Monster Cap balanced by Monster Topload?

To: tesla-at-pupman-dot-com
Subject: Monster Cap balanced by Monster Topload?
From: "Coiler" <mycroft-at-access1-dot-net> (by way of Terry Fritz <twf-at-verinet-dot-com>)
Date: Fri, 19 Mar 1999 11:52:43 -0700
Approved: twf-at-verinet-dot-com

I have been a fortunate person, and have stumbled into a pair of
wonderfully large caps. Unfortunately too large, unless someone
can give me some tricks.
Cap #1: 0.7uf 40KVDC Maxwell. I figure this, by itself is useless for
        tesla coil duty, but I am going to try and leverage into a duplicate
of..
Cap #2: 0.2uf 125KVDC. Manufacturer unknown. Used in some physics
experiments

Since I am in the process of building an 8.5" coil, I thought that the .2
unit
would work great there, until I ran the numbers, and found that even with a
6"x60" topload, I could only tap in about 4 - 5 turns. If I recall, bigger
is
better on the primary inductor, so I can control the surge impeadence of the
primary tank.
So.
How do I boost the capacitance of the secondary without having a topload
larger
in diameter than the streamers I would be throwing? I am assuming something
like stacking toploads, the questions then are:

1) Inter-toroid spacing - how close/far apart need I make them for the best
    capacitance, with breakout still possbile
2) How could I compute approximate C value for each additional toroid?

[Even getting the cap size down to 0.1 shows I need only 7 turns :/]

Charging system is capable of delivering 500ma at 14.4KV, so I don't think
I'll have a problem running it (I could be wrong)


Michael Baumann
Coiler, Homebrewer, Nerd. mycroft-at-access1-dot-net