Original poster: "Nightmare" <nightmare-at-bak.rr-dot-com> Hi, this is ravi, i am trying to make a small coil from a 3" x18" pipe for sec., 7.5kV 29mA NST, salt water caps, two 1" pipes for s. gap., and 1/4" copper tubing for the primary, could someone tell me how many turns i should make the primary? like what would be good? thanks