When did metals lose the high-tech edge?

A gentle reminder to those who have a lingering fondness for STEEL boats
like their fathers made - and are feeling a bit put out by these new fangled
' com - po- seets......'

( I'm still in upset about the fading of wood..... myself. ")

If you take the term 'composite' literally - how it is used in engineering terms.
- That is: having two, or more - different materials joined together, to synergisticaly work better in combination - than apart.

Then consider: - most steel vessels are really composite boats - as well.
When the ferro material is covered with EPOXY - at least two benifits occur.

1. Rust is significantly reduced. ( Significantly effecting life expectancy)
2. Electrical concerns also go down.

Sounds synergistic to me.........

It is interesting.... that, what commercial ships and the latest gee - whiz
America's Cup boats have most in common is.....epoxy !

 

Figgy has the answer, fashion and perception are much more important than practical considerations in material choice. Look at a material that is completely out of favor, cement, last choice, why? Yes it's difficult to get right but it's not a bad material for certain uses. But no one uses it because the market says it's worthless.

A offshoot of this is the trained skilled manpower to build in a given material. We build lots of aluminum boats in the PNW because 46 years ago Sam Matsumoto started working on getting them accepted in the marketplace. Almost every welder in the PNW can trace his training back to that one shop. They don't build aluminum yachts in China because they don't have the skilled aluminum boatbuilders available right now, but they soon will.

The original question was when and why? When was apparently the mid/late 80's when it became possible to create large, reliable, lightweight structures in composites. The why is it was the new, cool, techy thing, and every serious racer had to have it. Still do. Back then it was epoxy and S glass on foam, now it's carbon and honeycomb.

Though we may be seeing things go the other way as we speak. I just saw pictures of a recently launched super tri (Groupama?) with metal riveted to her composite beams!

I certainly don't see any material has "faded". I know I can build a stiff, light, reliable and competitive wooden raceboat, multihulls too, but the market is not interested. Personally, I'll be looking for the carbon on display the next time I get on a big bird.

All the best, Tad

 

He's Global Challenge record from 2004 was also set in an aluminum boat.

http://www.vdh.fr/gb/le_bateau/caracteristique.htm

 

Thanks Milan, I was not aware that that one was aluminium as well...

I think the real reason racing projects go for composites is that they allow you to sculpture your strength in a very detailed manner, sort of following your FE stress graph and build everywhere just the amount of strength and for just what you need, traction, sheer, flexibility ... from a combination of the best suited fibers, cores etc always optimizing for weight.

Obviously this is VERY expensive in design and research, no easy fall back on scantling rules, but if the financing is there, superior results can be archieved.

Optimizing sheet metal construction is limited to using a clever combination of sheets, curvature and structure. ( Maybe I should grind off a few millimeters of sheet thickness on my steel hulls in areas where I do not need it ?? )

In aeronatics they do the same thing, gliders have been composite for ages, because performance counts, and passenger planes will switch as soon as fuel and maintenance costs will get favorable.

Because Groupama was mentioned: from what I understand they also replaced fittings with "baked in" integrated composite parts, saving on fastenings and weight again all in controlling strength in non-assembled structures .

 

Carbon fiber can be build lighter for the same weight and is cheaper since it last longer, but for something that is going to race just a few hours a few times a mounth that is really not the problem.
It will be replaced after 1 or two seasons and will have less than 24 hours off racing on it and maybe 48 hours off testing.
Now I'm thinking off the formula offshore.

The Taiwanese coustgard is now replacing there fiberglass hulls and carbon fiber hull's produced by us with aluminium hull's produced by us and steel hull's produced by a competitor. The reason is life span.

 

Interesting points all.

I wonder what the makers of Alustar and Selium would say?

That would make an interesting building competition – between two fully-established professional boat yards – a complex monohull shape – one built in ally and the other in carbon epoxy etc. and see what the delivery times are like (also what times for the fully-rigged boat – if the hull-materials have bearing on the boat setup and rigging times).

 

If you want custom made it wont take long to cut plates for a aluminium hull and weld it all together, but for the composite they would nead to make the mold first. If your going for a standard the composite hull will be out off the mold befour the aluminium is welded together.

 

I have just asked both Aluminium makers Corus (Alustar) and Alcan Marine (Selium) for their thoughts. I look forward to their responses.

The Van de Heede Global Challenge (see above) was sponsored by Alcan Marine and it won I believe.

 

I agree. Perhaps very hard windward Global Challenge type of races is the only kind where aluminum is still competitive.

Just leave these areas unpainted for a while and wait… No boring grinding.

