The truth about Aluminium sailing boats from a PRO. Hull Material series Pt. 3

Dr Sheddy, 😂

Thank you for making a wider sailing audience aware that cruising boats can be built (and may be better) from other materials than GRP. Seems the French are on the forefront most of the time. Another material has seen a renaissance in French boatbuilding recently is plywood/epoxy. Think RM boats. Maybe a topic for the next vid? Thanks again.

All US coast guard boats and many fishing boats are made of aluminum and the expect a 25 years of service a well maintain aluminum sailboat will surpass your sailing life whit-out any problème.

Aluminium is the best material for boats - with a huge distance to the second.
When it comes to nostalgic aspects taken into account wood comes close.

Before buying an aluminum boat it's probably a good idea to learn tig welding on aluminum. If you have no experience then it might take you a couple months. You'll need the tig setup to make repairs. There are other ways but why bother? Learn to do it right with the proper equipment. You cant make fiberglass repairs without learning how either. Any place you attach stainless steel will corrode.

You fix it pretty much the same way you get rid of deep rust. Use a grinder to get down to good metal then build it back up with TIG. It isn't complicated to a welder, or hard. It does take a little money for the machine and gas bottles and a lot of practice. Might as well get started before you buy the boat. A good TIG welder already has a job, and they work for a lot more than your average mechanic or boat repair guy. You don't want to pay someone every time you need a little repair. If you're planning to use sweat equity this is a great place to start. Just my opinion . . .

So torn between an Alubat and a Neel. Now in PNW, and in these waters, Alubat for sure. I will most likely go south with a Neel. I saw Alubat made few cats but out of my league.

I worked and bought one of the Alum /Foam collered Safe Boat and the prototype ended up as scrap after unprimed alum behind collars corroded horribley where the Ss bolts attached.
The salt formed donuts that grew until the sides cracked.
We later epoxied as much as possible and put
Lanocote on threads for any fasteners.
Urine will destroy a hull , rats or human .
Battery acid too.
One Non- marine battery charger from a neighbor boat will destroy your alum hull if not totally isolated.
An electric start motor sorta makes it hard to achieve…….
Alum was $1 a pound when I bought my $8k hull in 1990.
Now it’s at $3+……
Precious metals go up in value, as long as it is all there.
They use Ultrasound on alum hulls to verify thickness and if compromised.
Welding makes it porous too , why primer in/out is critical.
I saw a Stabicraft get scrapped after it had scuppers plugged and a car battery charger used to keep the bilge running 24/7 as welds leaked so bad. The diver let copper pennies and used zincs roll around it as he worked cleaning bottoms. The stuff scarfed thru the bottom.
“Salt away “is also your friend.

Sailing in a giant anode. Not for me thanks. I'll stick to using aluminium foil in the kitchen.

Delighted you folks are back at sea, kind regards and nice to meet you in Chiapas

This is a great video.

When I was younger my father bought a retired 65' mini-maxi, Boomerang II which was built by Direcktor in Ft. Lauderdale in the late 70's. We sent the boat back to Direcktor in the mid 80's for a complete refit and upgraded the systems and interior to convert it into a luxury cruiser set up for a short handed crew. The boat was Aluminum and built like a brick shithouse! It is currently for sale and sitting on the hard in Portugal. I would love to buy it and refit once again but 65' is a big boat for my limited skills. Aluminum boats are the shit and the best option IMO.

It’s pronounced {A-LUUM-I-NUM} !!!!! 🤷🏼‍♂️🙄🤷🏼‍♂️🙄🤷🏼‍♂️

You two are slightly awkward speakers, BUT the content is SUPERB and presented in an understandable way. Bravo!

Aluminum Oxide protects the Aluminum in the same way that Chromium Oxide protects stainless steel. (Chromium is the key element of stainless steel alloy.) The Oxides make them highly corrosion resistant. The technical term is passivation; the surface becomes passive and not active to corrosion.

ALL boats that have more than one metal in contact with water have galavanic corrosion, including plastic boats that have any two dissimilar alloys in contact with the water. That includes steel, naval bronze, etc., fittings, driveshafts, any throughhulls, etc. Just like any boat with more than two types of metals, Zincs are used on Aluminum boats to control galvanic corrosion. So really this aspect is no different from any other boat whether its hull is wood, steel, plastic composite, etc.

Interesting. What is the (general) price difference between an aluminium and other materials in boats?

its Aluminum not Aulmenuim

I sailed on a French (Joubert et Nivelt) designed Ali 18m yacht in "Meta" construction. Hard chine with plates welded together full length flat, then bent from from bow to stern to form continuous curves with minimal internal bulkheads. 20mm below waterline (yes 20mm), 10mm above with 8mm decks and cabin. With a less is more attitude to paint, above ground wiring, a good amount of anodes, attention to dissimilar metal interfaces (insulation and tefgel) you end up with a very strong, lightish, non corroding floating Faraday cage. Great cruising construction!

I need help! I'm looking for an Amel style vessel (protected mid body helm) but with an aluminum hull. I love the amel's but I want to adventure not only the tropics but the poles as well, and unfortunately amel does not make vessels with aluminum hulls. Can anyone point me in the correct direction? Thank you!

No one has mentioned that Aluminium gets weaker when welded (weld seems)Welding weakens the heat-treated aluminum in the vicinity of the weld, called the heat-affected zone (HAZ), reducing the strength by approximately 40 percent. Any aluminum specifier or designer must account for the weakened state of the welded members. Conversley steel gets stronger at the point of weld.

