Not another one!!

Yeez whoosh, what is you problem with everyone that differs from you:?:

As a matter of fact I did my first boat professionally, a v/d Stadt 34 with Corten on the insistence of the client. That was against my advise to him and the fact that the plans called for 4mm and the thinnest Corten in my country is 4.5mm - and that added a few good kilos to that hull.

Further more, I spent a lot of time in the mining industry, remember I am a fully qualified boilermaker, before moving over to become as a pro boatbuilder.
The goldmining industry in SA where I worked used Corten exclusively for all the underground equipment such as hopper chutes, hoppers (rolling stock), skips etc. because they were sold on the idea it is harder and resists rust. Ever been in a deep goldmine to see how wet is really is down there?
Best part, many times we had urgent repairs to the equipment, and no Corten in stock, and we use mildsteel to get production back on line, and in fact, no difference in rust resistance could be seen between the two steels.
Rocklast steel, and Bennox outclass Corten under extreme and abusive conditions....

Perhaps my 17 years working with Corten is not enough to raise my views about it in whoosh's view....

 

Whoosh, what have I done to you that you feel the need to antagonise me? You seem to have a problem with anyone who has an opinion different from yours.

Yes, I have seen Ganley designs. No, I have not sailed on one. I have known owners and every one of them was happy with his boat. Most of the owners whom I met were passing through Cape Town on circum-navigations. Those who were unhappy with their boats would have stayed closer to home.

 

Does anybody else feel that Ali would be a better option than steel?

I have no problem being able to work Ali although i will have to brush up on my MIG/MAGS skills as i have mostly TIG/TAGS welded Ali.

I am probably from the same school as yourself wynand in that i started as a boilermaker and have been down mines and worked with similar materials. This is why i wasn't convinced with Corten. There are similar metals i have dealt with in oil industry as well which didn't take too well to being formed and became expensive because of this. Also as you say you are restricted by what the mill produces and some of it comes to NZ in odd ball sizes. Most of the local steel suppliers for the quantity needed will need to get it in from Singapore or the likes.

I have noticed a lot of designs are now in Ali and am wondering if my initial thought were far off track. There are far more Ali designs available and a couple of designers have questioned why i would be using steel if i can work in either material. I seems most steel designs can be made from either material.

At least i know what i want it to look like now.

 

Though Corten was not the "miracle metal" that it was supposed to be, it is only one in a spectrum of HSLAs available. Having said this, I don't believe that the higher dollar investment in building with any HSLA would pay for itself, over the costs associated with building in mild steel, whether for the professional or amateur builder.

Aluminum - LOL, that age-old argument that you find on every boat building and/or design forum! I've seen some nice boats built with Al. From a steelworker's perspective, Al is expensive, as is the weld equipment & a pain in the butt to work with. I've come up with a few concepts for repairing steel marine vessels that have been damaged at sea, but aluminum? Based on my own experiences, I'd want to x-ray all structural welds on an Al boat that I was buying or building. Still, there are some beautiful examples out there for the well-heeled owner.

$22,000 sounds like a ridiculous price for plans for a boat, unless you are a government, then its cheap. However, you are buying a name; more important for the professional builder than the amateur.

Bruce Roberts - I've seen a few very nice boats built from his designs & have seen many & worked on a couple that were garbage. I believe that the chief problem is that more of his boat designs are bought by first-time builders than that of other designers. Yeah, the spray class is overweight & has poor seakeeping abilities, yet, so was the boat that they are fashioned after.

my 2c
Mike

 

For amateurs I would always recommend steel ahead of aluminium. If they choose aluminium then they had better first invest a lot of time in training themselves in the proper preparation for and welding of aluminium. If not then they are at serious risk of a calamity at sea from failing welds.

For a professional, with the ability to work and weld aluminium properly, I have no hesitation in recommending aluminium ahead of steel. The boat must, of course, be built with compatible marine alloys. Aside from the preparation and welding issues, it is easier to work with than steel. The lighter material is less demanding of lifting equipment and can be cut with woodworking tools. It is much quieter to work as well.

