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70kv system questions



Original poster: "Jonathan Peakall by way of Terry Fritz <twftesla-at-uswest-dot-net>" <jpeakall-at-mcn-dot-org>

Howdy All,

I am building a small coil, a 70kv system from John Couture's book. I am
having some trouble getting it to break out, and am hoping for some
advice.

System:

150 watt 120/12vdc power supply
Ignition coil wrested from a '62 Falcon
Potter and Brumfield 12v relay, # K10P-11D15-12
470vac, .068uf and 50v 1000uf caps
Bolt and acorn nut style spark gap, mounted on plastic cutting board
material
12 turns #12awg auto wire wrapped on a 3" x 5" form (Book calls for 5
1/4")
Aprox. 468 turns of 24 gauge insulated magnet wire on a 13 1/4" x 3 1/4"
form (Book calls for 3")
4 x 7.5kv .001 uf caps hooked together with two in parallel and two in
series to theoretically produce .0025 uf.

I was having trouble finding the correct size forms (I live in a town of
368, so the hardware scene is a little limited) so I went ahead and
coiled as listed above. As well, I coiled the secondary out of what I
thought was 24 gauge (I had the wire I laying around from a radio
project), but then when I measured an inches worth, it became apparent
that I would need a longer form that the book called for, so I figured
it must actually be 22 gauge. As it would take days for me to get more
wire  I went ahead and wrapped it anyway. Today I got some definite 24
gauge, and it measures out the same as what I have already wrapped. Hmm.
I don't have a capacitance meter (ordered one, not here yet) so I can't
verify the hillbilly primary capacitor system.

I have tried a number of discharge sphere configurations, from a 1"
brass door knob,  2" and 2 1/2" aluminum foil covered balls and a copper
toilet float. I have tried insulators from 1/2" to 3". I have also tuned
the spark gap and primary coil. I have raised and lowered the secondary
relative to the primary, and spaced the primary wires a little, which
seemed to help. Regardless of what I do, all I can get is a little
corona from the bare end of the secondary coil wire, or 1" to 2"
streamers to a metal object.

My primary suspects: 

Are the coil dimensions too out of whack to work?
Is the 22/24 gauge thing a big deal?
Spark gap is a little erratic. Is this a huge factor? (Making a new one
already)
Any way to test the ignition coil with a VOM? It *was* still running the
Falcon...
Primary caps are obviously suspect. Do my numbers add up in the first
place?
Relay sounds a little different after some use. Have been doing fairly
short runs, but it has gotten a little hot once or twice.

Anyway, thanks for any and all help.

Jonathan Peakall