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Please Help Me Prepare for BIG Coil



	Okay, it seems to be the going trend nowadays that everyone builds the
biggest coil they can fit in their budget.  I am no exception.  I'm the
builder of the Veretus Coil ( http://spud.pureinsanity-dot-net ), and I'm
fairly proud of it.  I'm only a 17 year-old highschool student, I've only
built two real working coils, and I've only been a coiler for about 11
months now.  That is mainly because, as a highschool student, the only
money I have comes from my 'very' part-time job. 
	After searching for months on end, my partner and I found a place only a
few hours drive away that would sell us a new, single phase, 120v in,
14.4KV out, 10KVA pole pig for $150.  I'm not going to pass that deal up
after all the time we've spent looking, even though I still need to learn a
lot about upgrading our coil to handle the additional power.  Now, here's a
pretty comprehensive rundown of our current coil setup:

------------
27 Foot extension cord we built ourselves out of 10-gauge solid copper
housewire to run from the wall-plug in my garage out to the driveway.  It's
actually three-phase cord, but we just didn't use one leg.  The 50 foot 13A
extension cord we were using was starting to pose quite a hazard, and it
also created a heck of a voltage drop to our NST bank. :)

6 - 15Kv/30mA NST's paralleled for 180mA

120v in, 0-145v out, 1.4KVA Powerstat variac.  (Very nice variac, don't
wanna blow it up, and a 1.4KVA variac very obviously is not going to handle
a 10KVA pig. :-)

80Amp RF Filter

We are using 10-gauge copper housewire for the Tesla primary circuit
connections.  This is all we can really afford in bulk.  (Because my
partner's dad is part electrician and wires houses :-)   It would be nice
to buy a 100' roll of welding cable, and 20 solid copper ring terminals,
but that's not too feasible right now.  The wire we are using does not have
very good insulation, but you can still grab the wire with your bare hands
and draw arcs.  I think the 10ga copper is rated for 30amps.  It's
housewire.  Nevertheless, with 120v, I reckon it'll take some 84amps to
create 10KVA of power.  I have a feeling that it won't be easy to find
equipment to handle 84 amps, although wiring a new, dedicated circuit from
my breaker box is no problem.

The spark gap is a single static 120psi air-blasted gap with 1/4" solid
brass bolts as electrodes.  It works wonderfully for our NST power, and
replacing the old steel bolts with the brass actually added over a foot of
arclength to our Tesla coil.  Still, I have a bad feeling that 10KVA will
tear the poor spark gap to shreds, and it will be very inefficient for the
while that it lasts.  But, if you do feel that this spark gap is adequate,
it would make me very happy to stick with it, because I don't know if we
have the knowledge, and certainly not the materials, to build a rotary gap.
 We do, on the other hand, happen to have a portable, powerful air
compressor. :)

The capacitors we have are definitely an issue that will need to be
addressed.  We are using an MMC, which consists of two strings of 30 caps
each.  Each cap is .21µf -at- 600vac.  That would mean that the entire system
is .014µf -at- 18000VAC.  Now, not only are the capacitors strewn about in an
unsightly manner instead of neatly soldered on a breadboard (how was I to
find a board so big as to put 60 caps on it?), but the calculated primary
capacitance is about .02µf, and the matched capacitance for the NST bank is
closer to .03µf.   High voltage caps are just too hard to come by for us. 
They certainly don't sell any in town (I live in the middle of nowhere, in
the wastelands of Texas), and any that might appear on eBay quickly jump
above the $100 mark.

The primary is 16 turns of 1/4" copper tubing, with 1/4" spacing between
turns.  No big concerns here, but remember the 10ga housewire we using for
connections.  Our primary tap connection is weak to say the least. (A ring
terminal)

The secondary is wound on 8" PVC (9" outside diameter).  It is 21ga magnet
wire, and the winding is 32" tall.  I'm worried that 21ga wire might also
be too small to handle the 10KVA pig.  The secondary is grounded to a 6
foot copper pipe that I drove all the way into the earth, pulled back out,
filled the hole with salt, then drove the pipe back in.  The grounding
cable is a piece of (galvanized alluminum?) real power-line that we got
from a local electrical contractor.
-----------

Anyway, I am pretty confident that I am going to buy this distribution
transformer, even if we have to spend more months building a new Tesla coil
around it.  I thank you very much for your time, and I would be incredibly
happy to get any advice you can give me about upgrading my system to
accomodate the extra power, especially in the areas of ballasting the pig,
and finding equipment to handle the potential 84 amps that the pig will
draw.

	Thanks,
	   Ryan Ries