Brent Swain
N/A
Search "Law of Mechanical Similitude."
No comparison between big ships and small steel boats , structuraly .
Steel boat as a long-term liveaboard (in a warm(er) climate).
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Search "Law of Mechanical Similitude."
No comparison between big ships and small steel boats , structuraly .
Brent Swain
N/A
i saw a 30 footer hauled out in Auckland with a clean break where his encapsulated lead broke free of the hull. Luckily, it had been glassed over inside. People were saying "If anyone needs lead ,there is a 5,000 lb lump of it on St Helliers reef."
I see a whole lot of plastic boat fixing around here, due to leaks and structural shortcomings. As much as the steel boats ever do.
Steve ( search Silas Crosby) wisely flame sprayed under and around his windows, a potential problem spot from condensation on his ports.
Lately, I have been thinking, a strip of stainless welded there , to keep condensation from getting under the foam or firing strips, may eliminate the problem.You would only need it under the port.
I once worked for a client who had found a stainless opening port for the front of his wheelhouse. We were able to remove the glass and weld the frame,corner to corner, to the steel wheelhouse front, eliminating any hidden areas, probably eliminating any problem there.
Perfectionism is a screwup. All it takes to minimize maintenance on a steel boat is simplifying to eliminate as many corners and inaccessible areas as possible, trimming all outside corners with stainless, and a good , clean, sandblasted surface , zinc primed above the waterline, covered with many coats of thick epoxy ,followed by something more UV resistant, for a top coat, and many thick coats of epoxy inside. Any place inaccessible should be done in stainless.
Search Tagish for a good circumnavigators blog. Great photos too.
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Brent Swain
N/A
I make ten dollars a book, a tiny fraction of my income. I am retired from building, and only post to help people out, and pass on what I have learned, in over 4 decades of steel boat cruising ,living aboard, designing and maintaining steel boats.
I have never seen single weld break on mild steel on small cruising boats, ,ever, including some horrendously bad welds. That is a plastic boat advocate's myth.
No we will never know how many plastic boats have sunk in mid ocean from collisions which a steel boat would survive with no risk whatsoever.They simply "go missing." I do know for sure ,I would have been one of them, had I not been in steel , as my friends have also stated.
A cruiser in a steel boat with no liferaft ,is much safer than a plastic boater with a liferaft. Life rafts cost a lot of lives in the 79 fastnet race.
Robin
Well-Known Member
Unlike you, I do not keep preaching on and on and on ad nauseam and using mostly anecdotal information where it relates to anything not steel. I DO see you have some valid points but you just do not know when to stop because you are doing your argument more harm than good. Tough to hear perhaps but nevertheless true as some at least have shown in their responses. I believe you have been driven off several other forums which whilst unfortunate, even reprehensible, is also understandable. I Make noclaims for sailing feats nor prowess unlike you but I will always stand firmly for having an OPEN Mind and listening to the opinions of others. There are no laws that say you have to accept other points of view, the same goes for those listening to yours.
Have a good Christmas wherever you may be rusting ( sorry couldn't resist
)
Kelpie
Well-Known Member
Ok, I'll bite: Brent, if steel is so clearly head and shoulders above any other material, why do the big volume builders use GRP instead?
rogerthebodger
Well-Known Member
I will answer that one.
One time boats were built of wood which is very labour intensive requiring quite a lot of skill
Then boats were built of ferro cement where the skill for the steel frame construction was also labour intensive but required a lower skill level until the plastering
Then came GRP construction over a simple frame like ply construction but requires skill and was labour intensive.
Then the molded GRP construction which required skill and labour to make the mold but then the hulls cam be made quite quickly with a lower skill level. This reduced the cost of construction as it could be made in a "production line" type factory.
Today complete GRP boats are produced quite quickly and at a lower cost due to production line techniques being used as the car industry made cars a lot cheaper with limitations customisation.
Steel cones into the "jobbing" type construction when it is not easy to mass produce and becomes a low volume construction and thus more costly.
