RE: Copper pipe spark gap variant

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Vanderputten, Gary by way of Terry Fritz <twftesla-at-qwest-dot-net>" <gvp-at-pvaintl-dot-com>

Last night I made copper pipe gap for a small coil by taking a 2" wide
plastic pill bottle and surrounding it with eight two inch long,   3/4 "
pipe sections. I glued them on  by putting a small bead of epoxy on each
pipe, keeping it neat and 1/2 " away from the ends. You hold everything
in place with a large rubber band which compresses the pipes into each
other. Then spacers made up of four or five layers of sliced up business
cards (that's about .025") are inserted between the pipes at the top and
bottom of each pipe, being sure not to come in contact with the epoxy.
Let it dry overnight. Remove the spacers. Walla! This entire device will
sit inside a section  6" PVC drain pipe. Cover with the muffin fan. It
works well in my initial tests. I am concerned about the effect of the
heat on the epoxy and pill bottle and will continue to test.

Regards

Garome
 -----Original Message-----
From: 	Tesla list [mailto:tesla-at-pupman-dot-com] 
Sent:	Monday, May 21, 2001 7:54 AM
To:	tesla-at-pupman-dot-com
Subject:	Copper pipe spark gap variant

Original poster: "Pete Komen by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<pkomen-at-zianet-dot-com>

I wondered if double-stick foam tape could be used both to hold the
copper
pipe (3/4 inch) down and to separate the pieces of copper pipe.  I tried
it
and the gaps are about 40-45 thousandths.  This seems too wide.  My 12kv
XFMR only jumped 5 gaps.  I had to try it twice.  The first time, the
pipes
had little ridges from the pipe cutter and the arcs liked those spots
and
stayed there.  Tested across the NST only.  I cut a lengthwise piece out
of
a 4" PVC pipe and put the copper pipes across the opening and mounted a
fan
on the end.  Blowing into the 4" pipe caused the power arcs to run down
to
one end and burn the foam tape; the fan swirled the air.  Turning the
fan
around for suction worked much better.  Anyhow, I am still going to use
the
foam tape to hold the copper pipes but I'm looking for a 20-25
thousandths
spacer material.

Has anyone tried a SRSG using an insulating disk with holes or slots cut
in
it to allow electrodes mounted on each side (very close) to arc across?
A
friend of mine suggested it and I may try it in the future.  Is this
feasible?

I got some of the brass balls from
http://www.grandbrass-dot-com/catalog.html
(order by phone) and they are solid brass.  The center hole is bored
nearly
through but I don't think it's a problem.  The 1 1/8" balls I got have
some
pipe thread but they sell adapters.  I'll let y'all know how they work
in a
spark gap when I get it going.  The cost is reasonable if you get the 10
or
more price.

Regards,

Pete