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Update


I fired the newly re-wire 25 kVA pig on my 8 inch coil again
tonight. The smoke detectors were disabled, I had some strike
shielding around the wiring, and things were a bit less traumatic
despite the fact I was actually processing more power.

The coil performance was awesome. The increased voltage in the
pig really turned the trick and the sparks grew so long and
fierce I was unable to dial the variacs all the way up without
increased shielding, more room, or both. Six foot strikes were
the norm, with discharges hitting the concrete floor in brilliant
white hot power arcs.

The pig starts out very smooth, but I did feel some unusual
"bumping" in the power cabinet as I raised the voltage up. This
feeling was quite noticeable in the variac wheel and was
acompanied by a 4-5 amp surge on the panel meter. I had the
current limiting set for about 20 amps, so the surges were
substantial. For the first 40% or so of the variac travel the
system runs smooth a silk. As I turned the variac a bit more the
coil grew quite a bit fiercer, and then these unusual bumping
surges would begin. There was no regularity or descernable
pattern. I will investigate this some more, and it may be time to
haul out the oven elements and wire those across the arc welder
inductor to smooth things down as the power levels increase.

Another area that needs attention are the gaps. I galled the
pulley and shaft a bit on my large variable speed rotary, so I
need to tear the guts down and do some work on that. The pulley
was one of these "self balancing" jobs and I don't think it was
built for the high RPMs I subjected it to. It appears to be self-
unbalanced now and the vibration has galled the motor shaft a
bit. I can still run it, but it is too strained to exceed much
over 2000 RPM, so that is scheduled for a rebuild. Lots of little
things to do, but obviously the basics are in place. I am
generally pleased with the rewired pole pig.

Richard Quick



... If all else fails... Throw another megavolt across it!
___ Blue Wave/QWK v2.12