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Question regarding first (small) coil



I've finally got round to begin construction of my first coil, using a car
ignition coil as a 
PSU. I have no idea on the output, but I imagine it is about 12-15kv -at-
50-60W. The primary is 10 
turns of 1mm ECW in a flat pancake formation, and the secondary is 880
(approx) turns of 0.125mm 
ECW wound around a 1 1/2 inch pvc pipe. I am planning on building a
polythene sheet/Al foil stack 
type capacitor, if I can find a suitable thickness of polythene sheet (the
output from the 
ignition coil blasts straight through any plastic bag thickness material). 

My question concerns the capacitor. I understand that it is important to
put a bleeder resistor 
in parallel with the cap for safety when the coil is not in use. What value
and power rating 
would be desirable in this case?

I have also been wondering about building an MMC. Would HV Ceramic Caps be
suitable? The ones I 
have in mind are from RS components (UK), rated at 1000vdc 0.01uF, and cost
£0.18 each. 
Unfortunately, the catalogue gives no information for high frequency
(>1khz) operation, the 
dissipation factor is 1.5% at 15v rms 1khz. 

Regards,
Ben