Background info: I'm trying to create a spark gap tesla coil that uses a ZVS / flyback combo, and so far, given the initial tests with a 12 volt 20 amp power supply, I managed to get it to work, but when I increase the gap between the spark gap, the sparks went through the secondary coil, which could signify that the primary/secondary is too coupled. Note that the primary coil design I used before I took it down is a vertical type.
So I thought after looking at the designs, I should either go with a flat or pancake coil design for the primary, but which one of the 2 suits them best or should I go back to using the vertical type again? I hope I get much powerful sparks for such a small-medium sized coil!
Here is what my tesla coil looks like, note the stick is supposed to be where the primary coil is supposed to be: