My First Tesla Coil

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

Original poster: "Chris Fanjoy" <zappyman-at-hotmail-dot-com> 

   I've wanted to build one of these for several years now, but just never 
got around to it. But finally, I'm now ready to build my first coil! 
Although I have spent years in electronics (mostly repairing TV's etc), the 
principles involved in Tesla coils are still not completely within my 
grasp. That's why I'm asking for your help.
   I received the main ingredient in the mail today - a 10 lb spool of #27 
AWG magnet wire. Upon seeing the immense size of the spool, I now realize 
that I have more wire than I'll probably ever need! Not a problem though, 
since an associate of mine also wishes to build a coil, and I'll probably 
just share some with him. As for the other materials - high voltage 
transformers, capacitors, large-diameter copper wire, etc - I have a large 
stock of these items that I've collected, from the years I've spent 
repairing consumer electronics.
   I've got quite a mouthful of questions, but I'll try to summarize them 
as briefly as possible:

Consideration #1 : Number of coil turns / turns ratio

   Most info I've collected from the web, suggests winding about 2-4 
thousand turns of 20-24 AWG magnet wire, for the secondary of the coil. The 
primary should be about 20-25 turns of heavier (<14 AWG) copper wire. Is it 
theoretically possible, to use a turns radio of 1:100 (say, primary=10 
turns and secondary =1000 turns), to multiply the input voltage by 100x? 
(assuming 100% efficiency, obviously it will be much lower in real life). 
Secondly, how does one determine the proper number of turns? And finally, 
can the primary and secondary windings be isolated from each other by 
putting a larger-diameter piece of PVC pipe between them? (to prevent arcing)

Consideration #2 : High Voltage Transformer

   Since I have literally dozens of old MOT's in my parts pile, it goes 
without saying that this will be what I use. My first question is, are the 
older (bigger) ones better? Size might be a consideration depending on the 
enclosure I built this stuff into. And also, is it possible to use two 
transformers (primaries wired in parallel, secondaries in series) in order 
to get twice as much voltage to feed to the spark gap/capacitor? Since two 
MOT's would draw more than 15 amps from the wall, some kind of current 
limiting would be needed (custom-wound inductor?)

Consideration #3 : Tank Capacitor

   It seems that everyone uses a tank cap comprised of dozens, or hundreds, 
of small HV caps to get the required value and voltage. I have a fair 
number of mylar caps (mostly from 70's and 80's color TV's) which may do 
the job, but I'm wondering if microwave oven capacitors would work. I have 
dozens of em', and most have values of 0.7 - 1.0 uF at up to 2400VAC - 
each! Only thing is, they have bleeder resistors (typically 10meg-ohms 
each) and might not withstand high operationg frequencies. And what about 
high-voltage ceramic capacitors, are these any good?

   Maybe that's enough questions for now. It will take some time to 
assemble all the components, and work out the design. I look forward to any 
advice you may have.