I've used 7 tubes and 0.030 spacing as I recall. I set up an arrangement
so I could vary the number of gaps from 1 to 6 by clamping the wire on the
different tubing. I set the spacing using a feeler gauge, but that's
because I had one. I believe one of the important things too was to make
sure that the tubes are parallel as much as possible, but this is
something done by hand and the tubes were held down by wooden fingers, as
opposed to something done in a machine shop.
On Wed, 3 Jun 2015, Doug wrote:
Where can I find data on spark gap distance for copper tube spark gap, also
number of tubes for given size Tesla coil?