Yes, the material and equipment cost more. Overall, it will add about 10% to the cost of the boat but resale value will increase by considerably more than 10%. If you leave the skin unpainted above the bootstripe then much of the fairing and painting cost will be saved to partially offset the increased material cost.

Yes, steel can have a welded repair done in most out of the way places around the world, not so with aluminium. That does not mean that aluminium cannot be repaired in an emergency. The same way that a plywood boat can be very quickly repaired with a few pieces of plywood, some screws and underwater grade epoxy, so can an aluminium boat be repaired with the same materials; or replace the plywood with thin aluminium plate.

An added benefit is improved performance. That means faster passage times and improved ability to sail away from dangers at sea, such as extreme weather conditions.

For myself, I would take aluminium ahead of steel.

 

to DD, i HAVE SENT YOU A PM, AND BELieVE ME i AM NOT TRYING WIND YOU UP SORRY, IF YOU SCROLL UP THE thread you will see I recommend you ahead of the other names that came up

to Wynand please dont read more into the posts than you do

i get rather tired of people making FACTS fom the fiction in their minds

On a recent trip to Netherlands, I saw a high speed tender built from Corten, they had to do it that way because mild steel was not strong enough for this service without going for really heavy plate.
i once was asked to roll some transom cnrs for a superyacht, they were only 500 deep as it was for a platform, , my 5 inch rolls would not budge the 6pl, so I had to form those bits in the wheels. the big downside of the metal is that it pulls like mad, bit same as ss that way

I guess I get peeved of people who guess, I can tell they actually are quoting heresay, not from experience
unfortunately I can not tell you in here abt a design name that came up suffice to say there was some legal stuff involved(not me) but was asked to advise
it could well be that you are supersensitive?, but until I talk to you, then please there is no need to interfere is there?
Reply to DD,
I found it took five years to get a welder really up to it, even if he had an ASME 9 or soem other high fallutin ticket, welding is a thankless task, after a day sticking in one whole roll, I would be quite ill

I posted thsi in its own thread a week ago, not one reply, ddi it shock some?

when I was very young there was a man who boarded with us- My dad and I were building a BARTENDER, from ply with massive chines, stem and stern members
Anyways this bloke said you "should be able to belt a hull with a 20lb sledge and it should be able to stay intact"
Years later I read of a boat sunk by orca, she was oaken planked 1 1/4 inch with close spaced oaken frames and floors, she sank in seconds, the book ,Survive The Savage Sea
later again I became a long time builder of metal yachts , oNce I stood on a plank and belted as hard as I could with that hammer a reluctant seam on a tight U forefoot, I was thrown off the plank, only gradually did I move the 5/16 , 8mm plate
I read abt the fleet of steel 65 footers going round ( the wrong way) and how every one of then tinn canned the forefoot area, either too lightly plated, soft plate of too wide frame spacing or all 3
To me having been at sea in tugs, and also sailed such stormy seas as the Tasman, it seems that the sledge hammer test is a good and sensible one
I saw a bloke launch a cat here, he told me he was going to Fiji, 3/8 ply, a mere flick of a sleeping mammal tail would sink that boat, but I just said to him, nice job
YET how many boats could take the hammer test?
When I,m surfing down a wave at night I like to think I,m safe
Greens perhaps the most successful of carbon fibre builders ever, where made to build a section of hull that would be used in such testing for the new boat Shamon, an iron weight was swung at the piece, I am not sure of the weight but it was pointy!!
Greens have had great success with carbon, their round world racers such as Innovation,kaverner surviving totally intact
what do you reckon, can your new boat comply?
And here I think I mean for offshore capable craft

 

Looks like you are a one track minded individual - always your way Making facts from fiction:?: If you open your eyes and mind you will see that the quotes I made from your miracle plate are taken from the attached specification sheets and that is a fact.

I think you are the fictitious one around here, sitting behind a computer and trying to discredit people for whatever reason you have that mystifies my mind.

