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Paolo Zini
 
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Default Aluminum stitch-n-glue


Awhile back, there was a thread concerning stitch-n-glue using aluminum
rather than plywood. Although I do not believe it could be a high enough
quality solution to boat building, having a hard time believing in the
reliability of the epoxy bond and believing that welding is just as easy

if
not easier, it is an interesting topic that I'd like to read about.


I am interested in the subject, only for curiosity reasons, but I am
interested...
I have made some google search on the aluminium-epoxy subject.

I try to explain what i have found:

-Direct use of epoxy on Al don't work, mainly because Al is covered by Al
oxide, and epoxy don't make reliable connections to the oxide layer.

-epoxy and Al are usend for airplanes on a regular basis. To overcome the
oxide problem, the Al is treated with some chemical primers (sorry,
forgotten what) that replaces the oxide with something more reliable.
The use of the proper primer make structural gluing of Al feasible and
reliable (at least for planes...)

-It exist one alternate method for structural gluing of Al, that looks
feasible for "normal" homebuilder

-Epoxy glued Al isn't used (for what I know...) in ship building. It must be
a reason for that, but i don't know it...
Anyone know one explanation? I am curious.

I was thinking that one Al lapstrake hull would be one interesting solution
(maybe also appealing?) for one homebuit epoxy glued Al boat...
Panels hare simple, no special machines is required, the glue surface is
large...

Paolo

From Pisa, Italy