Dr G,
I only used the 2024 as an *example* of harder aluminum alloy versus the
much softer belly skin aluminum alloy such as 0 which is very heat
treatable, workable, etc. My intention was not to say that 2024 *should* be
used at all in this or any other case. What *should* be used is sheetmetal
that is "as strong or stronger" than the original sheetmetal so that you may
retain at least the original strength of the design.
My use of "pure aluminum" was only to try and say that as compared to the
aluminum alloy sheetmetal 2024 the '0' aluminum sheetmetal was as pliable,
treatable as an almost pure aluminum sheet of metal. In no way was I trying
to say that '0' aluminum sheetmetal was "pure aluminum" -- lost it in my
choice of words I guess.
I'm very familiar with all the grades of aluminum alloys and I also have
lots of experience in building aircraft parts both for airframes and
powerplants. My licenses say so along with my years on the job maintaining
aircraft bodies and engines. ;))
Best,
Tom