Then again your are also clairvoyant:?: I was raised on the assumption that until proven guilty or has to assume innocence.
Until you can prove me or any other person wrong, keep your mouth shut and be constructive in your comments.

I am a boilermaker for the last 31 years and any b/m for that length of time would have "bumped" into Corten, and unfortunately, I had spent 17 years in the mining industry that mostly work with that crap.
Welder4956 echo's my sentiments on this and funny enough, he has the same qualifications and background as I...

Some wild statement, but since you thrown a stone in the bush.... Unfortunately, when you build boats, or is in business in any other discipline, you are bound to run into legal proceedings - I had my share of that and I had a well known designer giving evidence for the state that in fact favored me based on the work done in that case. If you care to go to my website, you will see that I mentioned that somewhere for the world to see.
Everyone has his highs and lows and I am not different than anyone else.
I have nothing to prove to you or anyone for that matter and please do not threatens me and no, Im not sensitive in any way.

As for the statement not to interfere - who the heck are you:?: This is a public forum and I can place my replies where and whenever I can as long as it is well within the spirit of the conditions of this forum, and I would advise you to read those terms and conditions as I believe you had not done so by your remarks in some posts.

For more than 4 years I am a member here and I always tried to be constructive in my views and advise based on my hands on experience as a boatbuilder. Usually where I can I back my views with photos or spec sheets (which you incidentally choose to ignore)

If I may, your public profile do not impress me one bit, and I am of the believe that you are a cyber armchair sailor/hopeful boatbuilder antagonizing others in the know as can be deducted from this thread.
My challenge to you now since you tried to shut me down; do not hide behind a username (I use my real name), who are you, show your face (Im not shy of mine) so people can see. Show us some of your work (I do that regularly and my website available to all)

As a parting note: We regularly rolled 12mm Corten into conical sections at the mines, either by plate rolls and if the diameter was to small for the plate rolls, pressed the conical sections by press brake. Your statement in the previous post about rolling 6mm Corten just don't add up. The plate rolls should rolled the plate easier than the wheels and I assume you referring to the English wheel.

If whoosh or who ever he is continue to try and discredit me or anyone else, he will be a one man gospel choir as I said my piece. Everyone knows the saying about arguing with a fool.....

As to the starter of this thread, I apologize for this reply and the fact that this tread had moved away from its intended purpose, but it is obvious who distracted it.

 

oh shurrap wyn you are talkin to an old friend

 

Wynand has pretty much had the same thoughts about most of the post from which the quote is extracted. I will not say it again. Please see my response to your PM.

Whoosh, you have done a 180 degree turn-around. Early in this thread you favoured lightweight modern boats for offshore sailing. Here you argue in favour of heavy displacement and massive strength.

There is validity in all materials and all types of boats, each in its own place.

You are right, the steel 65 footers sailing the wrong way round the world did suffer oil canning. That is a special situation; who aside from a masochist will circum-navigate against wind and sea except to prove something? Those boats stood up to incredible punishment and did not break, they were slightly bent. Such voyaging is out of the ordinary and needs special design.

Whales are not the only dangers at sea. Boats must also be capable of sailing out of dangerous situations. A catamaran that is heavy cannot do so. Boats have more chance of running aground than hitting whales. The plywood cat that you describe would not be able to sail out of its own way nor beat out of a wet paper bag if built from steel. That would put it in serious danger if on a lee shore in a bay when bad weather arrives. It would also be at risk of being driven under by large waves in storm conditions. It is a safer boat for being lightly built. Yes, it could have been built stronger with carbon sandwich but that is beyond the ability and budget of most amateurs.

It is up to every skipper to sail within the capabilities of his boat. In the past even racing sailors sailed to hold the boat together, knowing that breaking the boat would prevent them finishing. Modern distance racing displays the opposite attitude. Boats are sailed at maximum speed almost irrespective of sea and weather conditions and it is only after they break that care is taken to hold them together. You are not going to find that mindset among cruising sailors. They are far less likely to break their boats.