Well, I might be wrong but I think that general aviation builders are nowhere near that switch and that aluminum will stay main building material for a long time. Just consider main advantages of alu over composites:
Low cost and widespread availability;
Durability and resistance to sun and moisture
Easy to work with: requires simple tools and processes, and does not require a temperature-controlled or dust-free environment, as with composites.
Environmentally friendly: no health hazards to worry about when working with sheet metal; recyclable;
Easy to inspect: construction or materials flaws are easily detected, as are defective parts and damage.
Simple to repair: rivets and fasteners can be easily removed to replace damaged parts or sections, and individual parts can be replaced without having to replace or rework an entire airframe section.
superior crashworthiness ,as an impact’s energy is absorbed by progressively collapsing the metal structure, as opposed to splintering or shattering upon impact.
Inherent lightning protection that a metal airframe offers.

Milan

 

When did metals..........

This is another one of those potentialy,endless debates.

However, it's appreciated, when people with informed experience
contribute. As is the case here.

The WHEN - I leave to better historians than I.
As to the WHY.........

Yes, Sam Matsumoto ( Rest his soul ) is the Grandfather of alum.
boat building here a'bouts.

It should also be noted, for those not living near by, that what he
built were closer to ships than boats.
Where 1/4 plate would have been his MINIMUM wall thickness.

Which serves to illustrate my point that - the choice of hull material
- STARTS: with the minimum, PRACTICAL wall thickness.

Also: he worked on local government contracts. Which supports the
possibility - that having some of the largest Hydro Electric potential
in the world and a large alum. smelter - needing copious amounts
of electricity and market for the product thereof....

Is it not possible, that Sam's vessels,excellent though they were, were not part of an elaborate, gov. marketing program ?

The point remains: the local use and COST of a given material - is not
always a function of a pure engineering requirement - or of TRUE
market forces.

- Please dont take me to task; over wood.
I agree with you completely.
In fact - I very often, COMBINE - Yellow and Red cedar with epoxy and
carbon fiber in my composite vessels.

- Re: Ferro Cement.
I'm more than happy to show anybody - ferro cement creations done
by yours truly. Still in use, after a quarter of a century.
- However, I'm not about to rush out and start building a fast, small
multi - hull sailboat out of the stuff. Anytime soon.

Once again, going back to wall thickness - which is, I'm sure everybody
will accept - very much integral to Overall Length. One of the more
famous of my ferro wonders is around 80 ft in length.
With a wall thickness, well over 1/2 an inch.

To: Milan

The Global Callange refered to: doesn't discount my concern's re: BONDO.
Clearly from the photos, the vessel is not built to any strange rule.
The lines are clean and simple - with a min. of chines and changes
in curvature.
The lack of paint also indicates that no " fudging " was done - to FAIR
the hull. Proberly not an oz. of bondo on her !
An honest boat that deserves her sucesses.

However, as we all know, in the history of America's Cup boats - with
the armies of Sea - Going lawyers involved - vessels were designed with
shapes not always easy to resolve in metal.

To: MarkC and Stian M

I accept the challange.

Below a certain, reasonable W.L. Length I'm more than ready to take on
ANY Alum. yard, on the planet.
One with a well established history - or a brand new yard.
Enthusiastic young " go - getters " or experienced wise, old shipwrights.

Of course - I have an unfair advantage. Or two.

( A.)
Localy we have been witness to one of the biggest ship building
disasters in Marine history.
- The so - called: Fast Ferry project.
Involving - a BILLION $, or so.
Involving - Welded ALUMINIUM ships.
( The WHY of this mess- I'm only too aware of and so I know only
to well, the difficulties INHERENT in alum. fabrication.)
( B.)
We can build an extremly strong, long lasting,
carbon fiber composite vessel - very FAST.
Including the time req. for DESIGN and ENGINEERING.
Build it faster and FAIRER than any tin boat.
Because, we dont need to make a female mold.
It's called a Strong - Back (or male mold )
- Not exactly a new concept.
It helps if the designer comes up with developed curves, or
similer procedures - that are " self fairing ".
( C.)
If even more speed in the constuction process is required,
we includ the cross members of the Strong - Back:
- INTO the vessel it's self. Said members, becoming the water tight
bulkheads of the final boat stucture.
Therefore, no time is wasted taking the boat out of a mold.
- Or ripping out the Strong - Back.

So to repeat: I accept the challange.

Also we add: that we are ready to start with a blank
piece of paper AND includ: both the time required to
do the design and engineering. To established
international standards.

- Just give us a fair and reasonable design brief, plus a retainer
- and we will get right to it.

 

I don't know is that bondo really unavoidable. I'm seeing quite a few of unpainted sailing boats around and they look perfectly fair to me. (These are cruising boats, so plating is probably thicker then it would be for racing boats of similar size).

 

But an important debate nevertheless - why not argue over sensible points - perhaps we have missed something.

I draw your attention to an article taken from www.boatdesign.net own website:

But what if we want a boat that doesn't have 'developable shapes' or 'developlable curves' for 'self fairing' work?

