Re: More Capacitor Ideas

Subject:   Re: More Capacitor Ideas
  Date:    Wed, 2 Jan 1980 13:16:50 +0500
  From:    "Alfred A. Skrocki" <alfred.skrocki-at-cybernetworking-dot-com>
    To:    Tesla List <tesla-at-pupman-dot-com>

On Thu, 12 Jun 1997 14:10:20 -0400 Thomas McGahee
<tom_mcgahee-at-sigmais-dot-com> wrote;

> Some more thoughts:
> I am sure that most of the ideas I come up with have also been
> thought about by others like Malcolm Watts and Alfred Skrocki and
> Mike Hammer, just to mention a few. Mike even asked me if I had been
> spying on him :) Nope. I gues that it's just that great minds often
> think along the same lines. Different actual thoughts, but remarkably
> similar in many respects. When I get a really good idea I like to
> work out all the details, verify it, and then share it. Sometimes I
> don't have the time to do the actual full-scale build-it part before
> I find it adviseable to begin sharing the thought part. Like many of
> you, I am a sort of hands-on experimenter type and I love to actually
> try out my ideas. I have done *enough* initial experimentation on
> this idea to know that it has an excellent chance of taking care of
> one of our biggest problems with capacitors: the stupid stinking air
> bubbles.

I have found that sometimes it is an "ideas time" and many people
experimenting with similar goals will all come up with that same 
idea! Examples in point would be the light bulb and the telephone.

> I am fairly confident that if originally assembled in a container
> under oil, that the assembled unit could then be lifted out and
> transferred to a smaller container without much chance of air getting
> back inside the assembly. In its new home it should ALSO be
> oil-immersed. This is important to make sure that we don't get
> corona/sparks around the edges of the poly, which is protected only
> by the oil.

Once the capacitor is clamped under pressure, I have no doubt that it 
could successfully be removed from the oil and transported elsewhere 
then have it's oil returned. It would work because once under 
pressure the plates would be sufficiently close together that 
capillary attraction would keep the oil between the plates.

A point in regards to sparks around the edges of polyethylene or
any other dielectric. I am sure we are all aware of the effect of
having both D.C. and A.C. sparks that are much longer going over the 
edge of a dielectric than they will in free space. I am sure this is
just as true in a liquid atmosphere (under oil) as it is in a 
gaseous atmosphere like air, a bit of experimentation might be called 
for to be sure of a "safe" edge spacing under a given oil.

> *****
> Thinking Even Bigger Thoughts...
> Hmmmm. Thinking about it, *IF* the extra poly around the edges (all
> four edges) were made about an inch larger than normal, and if the
> assembly was assembled under oil or at least with a brushing of oil
> on *ALL* surfaces (even poly-to-poly surfaces) and really bolted down
> super-tight you *might* be able to get by without needing continued
> oil immersion. But it seems a bit too risky for me.

I think in principle your correct and it would be good to have the 
oil as an added security and perhaps the amount of oil space 
surrounding the capacitor could be reduced. There is no need to have 
say a capacitor that's a six inch cube in an eight inch cube filled 
with oil! I am sure it would be just as safe in a 6 1/8 inch cube
since all we need to do is have enough oil around the capacitor to 
exclude all the air. This would substantialy reduce the amount of oil
needed and the associated weight as well.

> But I think there is a safer way to accomplish almost the same thing.
> See what you think of THIS idea:
> First assemble the...

Nice idea! My concern is again bubbles! When you lay down the sticky
coated sheets of dielectric or conductor you will again get air 
bubbles in between the parts. It would seem that the only way is 
again to build the capacitor under what ever insulation you are using 
- spar varnish , polyurethane, what ever! This has the advantage of 
not only excluding all bubbles during assembly but eliminates the 
need to rush the assembly since only the surface hardens, and that 
would be a skin on top of the container.

> Hope the thoughts are useful and trigger even bigger and better
> thoughts!

This thread seems to have become a kind of brain storming! Ideas 
triggering ideas, the essence of what the list is for!

While responding I got a flash of my own, how about putting the
capacitor together under a vacuum! I mean build a glove box with
an air tight door on one end and pump it down and then assemble
the capacitor without any air to get in between the plates to begin
with! I don't think we need a hard vacuum to make a difference, but
say down to a few millimeters should be fine. Just clamping the 
capacitor together before returning it to full atmosphere should 
yield a rather good capacitor without any oils, but it would be a 
decided help in the assembly of oil or as Fr. Tom now suggests spar 
varnish impregnated capacitors!


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                           Alfred A. Skrocki
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