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Long live the cap (was : it died and I was angry!)

Greetings everyone,

After about 2 months of inactivity on the scene, I have what everyone
would consider great news regarding my own capacitor....  :-)

I had not tried the design before.  Series caps rated at a total of less
of the voltage?  Although I understand now how it works better, I did
not then.  Nevertheless, I was ready to try anything to keep those darn
things from dying all the time.  During early January, I was running the
Tesla Coil pushing almost the 70" of spark I have gotten before with
three caps in series, each a total of only 7500V rating (although thats
a conservative rating).  .018uF in total value.  Two weeks of work, and
$25 of poly.  (not to mention the $30 of PVC stuff I put it in)

On one late-night run, it blew the pressure cap, and as a raced toward the
control panel for an emergency shutdown, bright flashes of light and
lots of smoked poored from the cap.  By the time I got there it was too
late.

I figured that if one of the three caps failed, that meant that the other
two caps were hit with more voltage until they failed as well.  By the time
I turned the coil off, the sparks had dropped from full, to 2/3s, to 1/3rd,
then nothing, indicating to me that this had probably happened.  Doh!

Since I live in an apartment, and my Tesla Coil is at my parents house,
I didn't try it again until 2 days ago.  After a strong storm, my parents
wanted me to move my equipment out of the way in the garage.  I took
apart the capacitor PVC casing, only to discover that apparently, one of
the wires attched to the bolts through the PVC had gotten to close to the
other one, arcing through the oil from wire to wire.  As more and more oil
got toasted, there was less oil to replace the "carbon track" though it,
creating the ever destroying capacitor effect I had witnessed.  After
removing
the caps from the PVC, and placing them in another container, I found
they worked fine.  In fact, I enjoyed over an hour of almost continous
runtimes :
3 minutes on, 30 seconds off, that kind of thing (boy I hope this wasn't too
detremental on those caps....)

The moral of the story is, well, I don't think there is one, but I guess a
close
one could be :

Don't get too discouraged with these things that you ever just give up like
I
did.  They will provide you with a lifetime of entertainment.

Best regards,
Jeff Corr