Spark gap 'gap'...

TL> From: Malcolm Watts <MALCOLM-at-directorate.wnp.ac.nz>
TL> I am currently using a 25nF cap with a 12kV 60mA transformer. I can set
TL> the total gap length to about 1/4" before it ceases firing. There is an
TL> element of resonant charging going on in my system as evidenced by both
TL> the gap setting (around 12kV) and the <100Hz firing.
TL> Malcolm

Hi Malcolm & other coilers.

With regard to the above posting's specs,

Does anyone have an approximation of spark gap length vs required breakdown 

I have a 15kV/30Ma neon & can get more than 1/4" combined gap length. 
Increasing it to over about 1/8" gives no greater coil 'output' (except for 
the gap noise). 
Is this 'large' gap likely to damadge the transformer? The system is slowly 
being optimised as new parts are being constructed, It's my only 
transformer at present & don't want to pop it just yet!