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Troy, small boats in steel are not as common because of a number of factors. First is weight, second coatings cost and effort, and last is because of the first two; aluminum is often found to be less work and cost.
Steel is heavy so make the boat thin, but then you're welding very thin sheet which is not easy to keep a hull fair or wrinkle free. The Hunky is a skiff form (not a dory) and has large relatively flat areas that will be extremely difficult to keep clean/fair/smooth when final welding is done on thin sheet.
To reduce weight, naturally we'd thin the material more, and the small steel boat problems all become larger factors- yet.
Coatings are critical to any steel boat. The material has/may be/is wise to be purchased as 'wheel abraded' so that the sheets are actually primer painted while in the mill/distribution center. Then when complete, the material has to be sand blasted at least along the seams but more commonly everywhere.
Then a very decent quality primer and usually some form of coal tar epoxy are applied to allow the hull a decent life. If at anytime the paint is marred and the underlying material exposed; that area needs a spot re-blast and re-coat to avoid loosing the hull at that point. Remember its thin so it won't allow much rust- other wise the hull is heavy and the Hunky becomes a displacement cruiser!
When you initially compare aluminum and steel the steel is less expensive, but when you add the slow build, cutting and increased wit of handling along with blasting/painting/coatings labor; you exceed welded aluminum by twice or more.
In Holland they build lots of small boats with sheet steel but almost all those shapes are highly curved hull forms. They are kept reasonably fair by pulling the sheets into very contoured shapes and rolling and forming with an English Wheel, so the tension on the hull panels is greater than edge contraction when welding.
So.... steel is heavy,
to reduce wt you thin it out,
making welding 5x to 10x more difficult with much higher skill and
experience involved and
the main source of small welded steel boats almost
all make the boats in extremely curved cylindrical and conic forms
very different from a flat bottom,
straight sided,
skiff form of the Hunky form.
Once the Dutch get their steel boats done they blast and paint them and if the internet is any indication (?) they don't last 1/5th as long as welded aluminum.
The last item is strength, a welded aluminum, boat of 1/2 the weight will be about the same strength as steel.
If you skip the blasting, painting, super slow cutting and welding, and work in aluminum as you would in wood, (tools and cutting) then the result is less fuel for the longer life of the resulting skiff.
If you were pouring a few tonnes of ballast into a displacement hull form I'd say the increased weight was not a draw back, but the Hunky planes so I'd do it in wood or aluminum.
cheers,
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Kevin Morin
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