Re: Black ABS

["Tesla list" <tesla@xxxxxxxxxx>]

Original poster: "Jon Danniken" <danniken@xxxxxxxxxxx>

> Original poster: "Chris Farmer"
> Jon,
> I am building my first coil and I have the same source 15kV 60mA NST
> could you tell me the basic design of yours and the performace you
> actually get from it?

Hi Chris,

I made the primary and secondary about 10 years ago, and used it with glass
caps and a static gap. Last year I upgraded it with a larger top (4.5" x 23"
toroid), an MMC cap (0.025uF), and a 120BPS rotary (lexan rotor, 1/8"
diameter tungsten rod set in 3/8" threaded rod holders). The way it is now,
I get occasional bluish white 36" strikes to a 4 inch diameter foil covered
sphere.

It should probably be capable of more, but at the time I didn't know as much
as I know now, and only wound the secondary to 20.5" (diameter is 4.5", with
1066 winds of 25AWG). With the inverted conical primary, I get racing sparks
like crazy unless I back way off on the coupling. In hindsight, a flat
primary and a winding length of 22.5" might have improved performance by
allowing me to couple it a little tighter and more uniformly, as well as
giving me more turns.

I think it would probably also benefit from a 6" secondary coilform and a
flat primary, which I considered at one point, but my efforts are going into
my next coil system instead of further upgrading this one.

Here's a picture of it as it is now:
http://teslacoils.home.comcast.net/4.5Tesla.jpg

Jon