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Santa has been weightlifting!




New Year's Greetings Everyone!

Santa must be working out a lot these days.  I don't know how the heck he
got it down the chimney without waking us all up, but somehow he brought a
nice new 225 amp stick welder for Christmas (yup, my family knows me well
:).   Actually it didn't arrive in time, so on Fri the 27th I drove a
couple of hours to pick it up at the shipping company that had it.  They
couldn't deliver until the next Monday, by which time I would have been
back in NY, and the coil would have been disassembled.  Impatience got the
better of me!  Anyway, immediately upon getting home I went up to the cold
& dark tool shed (brrrr...), wired the welder in series with the main
variac on my 6" coil, removed the old radiant heaters which had provided
ballast previously, set the welder to its lowest setting, turned on the
juice and.......yow!!!  The arcs were incredible!  Continuous bright white
50++ inchers, limited mostly by the space in the shed.  That big inductor
sure gives the coil some kick, however performance was a bit erratic.   I'm
going to add a little resistance next to smooth things out,  and I gather
this has worked well for others here.  I haven't posted stats on this coil
since sometime last summer, so here they are for those interested:

6" diameter plexiglass form wound to 28" with #22 double formvar wire, 9"
dryer duct elbow toroid on a pizza pan, resonant frequency around 188kHz,
1/4" copper tube primary,  2 surplus FCI 100kV DC .01uF caps in parallel
for .02uF, 7 cylinderical gaps blown by a leaf blower, 14.4kV 5kVA
distribution transformer.  No nice carpentry here!  The primary is on top
of a bunch of milk crates, and extensive use is made of wire ties and PVC
pipe scraps.  What can I say.....I'm always changing things anyway.

I have attached a BinHex'd JPEG which I thought you all might all get a
kick out of since it came out pretty well.  A larger version is also on my
web site.  You can see the top of the leaf blower under a mesh screen in
the bottom left of the image.  Yes, that's my custom proprietary, patent
applied for, Ultra Low-Q InstaGap.  ;)  It actually works pretty well,
though a rotary gap is my next priority.  That primary strike rail is new,
and you can see why I needed it!  A larger diameter toroid should reduce
downward strikes.  I've put a Quicktime movie of this coil on my web site,
and there are also some other stills (URL below).  It's quite interesting
stepping through the movie one frame at a time since you can see how the
leaders grow and evolve.  This coil has a way to go before achieving
maximum performance, but it sure is fun adding things incrementally and
watching the sparks grow.

Best wishes to all for an ozone filled '97!

Charles Brush
http://www.foundrygroup-dot-com/cbrush


P.S. Congratulations Chip on the growth of this list!


[ NOTE: The image is coming later tonight to the image sub list -- Chip]