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main caps and rsg's vs static gaps



Hi to everyone from Oz!,

 I have been reading the 'list' and the archives for some time and have
got some questions of my own that have probably been in before however,

1) I have been slowly assembling parts for a coil and have a 13800kv
0.36 A pole pig (5KVA). Now according to wintesla I require a main cap
of 0.083uf - this is a big cap!. I have made a flat cap of 0.026uf using
1.5mm aluminium plates and 1.5mm ldpe. I don't fancy my chances using 3
of these caps in parrallel to approach the required capacitance required
and still withstand the peak voltages generated. Ques is  - Is the cap
value determined by the ability of the transformer to fully charge it
based on a static gap the will fire 100 bps, (OZ = 50Hz). If so, would
building a rotary gap allow me to fully charge a smaller value cap,
(i.e. 3x0.026uf in series = approx 0.01uf but better voltage capacity),
and allow me to fire the cap much faster than 100bps thereby still
allowing me to fully utilise the KVA rating of my transformer.

2) If so, a) will using a smaller cap X say 400 bps give me a comparable
result, (spark length etc), as compared to larger cap x 100bps?
             b) Is there any effect on the resonance of the primary in
using a smaller cap x faster breakrate as compared to the static gap
alternative?
             c) Is there a formula for this, i.e. rsg's + transformer
ratings + cap and resonance?

3) with reference to rsg's , this implies from my point of view anyway
that for part of the input waveform there would be insufficient voltage
across the sparkgap to initiate a firing. i.e. instead of charging for a
full half wave there would be multiple chargings/firings per half cycle
- what happens near the point where the waveform passes through zero
potential?

 My apologies for what may seem basic questions, I would sincerely like
to thank the many contributors to the list as you have already saved me
countless wasted hours on a project I have spent a long time on already.

 Kindest regards

 Robin Copini,
 Adelaide South Australia.