Fw: Primary to primary sparking?

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

Original poster: "John Richardson" <jprich-at-up-dot-net> 

Hi Chris,

I looked at your picture again, and it appears that you are using wire
staples to hold your primary directly against your wooden base.  If you are
in a damp climate, or your base is painted with something even remotely
conductive, this could also cause some issues.  Just another thought.

John Richardson


 > Hi Chris,
 >
 > I've got a few thoughts, which may or may not help.  I am going to guess
 > that you are tapping at a relatively small number of turns, and that your
 > turn to turn spacing is on the small side, say under a 1/4 inch.  I've
found
 > this to be a big mistake.  Try to keep turn spacing 3/8 or better.  It
seems
 > at higher power levels, when tapped at low turn numbers, that the easiest
 > path for energy dissipation can sometimes be the next turn as opposed to
the
 > secondary.  This will especially be pronounced if you are out of tune,
which
 > the lack of streamers leads me to believe.  Are you sure that your tapping
 > mechanism isn't coming within a hair's width of the adjacent turn?  This
 > will also cause your problem.  BTW, what is your power source, and what
type
 > of gap are you using?  All I can make out from the picture is a glowing
UFO
 > type of deal, and I'm thinking it's a TCBOR style gap.
 >
 > John Richardson

 >
 >
 > > Original poster: Chris Roberts <quezacotl_14000000000000-at-yahoo-dot-com>
 > >
 > >
 > > Hi everyone,
 > >
 > > I just got the coil out to do some pictures, along with trying it out
 > > without a breakout point at the top. It seems to not like that, seeing
as
 > > it had plenty of racing sparks, primary to secondary flashovers, and
other
 > > problems. I guess it is a result of a higher breakout voltage? Anyways,
 > > during one of these pictures, the coil flashed brightly with a huge mean
 > > sounding spark. I shut it down and took a look. The spark seemed to
occur
 > > between the primary tap and the next outside winding, seeing as that's
 > > where the scorch marks are. So why would the coil want to do that?
 > > Shouldn't the tap and the primary be at the same polarity? Even if they
 > > were, wouldn't it be easier to have the current go around one more turn
 > > instead of blasting through the air? Whenever I fix this thing from
 > > sparking in one spot it starts in another... except for all off the top.
 > Is
 > > that so hard for it to do? Oh well, it at least made the ! photo look
that
 > > much better! =D
 > >
 > >
 >
<http://hot-streamer-dot-com/temp/P1010077.JPG>http://hot-streamer-dot-com/temp/P101
 > 0077.JPG
 > >
 > >
 > > -Chris
 > >
 > >
 > >
 >