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RE: Run Failure, need help

	I had an idea that it may be the coupling, but I being lazy just put on 2
coats of polyurethane ( I would have to disassemble everything to raise the
coil).  I tried the coil again on 5/4, and I got a few large bursts from a
few places in the secondary coil.  I tested it, an it still has continuity
so I figure it is still OK?  Unfortunately I thing I blew the transformer
somehow.  After increasing the main gap distance the safety gap fired a few
times, then the whole thing stopped.  Suspecting the transformer I 'tested'
it by creating an arc from each HV output to the case, and they both worked.
I suspect I will try a few different transformers.  I should have mentioned
before that the transformer is a 15000 v 30ma NST.  One small flaw that I
found was that my beer bottle capacitor was rated for .009 uf rather than
.005!  I based it on an idea I saw in a book, which rated each bottle at
.0005 uf, so I used ten.  Today I tested it with a capacitance meter, and I
found the error.  Could that also have contributed to the failure?  One more
question- for the ground I am using a 14 awg cable attached to a steel or
iron rod, about 4ft in the earth.  Is that sufficient?  Thank You,

-Andy

> -----Original Message-----
> From: Tesla List [mailto:tesla-at-pupman-dot-com]
> Sent: Tuesday, May 04, 1999 6:24 AM
> To: tesla-at-pupman-dot-com
> Subject: RE: Run Failure, need help
>
>
> Original Poster: Gary Lau  03-May-1999 2033 <lau-at-hdecad.ENET.dec-dot-com>
>
> >Original Poster: "Andy Cleary" <gemware2-at-dreamscape-dot-com>
> >
> >	Today, Sunday 5/2 I tried out my coil for the first time.
> First what
> >happened is I put the secondary coils ground wire and the primary coils
> >power wire through the same hole in the base, and that was a big
> problem!  I
> >got smoke, burning, etc.  After that I made a different hole, and brought
> >the first primary coil turn further from the secondary and cured that
> >problem.  The problem that I have now is major arcing up and down the
> >secondary coil.  I suspect that it is due to the poor surplus wire that I
> >have been warned about.  If that is the case then I will apply a
> few liberal
> >coats of polyurethane with a brush.  Would it possibly be a coupling
> >problem?  Would it help If I raised the coil up a notch?  Thank
> you for the
> >help in that area.  now for more general questions.  What widths should I
> >start the spark gap and safety gap at?  The safety gap does not
> fire at all,
> >and the static gap fires very often, almost continual.  Another
> question I
> >have deals with the moveable tap.  When I tried putting it in both in the
> >middle and the outside, nothing works.  No arcing, no sparks in the gap,
> >etc.  I am very excited, though, because I think that it is
> working fairly
> >well for a first run.  Thank you for the help,
> >
> >-Andy Cleary
>
> If there is arcing up and down the secondary, stop right away before you
> permanently damage it, and raise your secondary up higher to reduce the
> coupling.  That's the problem, not your wire.
>
> The main gap is supposed to fire continuously.  If it ever stops firing,
> even just briefly, it means one of two things.  Either you've toasted
> your NST, or that you are about to because your main gap is too wide.
> You didn't say what voltage your transformer was so I can't comment on
> what a proper gap setting is.  With my 15KV NST, I use a 0.36" wide gap,
> but that may be pushing it.  I'd suggest less, especially if you are
> using a lower voltage transformer and a less than bulletproof cap.
>
> The safety gaps should be adjusted so that with the primary tap and main
> gap NOT CONNECTED (very important), the spacing is just below the point
> of arcing, typically about 0.25" on each side for a center-tapped
> transformer.  Also, the safety gap electrodes must be rounded and blunt
> surfaces, preferably small spheres or round carriage bolt heads, not just
> bits of wire.
>
> Regards, Gary Lau
> Waltham, MA USA
>
>