This lady reminds me of August Ames. I enjoy watching her speak about sailboats, I could probably listen all day 😅

I'd be constantly worried about working in the boat. Maybe designs are different, but my boat has some bilge areas under the engine that are impossible to get a hand into. Dropping a nut, bolt or screw is bad enough without worrying that it's going to galvanically corrode a hole through the hull. And what about cutting stranded copper wire and accidentally having a few little strands end up in the bilge.

I’m from the USA… I think it’s awesome how you pronounce Alyewminneyum

Still don’t understand why no one builds boats out of BRONZE. It doesn’t corrode, welds cleaner than aluminum or steel, and you can plate the surface below waterline with pure copper.

How do Aluminium Bronze and Aluminium when it comes to electrolysis ?

I worked on an old 85 foot wooden fishing boat in Alaska in the 70’s which had a steel stern. While working on the boat one summer the skipper had the wooden bow removed and replaced with an aluminum bow. I was around while the work was being done and got weld burns in the eyes and went to the ER. The following fall we went King crab fishing and the boat performed amazing in heavy seas.

What do you think about making Catamarans out of Titanium, given the nature of Titanium, it's strength, lightness, the fact that it doesn't corrode, etc., etc.: ???
I'd love to hear back from you on this subject. Thank you, AD.

The fact that Aluminium is ductile is one of its major advantages. It’s also environmentally friendly…

If the hull is aluminum, what material is recommended for the masts? What is the mitigation for lightning strikes?

Thought aluminium and salt was a bad mix with aluminium the loser. Reason not allowed to put salt on runways during winter months because it can seriously damage the planes.

Alustar aluminium for the WIN!
I don't mind people being totally out of touch when it comes to my favorite construction method - wasted years trying to explain it all, now I just let them speculate.
Just the fact that it doesn't need paint - co$t and weight - is enough for me.
Thanks everyone for pronouncing it properly too!

It's clear you don't know enough about aluminum to talk about it in the way you (try) to do. It's clear when you mention welding, corrosion/oxidization, galvanic and electrical corrosion etc. You're guessing, or have an idea, but you're in no position to come with advice. If don't know, don' t go into details, you should have kept it more basic than you did.

Wuuhoooo! Really like these videos.
I own a Stabicraft. Best boat I've had and it will last me a lifetime.
I am learning how to work on and weld aluminum to do my own repairs and to delete as many fasteners and accessories of other metals as possible. (Rod holders, grab rails, transducer brackets, etc)
I do have one question. What type or grade of aluminum is used for marine fabrication and what types or grades can be used when repairing or adding custom modifications?
Thank you

You didn't mention impressed current protection. This is essential on any fizz-boat.

I would never choose aluminum for a saltwater environment.

I have three aluminum hulls, one steel and one fiberglass. Hands down aluminum is the best, easiest to care and most durable.

It's Aluminum🤣

Is superior till it fail.

You did not speak about thermal and noise insulation, very weak with aluminium

Aluminium is NOT harder to weld than steel. It's just that not as many people learn to weld it. It's much faster than steel to weld and because it freezes faster you don't end up with molten metal dropping on you in positional welding. And you definitely should never weld through the oxide layer. That man has clearly never heard of sandpaper or a grinder.

A galvanic isolator is a cheap half measure ! The only proper barrier from he shore, for an aluminum boat is an isolation transformer.

they said, al uu min ee um. 🙂

good vid. comments, fwiw... Every metal has its unique properties, so working with it requires knowledge and skill: the hallmarks of a good tradesman. AL is a superior metal for marine applications, for the reasons noted here. But nothing can survive abuse: not even the Titanic. Sailed with a modicum of care, AL will outlast all other metals except stainless. True, AL needs to be insulated to avoid galvanic reaction, but this is no big deal nowadays, more so for power yachts. One pro I have found with unpainted 100% AL boats is they are cooler in hot weather: the metal conducts heat into the ocean, in the fashion of a heat sink. I have found cork decking to be excellent for AL yachts.

This is a very pro aluminium blog. My experience is somewhat different. Aluminium is not a great building material once it ages. The corrosion is a constant battle. You struggle to keep paint on. Give me GRP any day

Great video, was always wondering why you would choose aliminium..

Thank you, well put.
Cheers.

Steel is stronger when welded , aluminum welds are weaker than parent metal .

If you accidentally drop a penny into the bilge you will eventually have a hole in your aluminum hull - electrolysis is a biatch! Aluminum hulls are uncomfortable noisy in choppy seas. Aluminum is highly conductive and it also attracts condensation. Because of this, aluminium boats are notoriously cold during cold seasons. Antifouling is also much more expensive and complicated to apply to aluminium. I wouldn’t touch it with a 10 foot “aluminum” pole.

Been designing a yacht for many years and would choose nothing other than Aluminium. I think people that choose fibreglass are just mad and they all end up as land fill or junk in the ocean. ALuminium is recyclable and dissolves in the ocean over a long period. The hull can also be used as a radiator for engines without introducing sea water in and having more components to clean. Jet drives can be welded directly to it instead of glue and bolts like fibreglass. If you do have a crack or hole, you can also easily screw on a repair sheet of thin aluminium, where as fibreglass screws would just tear out. Any scrap from the large plates can be used in smaller areas. You don't need a massive mold either to construct a boat, my design is 24.8 metres, so I can still build it myself with aluminium. You can modify it by just welding to it, much simpler than fibreglass.

Dr. of what ???

But isn't carbon fibrer just plastic, uno some ⛵ like the Lagoon 40 is a plastic boat?