Join Date: Feb 2000
Location: Annapolis, Md
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Steel vs Fiberglass
This is exerpted from a previous discussion on this matter;
As I have said before, I am not a fan of metal boats. Compared to wood or glass I think they are way too heavy for the strength achieved and too difficult to maintain. They are noisy and prone to have problems that are not easy to get to and repair. For the distance cruiser any bonehead can carry and use glass or wood to repair wood or glass boats anywhere in the world. Welding a metal boat in some atoll on the backside of no-where is another story.
There is a relatively small market in this country for metal boats; a bit in ignorance and a bit because metal boats really do not make sense for the venues that most of us sail in. While cruising people are a bit more open minded toward metal boats, I think metal boats will be a hard sell in this country for a long time making resale a bit difficult. Many of the metal boats that we see over here are crudely built hardchine affairs. The chines are often laid out without care for their visual impact. Cabin and deck structures are often rather primitive. Hardware is often painted galvanized steel. As they age they develop areas that have been dented in between ribs and other framing. It is not to say that there are not well built metal boats, but the perception of metal boats comes from the poor examples.
Amongst the proponents of Metal boats, much has been made of the ability of metal boats to bend rather than puncture. I think this is a little bit bogus. That may be true of the extremely heavy boats designed to workboat standards, but not really true of boats built to meet yacht standards which tend to be much lighter. These lighter weight metal boats use lighter weight skins spanning between a more closely spaced frame and stringer system. If the impact is on a frame you are more likely to bend the boat than puncture the skin but an impact next to a frame or between a frame is more likely to sheer the skin than bend it in any impact that would be hard enough to puncture the average fiberglass boat.
The one advantage of steel is a higher abrasion resistance. In the unlikely event that you end up rubbing against a rock for hours on end without puncturing the skin, a steel skin can withstand abrasion better than glass. If you sail in an area where abrading against rocks is a serious problem then steel may make sense. I doesn''t for me.
Metal boats are seen as being very durable, but again in the weights of materials used in yachts I seriously question that idea. All boats flex; it is only a mater of degrees. Over time this flexing work hardens and fatigues the steel especially the skins at frames and other hard spots. Rust, mostly from the interior makes the skin thinner. Like any other material each boat has a real lifespan. It may exceed our own but it may not. It is true that fiberglass will also fatigue and weaken over time especially non-cored hulls which tend to flex more. It is true that cored f.g. hulls may eventually delaminate from the core or the core itself may sheer but in well-built boats this is a very long-term process.
In a number of studies that I have seen over the years, steel is generally seen as being the most maintenance prone material out there, both long and short term. This is slightly offset by some of the exotic steels being used in the last couple years but for the most part, just like wood you need to keep the actual hull and framing protected from water and air. Unlike wood this means both inside and out. There are areas on a steel hull that are inaccessible but just because you can’t see them that does not mean that they aren’t deteriorating. Rust never sleeps and metal boats actually deterioate mostly from the interior out.
Then there is electrolysis. This used to be the kind of problem that was a compelling reason not to own a steel boat. In the early 1970’s I worked in a boat yard that had to do an emergency hauling of a steel power boat to prevent it from sinking. This boat which had been launched weeks earlier in perfect shape had changed slips and was tied up next to a boat with an improperly grounded 110 electrical system and in a mater of days the bottom of the power boat in question had lost sufficient thickness and was covered with small pin holes that the boat needed entirely bottom plating. This kind of loss was not covered by insurance. Today, there are ways to completely combat the electrolysis problem but, in my mind, they are bandaides treating symptoms rather than real cures to the problem.
My biggest gripe comes down to sailing ability and how this affects deck and cabin materials. Some of this goes away as the boat gets to be 45 feet or bigger. In boats under 45 feet, steel hulls are just plain heavier for a given strength than any other material except perhaps ferrocement. Weight in and of itself has no advantage at all. More weight means that you need to have more sail area for a given speed and a given sailing ability. More sail area means that a boat needs more stability to be able to stand to this bigger rig which means more ballast which means more weight which means more sailarea. The problem gets worse because steel boats often have steel topsides, steel decks and steel deckhouses. This is weight high above the center of buoyancy and as such reduces stability further making it hard to carry a decent sail area to weight ratio. In the ultimate bad sailing day, it also means that once inverted you are more likely to remain inverted longer. This problem is often addressed by the use of wooden deck and cabin structures. Deck and cabin structures are the area of greatest maintenance in a wooden boat and so you are just upping the amount of manitenance even further.
To answer your question fairly I probably need to explain my own tastes and preferences. In fairness, I must point out that puncture resistance has never been a criterion by which I select a boat. My personal taste leans toward lighter boats. I have always been a proponent of buying a boat suited to your anticipated sailing conditions and in my case my sailing conditions are strictly coastal and do not include passages to remote areas. If you are looking at passages to the remote areas of the Pacific Southern Ocean, then puncture resistance becomes more critical and the ability to make repairs in a remote area becomes even more critical still. You may also sail in a windier environment that I and maybe able to tolerate a heavier boat.
No matter what material you use, workmanship and quality materials will be critical. I do not believe that steel tolerates poor quality any better than any other material and since so much depends on the welds the welding needs to be top notch. Steel is not just one material but a family of iron based materials. How the metal is made, purified and alloyed affects initial strength, fatigue qualities and its resistance to corrosion.
You often hear that steel can be built cheaply. Quality metal construction never was or is cheap. You could build a quality boat in almost any other as cheaply or for less. With advent of computer driven cutters and the more common availability of some of the newer (last 15 years) welding techniques steel has come down in price to the point that custom steel boats maybe less expensive than custom boats in many other materials. The problem in saying steel is cheap is that simple hard chine steel boats with workboat levels of finish are often compared to yacht quality boats of other finishes. Probably a comparable and less expensive construction is glass over sheet plywood. Properly done this can actually be a far stronger and less puncture resistant material than steel. Glassed inside and out with quality laminates and epoxy resins, the plywood boat would have far and away less maintenance costs and would have a much lighter hull weight than steel, thereby having considerably better sailing characteristics in all ways.
I think much of the answer in picking a metal boat comes from picking the right designer.
At the risk of sounding like a broken record, most of the questions in sailing have no one right answer. That does not keep people like me from having strong preferences and opinions. My opinion suits me, and the way that I choose to sail, very well. It may not suit you at all. It is easy for someone to refute my opinion on some other criteria than my own. As I have said before on this BB, ultimately that debate can have no more substance than a trying to prove that Vanilla ice cream is inherently superior tasting than strawberry ice cream, (which is why these are called ''opinions'').