hull, but finishing the completed yacht, not fishing trawler but yacht. I build some big aluminum yacht in Russia, but partly works are good, but all together not give the proper "yachts" quality. I know the Christian Andersen yachts, good proper boats, probably Thailand has good yards to build the really yacht. If you give some links to have a look at that products, it will be very kind of you. Your figures looks good.

[Vega]

Originally Posted by AlexMorozov

The issue is not a size, but man/hours to build such boat. On smaller boats of aluminum, less volume then on similar grp due to frames and stringers width. We built few boats in range 6.5 - 9 meters, they were very solid boats for all life, but very expensive.

Yes that's why doesn't make sense to build a 34ft aluminium boat.

Take a look. They are strong, fast and I like them:

http://www.atlanticyachts.nl/