De-potting and re-potting a pole pig: Insulation concerns.

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Original poster: "J. Aaron Holmes" <jaholmes@xxxxxxxxxxxxxxxxxx>

I had long ago dreamed of creating my own version of
Dave Leddon's "Visible Pig" (don't know where those
pictures of it are...Dave?), but the 15kVA unit I
dragged from its can ended up being stripped down and
its core donated to ballast science :)  I now have an
old beater of a 15kVA unit (my workhorse) and a newer
25kVA unit.  The 25kVA unit has, I'm sad to say, been
unemployed since I acquired it a year ago, and only
just this last weekend did I finally pop the lid to
see what a modern 25kVA unit looked like inside.  It
was really quite handsome, and got me re-interested in
the "Visible Pig" idea.

However I've managed to get myself a bit paranoid now:
 If I lift the thing out of oil (a big *if*
considering I don't see any viable attach points on
the thing), am I seriously compromising its insulation
by letting the oil drain away from the windings?  What
about the inevitable air bubbles what will become
trapped under the thing when I lower it into its new
home?  Will they be problematic?  My gut tells me that
a few tiny air bubbles are probably no big deal given
the dimensions of the windings, but I have no
experience to base this on.  I know that air bubbles
are "the end" for oil-filled capacitors...  What do
you all think?  What do the transformer rebuild places
do?  Are the cans momentarily evacuated to get the air
bubbles out, or what?  Hmmm...

Best Regards,
Aaron, N7OE