Dudley

 

I don't know Whoosh...I tired of responding to this sort of talk along time ago. I am going jump in here, not because I think your mind is going to be changed about anything, but because there are others that are trying to decide who to hire to help them.
Either you are not as experienced as you say, or you have not payed attention all these years.
Boats are not boats. They vary in function and appearance as much as land vehicles. You seem to classify all of them, and test their worth with a few simplistic swings of the sledge.
In fact I will use land vehicles to show you how silly you sound.
Here, for example is a vehicle I might test with your sledge hammer. The bed needs to be able to repeatedly take the blows of 300 tons of rock on a daily basis...


Here is one where you would likely find the your sledge test would be pretty worthless...


As to your complaints about steel boats faltering when subjected to an extremely harsh environment in a race that is designed to test the human spirit and really verges on the absurd, take a look at this. I think it is just awful that these school buses can't make it around the race course any faster than they do without breaking down. What a poor design!



As to your harangue that building right side up is the only way to go is as naive as it gets. Whether or not you choose this is dependent on many things besides personal taste. The material and method you are building with, the nature of the build floor, the availability of turning equipment, the size of the boat, the overhead room in the structure, just to name a few considerations. Many, many companies that I have seen and worked with, that have some really bright fellas working in them, have chosen methods that differ from your "only way".

I suggest you step back a little and listen to some of the experience here. You have not found the way yet "Grasshopper"

 

I would like to pass on some information to the forum about whoosh. He has now told me his real name so I have been able to check back in my email files to find what was said.

You can read earlier in this thread how he said that he had contacted me and found me inflexible about my boats having to be built upside down. My emails to him in 2003 show that I told him exactly the same as I did on this forum. It is not up to me to dictate to builders what methods they use. I am flexible on most things. For some reason this man would like the boatbuilding world to think otherwise.

In 2003 he approached me and proposed that he write material for me to post on my website promoting and advising on building round bilge designs instead of multi-chine and radius chine hulls. Within 2 emails I could see that there was no room for us to work together. I told him that his ideas and mine were too far removed from each other so I declined his offer. In retrospect that was a very good decision.

He is posting under the name of "whoosh" but anyone interested can read many other posts by him under the name of "Lazeyjack". Of particular interest is the thread that he started about rudders on one of my cruising designs. I was not aware of this discussion until this weekend, or I would have posted a response. You can read the thread at http://www.boatdesign.net/forums/boat-design/comment-rudder-24258.html .

I am not so naive as to think that I am one of the best designers in the world but I am confident that there are not 10,000 better designers as he would like you to think. I doubt that there are 10,000 designers in the world, so that would put me at the back of the pack. Bear in mind that his opinion is tainted somewhat by me rejecting his offer to help me.

This man represents exactly the reason why I am very seldom found in the boatbuilding forums. It is not possible to conduct a reasonable discussion with such a person. They are very opinionated and will not accept contrary thoughts. They give inapropriate advice while insisting that they know everything about the subject. On top of that they are often abusive and destructive and they generally do so under a pseudonym. They can snipe annonymously at those of us who are posting under our own names.

The danger is that they do appear to be very knowledgeable to the newbie, who can be easily led off in the wrong direction. Taking the advice of someone like this is really no better than acting on the advice of an armchair sailor at the local yacht club bar.

The internet is a great resource for finding info on any subject that we can think of. The difficulty comes in sorting the good info from the bad. I am sure that this man has a lot of useful advice for visitors to the forum, if only he would be reasonable and balanced about how he offers it.

 

Mr Dudley Dix: I've always appreciated your designs for their rationality and search of simplicity. Your plans have excellent reputation for their quality, accuracy and precision of details.

Mr Wynand N: I've spent enough years in shipbuilding to see immediately in the pictures the quality of your work. The clients who give you a boat to build are lucky guys.

I agree with you that good plans like those from Van de Stadt are worth their price, as that eliminate further "shitty" engineering and wild guesses which can end in very expensive mistakes. The price of plans from a good NA is a very small fraction of the total price of a boat.

