What are the disadvantages of having steel hull? Could you compare the pros and cons of steel or aluminum versus fiberglass?
Mark Matthews responds:
First, entire books have been written on the subject, so I won't pretend to throughly treat all of the pro and con arguments here, but I can set up some guidelines. Steel hull boats are incredibly strong, for one. There's a reason commercial ships are made out of this material. It's relatively easy to fix, especially if you should find yourself far a field. Welding is simple and common in just about every country in the world. Should you encounter enough force to dent the steel, it will deform for a long time before failing. For a firsthand experience, here's a piece by John Kretschmer, one of our authors who just happens to be a steel boat owner, Rust Never Sleeps.
As far as disadvantages, rust is one. Zincs on a steel boat are critical, as are prepping and painting over any spots that may be exhibiting oxidation. Steel is heavy, and while steel boats typically thrive in a brisk breeze, they can suffer in lighter airs. Aluminum has many of the strength advantages of steel, but is lighter, which means faster. However, electrolysis is even more critical on aluminum boats, and bottom paint and aluminum hulls are another subject altogether. Welding aluminum is also a trickier affair than steel, although as a side note I have a friend who showed me wood working tools can be used on aluminum-he used a circular saw to cut his keel off after he found out the lead in the keel was reacting with the aluminum of the hull. An interesting sight to say the least. Fiberglass is strong and prevalent and relatively easy to work with-depending on the kind of work and your tolerance for holding a sander over your head, see Blisterama Battle RoyaleSurviving the Haulout, though not as strong as aluminum or steel, and it will crack on impact rather than deform. Blistering is the Achilles heel of fiberglass boats, although a well-cared-for hull will give many decades of service.