Tesladownunder wrote ...

You will not get big sparks from this coil.

You should:
1 Use a copper, not steel primary.
2 Use a gauge of wire that allows around 1000 turns (36G may be too small, I think).
3 Have your gap across the transformer input (rather than capacitor).
4 Make a toroid from airconditioning ducting. Don't mount it as high as you have shown.
5 I'm not sure you understand what a salt water cap is. It is NOT glass plates 12x6 inches.
6 Use a spell checker, punctuation and capitalization. Regard it as practice for life when you have to communicate with people who can write properly (like teachers, employers etc)

TDU

J. Aaron Holmes wrote ...

Putting the toroid too high increases your risk of breakout and corona on the top windings of your secondary (which can ruin it pretty quick!). Putting the toroid too low will, I believe, effectively decouple the top windings of your secondary, making them ineffective and decreasing performance. So there is definitely a "sweet spot", but fortunately that also happens to be the best-looking location (aesthetically speaking) in most cases. For a small table-top coil like you seem to be building, I can't see putting the toroid more than a couple of inches above the secondary. Anything much more or less than this will hurt both the performance and appearance of your coil. After all, a toroid floating one foot over the top of your foot-long secondary will look...well...pretty dumb, IMHO.

Instead, work out a topload and breakout point configuration that encourages sparks to go upward and away from your primary. Perhaps controversially, I expect a sphere would be better for this than a toroid. On larger coils, spheres tend to become impractical for a variety of reasons. For small coils, tape a couple of cheapo metal mixing bowls together, stick a nail on top and call it done. Spheres naturally tend to direct the streamers upward. A breakout point (which will be required unless your sphere is undersized) will virtually guarantee this. I experimented with a variety of toploads on my first coil some years ago. It was 3.5" x 20". In the end, I found I could easily squeeze four-foot-long streamers out of it (more than twice the length of the secondary) by using a near-sphere made from two Ikea stainless mixing bowls. I also experimented quite a bit with coupling. The primary was a helical wound on a plastic bucket, and at one point I had the primary lowered almost halfway into the bucket, putting the top turn of the primary only about 12-15" from the topload. Still, the smoothness of the sphere prevented primary strikes, despite the nearly four-foot-long streamers coming off the top of it.

Have fun!

Cheers,
Aaron, N7OE