Re: New Coil!
Subject: Re: New Coil!
From: richard.quick-at-slug-dot-org (Richard Quick)
Date: Sat, 7 Oct 1995 04:18:00 GMT
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* Originally By: Lazer-at-netcom-dot-com
* Originally To: Richard Quick
* Originally Re: Re: New Coil!
* Original Area: UUCPE-Mail
* Forwarded by : Blue Wave v2.12
From: Stan Harle <lazer-at-netcom-dot-com>
To: Richard Quick <richard.quick-at-slug-dot-org>
Date: Thu, 5 Oct 1995 22:26:25 -0700 (PDT)
Subject: Re: New Coil!
On Thu, 5 Oct 1995, Richard Quick wrote:
> > 1) How do you effectively cut PVC squarely? I managed, but it was > >
tedious and slow. > > Get a metal strip tape measure. Start with the
factory cut end. Measure > back, then mark all around the circumference.
Score the mark with a > light saw fitted with a metal cutting blade (hack
saw). Once the groove > is scored, cut with a rough cut saw of any
Damn. I was hoping there was some elegant trick that I hadn't
thought of. Most of my shop experience has been with either wood or
metal, and never with tubing.
> > 2) How do you get the primary into a flat spiral? Again, I seem to
> > have managed, but it was a royal pain.
> This one is accomplished with pure time. It is not easy, and neither
> is coil building. Wait until you wrestle a 100 foot length of 1/2 or
> 3/4 inch tubing into a 15 turn flat spiral. It takes not days... but
> weeks or even months before the conductor is "trained".
After fighting with 3/8 inch for several days, and still not
quite finished, but functional, I find this easy to believe. Again, I was
hoping there was a method that I hadn't thought of. Looking over my mail
earlier, I saw that there was a process posted on this. I'll look it over.
Now for the killer question: How'd you make the neat flat coil on your
video? My guess was that you got it roughed in, then ran several drilled
pieces of plexiglass along the windings to form the support. My friend
says that you drilled and split the PVC, then epoxied or hot glued. Who's
> > Initial test of the capacitors indicate that 3 liter coke bottles
> > don't have very much dielectric strength. Wish I'd gotten pictures
> > of the corona.
> I could have (should have?) warned you about this. This material is
> much too thin.
I'm glad you didn't. (g) I've been learning lots, and this was
one more step in the process. Besides, I wouldn't have seen that neat
display. The coil is pretty much done now, with the exception of the
capacitance. I popped four of the coke bottles before I realized what
was happening. Apparently, the "plasma globe" display is the dielectric
and electrolyte breaking down, at least partially. When the coil has had
power applied for a while, One of the arcs either settles, a heat spot
forms, or something along those lines, and the plastic (and cap) fails.
I ended up taking my toroid off, and getting perhaps an inch of
spark from the bare wire. This is probably just the turns ratio rise from
what little energy is making it through the caps. From the severity of
the discharge inside the caps, most of the energy is being dissipated,
not held, in them.
Incidentally, my whole aim has been to sort of "slap together" a
coil, if all this can be called that, and then upgrade components
piecemeal. The gap is presently just a few wide gap statics. This seems
to be barely enough to work, as they seem to
be quenching with three xfrmrs, but not with four. What's a good
method for placing the tubing in the static cylinder gaps? I can't seem
to gauge the holes and thus far have ended up with sort of slots.
My first problem was that the section of tubing that became my gap wasn't cut
straight in the first place. The second is to get the pipe properly
positioned. Then I'll complete the rest of the tube placement.
If I understand the gap function properly though:
> I should be able to get spark as long as the gap is firing and
quenching, at least minimally.
> The main reason for splitting the gap into many segments is to
quench the gap, secondarily for cooling purposes.
> A sign that the static pipe type gaps are quenching is the spark
moving freely in the gap.
Are these correct?
Also, I came up with a pretty decent toroid. I bought about a 10
inch wheelbarrow tire, and stuffed it with newspaper until it was stiff.
Then I wrapped it carefully around the tube with duct tape. I then
placed some thick cardboard into the center, then wrapped the whole
assembly with Al plumber's tape. Came out pretty good, at a total expediture
of about 25 bucks.
You need to look at "tupperware" like thicknesses in your dielectric...
(was that a hint or what?).
Thanks. If I use a large bucket and threaded rod, does the top of
the container _have_ to be covered, or can it be open?
BTW, what did you pay for your capacitors again?
-Duct tape is _not_ a good dielectric!
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