Sirs, do not waste your time with such people as Lazeyjack / whoosh. Simply do not answer, ignore them.

 

Bridges we were told are a very good analogy to boats when you think of structural materials and the results of failure. Lots of parallels-- usage-- loading --failure modes --materials--areas of operation-- user expectaions, the lecture got hillarious when we started talking about high -performance racing bridges but he was making a point.

If you want to build a boat that will be used by your great grand kids generation then there is only one material that is the real gift from God Weldable with 100% strength means heaps structurally.

We had some detailed lectures and a string of slides showing some very serious failures of alloy boats professionally built after extended periods of heavy weather. I think the enginers may not be as keen on this material as they are of steel for a host of reasons.

In the very educational 84 Sydney-Hobart 106 boats out of 151 were forced to retire. Out of the entire fleet alloy boats made up 14% of the hull construction material but these boats had 21% of the structural failures forcing retirement. They were second only to the Kevlar-carbon -fibre boats for structural failures attributed to their construction material.
Steel boats had zero structural failure and GRP faired significantly better than alloy, even foam cored GRP was tougher than alloy.
This lead to at least one insurance company putting up premiums for alloy boats.

Load cyclres in the weld zones is often the cause, but also plain outright strength where a lightly built steel boat might buckle a panel the alloy boat often splits a weld as well as buckling the panel, When one weld fails that can cause another to fail and so-on in prolonged heavy weather this can be very serious in a non -compartmentalised boat. In some commercial craft the bulkheads split away from the frames they were welded to as the boat wracked.

Resale prices for old used aluminium boats seem to be lower than their steel counterparts, brokers have had real trouble shifting older used alloy boats, becasue the surveyors are not kind to old alloy boats. Alloy also forms those ugly oxide scabs and little pits everywhere the salt water has been when it is unpainted. In warm salt water environments alloy boats are probably more corrosion prone than any other material unless well painted inside. outside, in tanks, stern tubes the lot. If the paint is breached the corrosion gallops underneath lifting it off in all directions and corroding with unleashed energy.

Alloy has not been very succesfull in the offshore blue water fishing fleet that operates in Southern waters and these boats are migrating back to steel, even some new boats have split long welds in bottom panels after only one season.
Some boats even have had to be re-welded extensively after delivery trips that met heavy weather.

Lazyjack said steel disappears...Poof ...but this is crap, it has a very slow and very obvious corrosion. Its Aluminium that can corrode fighteningly quickly given the opportunity, it is very high on the energy scale close to magnesium. It's only the surface oxide coating that stops it oxidising instantly in air and turning into a pile of powder. Just to give an idea of how reactive it is, In a high pressure pure oxygen environment if you scartch it with a piece of steel it ignites. I know this is irreleveant to boats but in the right circumstances Alloy really does go "Poof" or "Whoosh" and dissapears into a pile of powder.

 

Its interesting that a recent video put out by Cunard on the building of the QM2 , stated that besides from cost one of the main reasons was that the deck and super structure of its predecessor the QE2 was constructed from aluminium and now required signifcant remedial work. The QM2 was completely constructed in steel.

 

What a dark picture of aluminium...That almost make you believe that a number of NA and Naval Engineers are poor fools using that material. There are very good and long lasting boats in aluminium: the Pen Duick III (1966), the Pen Duick V (around 1971), Pen Duick VI (1972) are sailing today with no problems, a lot of fast catamaran ferries (Juan Patricio: 60 knots every day in the Mar de Plata, and many others), a big number of fast patrol boats in numerous Navies, plus dozens of fishing boats (the older I know has 30 years), yachts, pilot boats etc. Add all the super-structures of cruising boats in the Caraibes (a lot made in Finland) brief many, many boats using aluminium without special problems.

As always with any material it needs good engineering and craftsmanship and in the case of aluminium the good alloy. You will find in any material bad records of poorly designed and/or badly built boats that crack, split, and even sink.

About the QM2, the main reason was cost and nothing more.