6" spark

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Original poster: "Shaun R. Phelps by way of Terry Fritz <twftesla-at-qwest-dot-net>" <shaun-at-visorloop-dot-com>

Hi,

Just given my coil its first run.  It was mostly a test run because I
couldn't wait until all the parts had been properly built.  My specs are:

Primary: 0.25" flat copper tube spiral (14 turns)
Secondary: 22AWG 4" by 16.5"
Topload: 2 salad bowls
Spark gap: 2 copper electrodes with a fan underneath
Tank Cap: 12 beer-bottle SWC
Input: 9KV 60mA NST.

I was able to attain a 6" spark from this, not very impressive.  And, holy
gajeebers!  This thing is loud!  Today I'm going to make a Richard Quick
spark gap with a fan.  I'm hoping that will quiten things down and make a
bit of a difference in spark length.

I have used no protection on this whatsover.  I am considering putting a
safety gap on the NST but am not sure if I really need this.  Is NST failure
a common thing on such a small coil?  Will a safety gap really help?

Any suggestions on creating a bigger spark?  I have plenty more NST's
available to me, but would prefer to have all other components working at a
good efficiency first before jacking up the power.  Realistically, what size
spark could I expect from such a setup if it were running at a good
efficiency?

One other thing.  I notice on my SWC that there is arking in one of the beer
bottles.  The spark is actually inside the bottle.  I can't understand why
there would be arcing inside the bottle.  All that is inside is a brass
electrode and the salt water.  Since the electrode is already touching the
water, I'm not sure why I would see sparking.  Of course, I don't want to
stick my head close to this thing while it's on for further examination ;-)

Appreciate all the advice.

Shaun R. Phelps