Ignoramus12347 fired this volley in
:

Lloyd, now, if this transformed was heated in an oven to burn off the
varnish, then it would all separate, right?

Not really. If they are interleaved, every lam would be fastened to the
next by a layer of carbonized varnish. The whole purpose of vacuum
varnishing is to ensure that it penetrates every gap (even between the
laminations) of every part.

Partly, it's for the insulation qualities of the varnish, and partly for
mechanical integrity. After vacuum-potting, they bake out the whole unit
until the varnish cures. They generally use a varnish known generically
as "Hi-solids", although there is (was, anyway) a commercial product
called "Hi-sol" varnish specifically for the purpose.

I'm pretty sure, when a scrap yard wishes to "pull apart" a transformer,
they end up cutting something -- either the coils (easy) or the core (not
so), unless they're gapped-core units. You can easily tell. Just look
at one end of the "I" pieces. If they're ALL together in a single stack,
and all the "E" pieces are together in a single stack, then it comes
apart easily. If not, you cut.

It's really not as big a task as you're making it out to be. You can cut
the coils out of those in an hour. You could have cut them and had them
out in the time it's taken to ask these questions.


Lloyd