intro + coil questions

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: Ben Buxton <bb@xxxxxxxxxx>


I've just joined this list and thought I'd introduce myself before 
asking a question or 2 on coil design.

I hail from Sydney, Australia and have been interested in electronics 
for a long time now. I've played a lot with high voltage stuff as 
well, having done things involving he-ne lasers, ignition coils, 
LOPTs and jacobs ladders from NSTs. Getting good HV gear is 
reasonably easy here so there's plenty of room to play.

My most ambitious project is, naturally, a Tesla coil. I'm currently 
building a 6" coil, powered from a 15kv, 60mA NST. I've sourced all 
the parts (including TDK pulse capacitors) and am slowly getting it 
all assembled.

One aspect I've not yet found an answer to is whether to place the 
NST across the gap or the caps. Some designs have it one way, and 
others the other. Is there any guideline as to what's best? I can see 
things involving less kickback to the NST with it across the gap, but 
there's probably more to it than that.

I've also got a bit of a concern with my secondary. As I'd not been 
able to (read - didnt research hard enough!) find long enough single 
spools of wire to wind with, I've used 3 x 250metre spools, and made 
splices along the length. These consist of the ends soldered together 
(with minimal 'sharpness') and sleeving places over the join, then 
epoxy sealed using araldite. Will this give me any problems? After 
winding, I only now know where i could find 700 metre spools, but too late!

Thanks for any help!

Ben