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Jim Horton Jim Horton is offline
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Default spark generator II

Mainly from Rick's kind encouragement regarding using wax for potting, I
picked up a spare pair of HEI coils from the junk yard yesterday. I
decided to pot this pair in the leftover paraffin I had from my recent
potting/ depotting. This time I did not fill completely to the top and
left about an inch of space. Once the wax started to harden and leave a
"well" in the center, I then topped off with some remaining hot wax.
Once completely dried and cooled today, there was still a well, but very
small and of no concern.

There was the capacitor/ resistor series combination I asked about
prior. Still not sure what they are for, I went ahead and added them to
this pair too, but I did it after the wax potting by leaving some target
leads above the wax so the parts could be soldered. After confirming
everything working, I covered and surrounded the RC's with high voltage
tape.

I can only guess about the RC circuit. It was probably something
someone recommended adding to my original circuit. It's purpose might
have been as an interference filter, or maybe to drain the circuit when
off so that one is not shocked from the possible stored charge in the
capacitors.

Anyway, it's working great! The hardest part, and I must have forgotten
about this, was getting solder to stick to the HV output terminals of
the HEI coils! It took my 240 watt iron to do it, and even then it took
a while for the heating to reach optimum.

This paraffin has a melting temperature of 130 F. No additives, easily
melted in a double boiler. I did go with another 6x6x4 junction box
after first trying a similar sized polypropylene dollar store container.
While trying to punch holes in the side for the low voltage primary
leads, the entire container cracked on that side. I tried gluing it
with hot glue, but the moment the wax hit that, it went right through.
Thank goodness for the aluminum tray underneath! With the junction box,
although more expensive, JB Quik Weld has the primary feedthroughs cured
well enough within 2 hours to hold up to wax and oven heat. I did not
bring the HV TV wire leads out the side this time and had them exit at
the top. Seems to work fine with no unwanted arcing. I did not cover
over the top with the junction box cover, just made sure the wax filled
it up.

I also made a solder smoke remover out of a Youtube video I saw using a
plastic container, PC fan, and blue evaporative cooling filter you cut
yourself. You wet the filters, activate the fan and go. It would be
easy to add an activated charcoal layer, but I didn't this time as all I
was working with was standard solder. Seemed to do the job although you
have to be within about 6" with the circuit or iron for it to draw in
the smoke.