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[TCML] Hello again

I've been an on again off again member of the Tesla list for over a decade.
Just want to say hello to my friends old and new, and ask a question.

I'm constructing a pair of transformer assemblies, each consisting of two
microwave oven transformers with the primaries wired together anti-series,
and the secondaries in series, thus allowing for about 4200VAC out of each
unit, for 240VAC in.  One leg from each MOT secondary is grounded to the MOT
chassis, and both MOTs in each assembly are bolted to an aluminum plate,
such that the plate floats like a center tap for the secondaries.  The plate
is electrically isolated from the housing, a .223 ammo can, using nylon
spacers which clamp around the Al plate.  My intention is to immerse the
transformers in oil, Vaseline, or wax, as one of the transformers in each
assembly will be subjected to twice their designed dielectric stress when
the lumped secondaries of each assembly are wired in series, and I'd also
like to entertain the possibility of adding two more such modules to the
series chain in the future.

I wanted to know if anyone has constructed a similar device, using
ammunition canisters.  They are equipped with substantial-looking seals, but
I don't know if they are oil-proof.  It would make sense that they should
be, as oil is often used to deactivate ammunition, but I'd like to learn for
another's experience if this has been attempted.  Also, I'd like opinions on
whether canning wax would be sufficient in this application, as I'd just as
soon not have to deal with leaking transformer oil.

I've hi-pot tested one of the assemblies, and in air, the floating Al plate
shorts to the grounded ammo can at around 7KV.  This is before deburring the
edges of the plate, and rounding the corners (the discharge point was always
the same plate corner).

Electrical connections will be realized through the use of ceramic
feedthrough insulators for the secondary terminals, and homemade plastic
feedthrough insulators for the primary.

Aric Rothman
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