Help with First Coil (was MMC vs. Maxwell caps)

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Bill Vanyo by way of Terry Fritz <twftesla-at-uswest-dot-net>" <vanyo-at-echoes-dot-net>

Tesla list wrote:
> 
> Original poster: "Barton B. Anderson by way of Terry Fritz
?twftesla-at-uswest-dot-net?" ?tesla123-at-pacbell-dot-net?
> 
> Hi Bill,
> 
> Tesla list wrote:
> 
> ? Original poster: "Bill Vanyo by way of Terry Fritz ?twftesla-at-uswest-dot-net?"
> ?vanyo-at-echoes-dot-net?
> ?
> ? I'm building my first coil, somewhat medium size.
> ?
> ? The primary and secondary are done already (secondary is 6.5" by 27.5",
> ? 1000 turns of 22 awg, primary is 19.5 turns of 1/4" copper tubing, 1/2"
> ? spacing on centers, inside diameter 9.5").  Also have NST protection
> ? circuit complete (using plan from Terry).
> 
> One missing component is top terminal type and size. This will affect the
> resonant frequency and
> where you need to tune it at.Your primary at 19.5 turns and .03uF is around
> 66.6kHz. You'd need
> a mighty toroid (much larger than you would allow a spark to emerge) to hit
> that Fr. I like to
> keep the toroid cord (roc size) slightly under or at least at the secondary
> diameter. So say 6"
> x 36" will put the secondary Fr at about 127kHz. The primary can then tune
> at a near tap
> position of 10.6 turns.

OK, let me give the specifics of everything I have, then ask the
questions.  I know I need help getting everything to match properly. 
I've put a lot of work into this so far (as well as having wasted a few
bucks on some bad caps), much to my wifes annoyance, but I'm real happy
with the way the primary and secondary have turned out, so I geuss it's
OK (she won't be reading this).

Secondary: 1000 turns of 22 awg, 6.5" (closer to 6 5/8) diameter, 27.5"
winding length.

Primary: Flat spiral, 19.5 turns of 1/4" copper tube, 1/2" spacing on
centers.  Inside diameter 9.5".  Of course, I expect to tap some way in
from the full 19.5 turns.

Toroid: This I could easily change, but currently, it's 6" alumininum
dryer duct wrapped around an 8" diameter disk (actually two aluminum pie
pans).  This was one of the easier pieces to construct, so I'm amenable
to rebuilding it if necessary.  Have considered a double toroid.

Spark Gap: Not yet finished, but it's a static gap made from 15 copper
tube segments, with an infinitely variable adjustment mechanism, and a
powerful blower for quenching (not a little muffin fan).

Power supply: Two or three 15/60 NST's.

Main Capacitor: MMC, yet to be built (questions about that being posted
seperately).  I want to use an LTR cap to help preserve the NST's, so
I'll use 0.03uF for two 15/60's, or 0.045uF for three.

Miscellaneous: A plexiglass plate covering the primary to prevent
strikes, as well as a strike rail.  RF ground is three 30" copper-clad
steel rods, about 30" apart, driven in ground - best I can do in my
area, though I could add more rods of similar length if necessary. 
Secondary can be raised/lowered about 4" to adjust coupling.  "Standard"
NST protection circuit (
http://hot-streamer-dot-com/TeslaCoils/Misc/NSTFilt.jpg ).  And a 50amp
variac to bring it up slowly (overkill for this, I know).  And finally a
27amp line filter (I have 4 - may put one on the primary side of each
NST) to protect the house.

Q1: Will the toroid I have suffice?  If not, what would be a good size?

Q2: Where, approximately, should the primary be tapped, when using two
15/60's with a 0.03uF cap, and when using three 15/60's with a 0.045uF
cap?

Q3: What sort of spark lengths might I expect with the two and three
NST's, so I'll know when I'm near having it optimally tuned?

All help is greatly appreciated.  When I started playing around with the
idea of doing this, I don't think I really believed I would, but I'd say
it's more than half done now, and I'm looking forward to seeing it run.

	Thanks,
	Bill Vanyo