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Re: Jefferson electric NST unpotted - now what?

Hi John.  I run my unpotted neons 'dry'.  I gave them three thick coats
of minwax satin polyurethane while I had the coils and lamination
sections disassembled,  then I reassembled the unit and gave it three
more thick coats of poly.  As for the fine secondary wire, I very
carefully scrapped the enamel off the wire with an x-acto knife while
holding the wire carefully on a little block of pine wood, I did this
while I had the secondaries removed from the laminations.  I then wrapped
the cleaned wire around a piece of stripped and tinned piece of solid #18
copper wire which was about 3" long.  After soldering the joint, I
carefully wrapped the outer wall of the secondary with 'varnished cambric
tape' to hold the secondary lead down onto the coil top.  I then bent the
18ga lead wire at a 90 degree angle so that it pointed straight up off
the secondary.  I then wrapped more tape around the coil to secure the
18ga wire securely.  Then I rechecked the coil with my vom to be sure the
splice was good.  Then I soldered a piece of 18ga. copper stranded
silicon 40kv wire to the 18ga solid wire stub that was sticking out of
the coil.  I then soldered the two 18 ga. wires together and laid them
down carefully atop the top of the coil and continued wrapping with
cambric tape.  I then applied several turns of fiberglass tape to this
and checked it for continuity once more and then polyed the heck out of
it.  Then I gave it several more turns or cambric tape and polyed it some
more.  The cambric tape, which is similar to the actual tape on the
original neon cores is available from the local electrical distributor,
and maybe from some mail order companies.  You could also use masking
tape if you varnish it very well.  Whew, what a job!  Ok, now I got two
insulators(porcelain) and epoxied one to the outside end of each
lamination assembly near the secondary windings and attached the 40kv
silicon wires into these terminals with machine bolts. I held the
pocelains to the lamination end with big gumbands until the epoxy set up.
 I then filled up the entry holes in the porcelains with 5 minute epoxy
and slathered this epoxy all over the terminals and the laminations, the
more the merrier!    After it set I gave the assembly three more thick
coats of polyurethane.  After several days I fired up the tranny and it
worked great!  Yours will too!    Al..    

On Sat, 09 Sep 2000 12:45:36 -0600 "Tesla list" <tesla-at-pupman-dot-com>
> Original poster: "John Morawa" <morawaj-at-interaccess-dot-com> 
> Help!
> I have just finished unpotting an old Jefferson electric 15/30 NST.  
> I
> removed most of the tar via a hammer and various sized chisels.  I 
> then
> submerged the core in a bath of mineral spirits and rubbed her down 
> with
> a paint brush.  Then I did a second bath in lacquer thinner with a
> brush.  It's all cleaned up now.  I then check from the case to the 
> end
> of each secondary.  I get around 10k ohms per side, if I remember
> correctly.  Yahoo!  Now the questions.  I would like to run this guy 
> dry
> (not repot it in anything).  What can anyone recommend as a method 
> to
> reattach HV wires to those oh so super thin secondary wires.  Use
> silicon rubber or hot glue to attach the wire itself to the core and
> just wrap a few turns of the secondary wire around it?  Also, I 
> assume
> the secondary wire is enamel coated.  How do you remove this 
> insulation
> without tearing up the super thin wire so I can solder these wires 
> to
> the HV wires?
> Thanks a bunch,
> John M.