Also today we have gone away for the DIY boat construction as was the case in my younger days and people want it all and want it not and as less inclined to do out a build it themselves.
This is in my view why GRP boats are very popular.
As for steel boat construction. It requires quite a high level of skill and heavy lifting equipment for a boat of amy size. It also needs equipment that at one time was not in the normal DIYers tool kits now its lesser so. As a time served degreed mechanical design engineer I find it easy and have the skill from my long years in mechanical engineering. Not all people have that.
Its also human nature to defend you choose when "attached" as Brent has in effect. I view is it your choice and it not up to me to change your mind and in fact it could be considered offensive of me to try to change your mine all I do is point out my reasons for my choice then its up to you to consider then in terms of your own context.
Brent unfortunately in my view does do a bit too for some.
Frank Holden
Well-Known Member
About 20 yachts overwintered in Puerto Williams in 2017... steel, alloy, grp, timber.....
The yachts in the charter trade to the peninsula , which are between 45 and 70 foot, are almost without exception steel or alloy. The one exception was an Ocean 60 that was down here for a few years.
Cruising yachts? ((EDITED BIT .... Cruising yachts going through the Channels ... not to the peninsula )) As many grp as metal and more alloy than steel.
One thing I have observed in recent years is a reduction in the number of Aust/N Am/ and UK yachts with the majority of boats being from continental Europe. Another observation.... of any single class Ovnis predominate these days.
Seems many Ovnis aren't insulated , one just returned last week from Montt having gone up through the channels in the autumn. She has no insulation. Not my idea of fun...
Me? Ive been in Pto Montt and southern Chile since arriving from NZ in 2004 - apart from a spell up around BA , a couple of Falkland trips and a trip to NZ and back in May 2014/ Feb 16.
My GRP Sealord has given a good number of smacks to terra firma in that time... hasn't fallen to bits and sunk yet...
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jordanbasset
Well-Known Member
Robin
Well-Known Member
Or a certain poster's steel boat:biggrin-new:
lpdsn
Well-Known Member
prv
Well-Known Member
Talk to the Mollymawks, Nick and Jill.
Since they are also fans of steel, there’s even a small chance you might listen. Fans, mark you, not rabid zealots - they’re happy with the trade-offs of steel for their purposes, but don’t pretend it’s a wonder material with no downsides.
They bought their boat as a bare hull in South Africa, and during fitting out they had some plating unexpectedly come apart at the welds. They checked a sample of the other welds, and determined that the entire shell plating was almost certainly faulty. They proceeded to grind out and re-weld, in sections, the entire hull. And the reason they were determined to do this, despite all the effort on welds which looked ok to the naked eye, is because they had recently seen this boat belonging to their friends:
It had hit some rocks, and in most places was merely dented - steel is strong, as we know. But one full plate in the bottom, amidships, simply popped out due to faulty welding and that was the end of the boat.
They were also alarmed when they spoke to a steel yacht designer (no, I don’t know who) about their discovery - he said not to worry, he had only known one yacht to break up at sea due to faulty welding. Obviously this was not acceptable odds for Mollymawk, hence all the re-work.
So that’s one complete break up, one bottom plate fallen out, and one section come apart when lightly knocked about during fitting out. All due to faulty welding, of course - no argument that a competent operator’s work would not do that. But most amateur builders are not expert welders when they start their projects - and the nature of the job has them doing most of their learning on the major hull welds that hold the boat together.
Most are fine, of course. But not 100% all.
Pete
Brent Swain
N/A
I have seen beautiful looking mig and tig welds break, having very little penetration ,but never stick welds. Tig and Mig needs flat calm, dry conditions, and super clean metal, which is what makes a building site for an aluminium boat so expensive, altho one friend built a beautiful departure 40 in aluminium, outside, by picking only perfect conditions for welding .
Took him a long, long time.
Stick welding is extremely forgiving of conditions ,and can be done anywhere, with no chance of weld failure.It is also the cheapest. The first 36 I built was welded by a first time welder. It pounded for 16 days on a west coast Baja beach in up to 12 foot surf, and was pulled off thru 12 ft surf, with no weld failures of any kind.
