RE: Static gap......The Fellowship of the Ringup

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

Original poster: Brett Miller <brmtesla2-at-yahoo-dot-com> 

Luke,

--- Tesla list <tesla-at-pupman-dot-com> wrote:
 > Original poster: "Luke" <Bluu-at-cox-dot-net>
 >
 > Thanx for the input
 >
 > Also when you mention the TCBOR gap that is the same
 > as the RQ gap
 > correct?
 > Ran across some postings talking about where it came
 > from.

Yep.  According to what I've read it was first used
and apparently invented by Richard Hull and the Tesla
Coil Builders of Richmond (Virginia).  Shortly after
this in the the pre TCML computer BBS era, Richard
Quick released a Word Document with pictures and text
describing how to build the cylinder static gap.  It
was a decent document, with accurate measurements and
dimensions -- everything you needed to build the gap.
After this people started calling it the RQ gap, since
it achieved an even greater popularity do to Mr.
Quick.

I personally like to give credit where credit is due,
so I call it a TCBOR.  I noticed other some coilers do
this as well.

 > You mention a gap performing if all the conditions
 > are met.
 > What conditions are those?

I was referring to the phenominon of "quenching" in a
very general sense.  As a scientist (amateur) it is
about as specific as I can really get.  The assumption
is that we want a first notch quench, but in actual
coils it doesn't always provide peak performance for
reasons I don't entirely understand.  Again actual
experimentation and experience is worth a thousand
speculative diatribes.  I should defer you to Richie's
page for more on quenching.  Read all this and look at
the scope waveforms:

http://www.richieburnett.co.uk/operatn2.html#quenching

 > The ones I am thinking of are:
 > 1.	cooling the electrode mass
 > 2.	cooling the air between electrodes
 > 3.	dissipate excess ions in the discharge area

Those are good.  I believe they are all factors which
will improve quenching in your gap system if you give
them consideration.  I would have to argue, again
though...your number 1, 2, and 3 are the same thing.
Also, once you've ran an actual TC for a couple months
you will learn to regognize the failure of one of your
above conditions just by the behavior of the
discharge, and/or the trace on your oscope.

 > And another question
 > There were some posts but I cant seem to find the
 > ones I saw
 > before.......
 > Some say that multiple gaps in series add to gap
 > losses.  Any opinions /
 > tests done on this?

This is directly addressed by Richie Burnett above,
much better than I could do right now.  Make sure you
read the Operation section of the page.

Ok, I just snipped most of my other *lengthy* post,
but if you saved it, you may want to reread the stuff
about my trial of the "Fritz" static gap.

 > In spite of this arcs were much longer with the
 > TCBOR
 > in place tapped for 4 gaps (vs 22 gaps between
 > smaller
 > pipe -- 1/2 inch dia copper in the Fritz gap).

TCBOR with 4 rather large gaps in series (at least 1/8
inch each, but I need to measure with a caliper)

results -- 45 inch arcs and streamers

Fritz gap with 22 very small gaps:  about 30 inch
sparks.

***disclaimer*** The wood base in the Fritz gap was so
damp and lossy that it could have very well caused the
dramatic contrast in performance compared to the
TCBOR.

If anything, this test provided expermental backing
for what I (and I think a few others on here) have
told you about quenching and TC design in general.
What works for one system and environment, might not
be best for another.  Many times you have to just try
it and see.  This gap (22 in series) worked great on
Terry's system, but performed poorly on mine.

Luke, if you want, I can grab a strip of HDPE plastic
and glue the pipes onto that for a real controlled
test that will isolate the moisture loss issue.  Then
we can see how the Fritz gap really performs against a
TCBOR.  Let me know and I'll do it one afternoon this
week.  It would be fun for me, and many could
potentially benefit.  I'll get out the scope and give
you a quenching report too.  I can document it all
with digital pictures.

-Brett