Original poster: FutureT@xxxxxxx
In a message dated 3/30/05 11:57:43 AM Eastern Standard Time,
tesla@xxxxxxxxxx writes:
Ben,
The key with a static gap is to get good quenching without too much
loss. The best type and size of static gap depends on the power level.
For your NST you don't need anything too special. But it's not a good
idea to use just a couple of screw heads or something.
One gap that works is the Terry multiple gap which consists of about
20 1/2" copper tubing pieces each 2" long arranged on a piece of
wood or plastic. Use aligator clips to attach your wires. Set the
pipes about 0.008" apart and use as many pipes as needed to get
the best sparks.
Another method that works well is to use larger copper tubes
but use only about 6 of them spaced farther apart. In some
cases it's good to have air blowing on them from a fan.
There's the Gary Lau sucker or pressure vortex gap, but it may
be overkill for your coil.
Then there's the TCBOR gap often mistakenly called the RQ gap.
which has some copper tubes in a piece of PVC pipe with a fan
at the end.
When I use a rotary with such an NST, I use 120 bps synchronous.
Yes, for non-sync rotary operation a higher break rate would be better but
will probably give shorter sparks. The sync rotary can give about
42" sparks with that NST and a good coil design if you apply 140
volts AC to the NST input using a stepup type variac. The static gap
usually gives about 38" maximum. The static gap generally will
not run as smoothly in this application, but is certainly OK.
http://hometown.aol.com/futuret/page3.html
Cheers,
John