Doug,
Aluminum is not maintenance free. In fact, it is exactly the opposite. Aluminum is extraordinarily reactive in water, both
chemically and electrically. If you really want a viable challenge in metal boat building, consider an alloy of copper based
stainless steel. There are several alloys to choose from. The advantages are that no painting is required ever, not even in salt
water and nothing grows on them. I know of a couple of commercial fishing vessels that were made in Nova Scotia back in the 70's.
They very successful, but expensive. The same challenges exist in construction as aluminum with a few more added, but the result
would be both unique and viable.
Steve

"DougC" wrote in message ...
On 7/22/2010 7:50 PM, Bruce in Bangkok wrote:

....
"Thinking outside the box" seems to be all the rage these days but to
be useful it really needs to include some consideration of "Why didn't
anyone else think of this bright idea"?


The main reason is just to make it look nice: I like the look of the shape of the plank hulls, but also like the
zero-maintenance aspect of aluminum.

Doing what I want would involve more labor than typical welded-aluminum boats--but for a leisure/hobby project with no pressing
schedule for completion, that's not really a "cost" as such.

And, finally, what would be the advantage of a welded aluminum, 15 ft.
boat over a wooden or fiberglass boat of the same size?


Mainly it's that I think I could do a better job building with metal than with wood or composite.

People getting into this probably tend to choose whatever method they are most-familiar with, and for most people that's
woodworking, because they have accumulated some tools for that to do around-the-house jobs. I have nearly no woodworking tools,
but a fairly big amount of metal-working and welding equipment.
~