Took him a long, long time.
Stick welding is extremely forgiving of conditions ,and can be done anywhere, with no chance of weld failure.It is also the cheapest. The first 36 I built was welded by a first time welder. It pounded for 16 days on a west coast Baja beach in up to 12 foot surf, and was pulled off thru 12 ft surf, with no weld failures of any kind.
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john_morris_uk
Well-Known Member
So we've got an advocate for no liferaft. (The law of mechanical similitude isn't relevant by the way.)
And a suggestion that stick welded joints never break.
And you expect to be taken seriously.
The only serious thing is the seriously big hole you're digging for yourself as your suggestions become more and more outrageous.
Brent Swain
N/A
A friend had a 35 ft steel endurance. He complained about maintenance, so I suggested he cut off all the welded down steel dorade boxes and deck boxes, drastically simplifying things ,making them out of removable stainless or aluminium. He said that drastically reduced his maintenance.
Simplifying can drastically reduce maintenance on a steel boat.
Simplifying can drastically reduce maintenance on a steel boat.
Kelpie
Well-Known Member
Brent- still curious about why you think steel isn't adopted by the big volume builders?
Robin
Well-Known Member
Yet you wee advocating welded on bits prevents corrosion that bolt on bits, as many commercial builders do caused were you not.or did I dream that bit of selective explanatory
Brent Swain
N/A
Many of the lives lost in the 79 Fastnet were lost because people took to liferafts prematurely, and died, while the boats were found afloat later.
Had they not had liferafts, they would have survived.
Moitessier had no liferaft ,but was safer than people in plastic boats with liferafts. His circumnavigations were extremely trouble free, compared to doing it in plastic. Compare it to Web Chiles experience, in his book , Storm Passage. And you say Bernard had it all wrong for not following Chiles's route?
Credibility problem!
Read Calahan's book about weeks in a liferaft. Then imagine it in colder climes. Had he had a steel boat, he would have never ended up in a liferaft.
( Much wiser).
Most steel boat owners I know consider their steel hull their life raft.
No ,one is not safer in a liferaft, over a sunken plastic boat, than in a slightly dented steel hull ,still sailing, as you imply.
It is you who have the credibility problem.
A tanker will break in half if you load it unevenly, and will break in half in dry dock, if the supports are uneven. Definitely not the case with small steel boats, not by any stretch if the imagination.
Why ? Law of mechanical similitude! Very relevant!
By comparison , a small steel boat is grossly over strength, compared to tankers ,which are very marginal , strength wise.
You can ram a beer can, with a super tanker, without even denting it . Not the case in ramming another super tanker.
Why?
Inertia ,and law of mechanical similitude.
How do you compare the strength of a stick weld to a copper fasting in cedar every 6 inches, ( wooden boats held together by friction between the fastenings and the wood) or plastic decks virtually glued to plastic hulls, or the glass fibres glued together with polyester resin, a very poor bonding agent?
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Brent Swain
N/A
Welding is the best bedding compound ever invented. The space between surfaces, as you get bolting things down, is a major rust trap. Welding seals that space permanently.
Where you have to bolt things down, like sheet winches, flush weld in a stainless surface to bolt them onto.
Brent Swain
N/A
Grossly outdated building methods from the 50s has made steel non competitive ,price wise. A client had a quote from a commercial builder for one of my 36 footers, and was quoted $250K for just the hull and deck, which my methods have enabled me to do for around $17 K.
For what the vast majority of owners use a boat for , 3 weeks vacation , and the odd weekend ,plastic is definitely superior. For full time cruising as a way of life, often well off the beaten path, where steel is superior, the market is extremely tiny.
Brent Swain
N/A
Another common screwup on some steel boats is trying to imitate the hollow cockpit coamings , so common on plastic boats, making easy access to cleaning and painting hard to do ,or impossible. Any part of a steel boat on deck should be easily accessible to a angle or die grinder and paint brush.
Different materials need to be designed to different priorities.
Different materials need to be designed to different priorities.
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