Developable shapes or not - one can call the metal supplier and have your sheet thickness ordered and CNC cut in the shapes you want and delivered to your door (OK - CNC only available for the last 10 years or so?) and Alustar and Sealium aluminium formations as well which have raised strength allowing thinner sheets (Corten steel too). There are old stand-bys: press-brakes, english-wheels - and some very funky new MIG welders (also in the last 10 years - FAST!) or use rivets (now there is an argument!). The grinding, sanding, polishing industry also hasn't been asleep.

A filler for fairing is probably not needed.

In addition the Alustar and Sealium aluminium formations address that minium practical hull thickness issue to some degree.

So are staff -

Poaching anyone? I mean that argument applies to all industry.

In addition - there have been building failures, accidents, mistakes etc with all building materials. We could all provide examples.

I am beginning to believe that the WHEN could relate to the WHY. As Tad mentioned (above) the epoxy, glass, carbon, honeycomb seemed to be the progressive material at that time. Was that marketing, a more stable price, more suppliers? Perhaps carbon etc. pushed the metal-makers to experiment with formulations (Managanese Aluminium for higher strength, especially with welds - Alustar, Sealium). Is this just part of a cycle?

 

There is a general aviation move to composite construction (Cirrus, an all-composite design, was the largest selling GA company last year, and an all-composite Lancair has also been certificated, Boeing's 787 will be largely composite, and the Beechcraft Premier 1 business jet is all composite). Just like our situation, there are pros and cons with both. Basically, it is understood that for the same structure, an Aluminium GA aircraft will weigh less than the same plane in composite.

However, because aluminium aircraft are rivited (in general, the new light Jet, the Eclipse 500, being one of a couple of exceptions), the composite aircraft (which are generally seemless), have less drag and therefore have generally superior performance to aluminium (higher cruise speeds for the same power). Aluminium is preferred where aircraft are to be produced in great numbers, as they are quicker to build, which is why a lot of homebuilt aircraft, which sell in far less numbers, are composite and most production aircraft are aluminium. There are also significant issues associated with the FAA certification of aircraft build out of "unconventional" materials, and most companies would rather steer away from this bureaucratic process.

Dave

 

Focusing - METALS losing their edge

Re: POACHING.
- The yacht builder quoted, did not invent " developable curves ".

It's common practice with boat builders. Wether they know it or not.
It's a very practical way to get a " curve " into a simple plywood skiff.

A multi - hull, design consortium - way back when - put a little more
science into it. Coming up with a generic male mold that you can pull
off, both - cat or tri hulls.

The classic Olym. cat - the Toranordo (?) - uses, what is referred to as
- " tortured " construction. Where the poor man's, composite
- plywood - is forced almost to breaking point, to " develope " a curve
over a male mold.

Re: FAIRING

I have seen MASTER boat builders in alum. - have plate purposely
cut over - size. Then as, said plate deforms - INEVITABLY
- as it is welded, it takes on the desired shape !

So, yes, SOME builders - use less bondo than others.

Commercial builders dont bother with bondo - for sure.
Next time you are at the dock - take a look down the side of
any ship. Each time a transverse member meets the hull there's
a change in fairness.

- I have also seen composite builders fire two " fairing " crews in a row.
Because they could not fair the boat they were trying to make.
- Because: Fairing requires Art and Skill. Or sophisticated machinery.

By the way: the convenience of having all your metal plate pre - cut,
does not give you any clear advantage over a composite builder.
( The presumption, with much that has been stated, is that composite
means: Molds and glassfiber.)

Note: Composite builders, have the freedom, to make use of panel fabrication - in just the same way as an alum. builder might.

Point is: A good Composite designer and/or Builder KNOWS how to
deal with fairing - without excessive costs or time delays.

It comes down to this:

The original question referred to - " Metals losing the high tech. edge."

My going on about wall thickness - was to indicate one aspect that
effects the whole.

Most high tech. stuff discussed - referrs to RACE boats - often not
more than 60 ft. in length.
The Round the World guys staying close 100 ft.

Commercial ships are significantly bigger.
With them steel is first - with alum. next - when weight becomes
a factor.
Decisions in these vessels lean more to the practical, than the
evangelical.

So, perhaps we need to follow their lead and not feel that we have
to be evangelists, for one design process or material over another.

Simply put: as metal ships become smaller - and start to become
referred to as - BOATS, metal becomes less PRACTICAL.

A small metal boat will turn out, generaly, suprisingly HEAVY.
( Even in alum.)
And heavy, simply: doesn't win races.

 

unfortunate but true BUT only true with small boats 80 foot 100 foot and under
i had a yarn to ISABELLA AUTISSIER whom I regard as perhaps the worlds best single hander, just before she capsized for 2nd time afater leaving Auckland, , this was years ago, and, she said competitive alloy boats died 5 years previous to that race
As an alloy builder of many years, I knew this, but at time was looking for a competitive yacht
NOW if you wanna build a fast 150 footer? see me ) cheers Stu