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Re: making copper spheres



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At 09:16 AM 3/9/97 -0600, you wrote:
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>To: tesla-at-pupman-dot-com
>Subject: making copper spheres
>
>Does anyone have a good system for neatly fabricating thin (20-30 gauge)
>copper spheres, say 3" to 6" diameter, as used in Tesla's spherical caps?
>Likewise for the pancake coils (transformers). Yes, I know they are not
>always used or needed. These are particular to the needs of my present
>experiments.
>
>Thanks readers for any assistance.
>
>Peter M. Nielsen, E.E.
>
>
>
>Peter,

I just purchased and received a 12" diametrer pure copper hollow ball from
the   McMasters catalog.

I was charged $144.00 for the ball plus shipping.  I use the ball as an
isoropic capacitance in an E.S. receiver setup.  The Mc Master Catalog, I
believe offers these balls in all sizes up to 12".  I'll try and get back to
you with more data. I believe the balls are the heavier 20 gauge metal.
Mine had a few small dings in it but once polished and over coated with
polyurethane will serve very well.  Inward dents are of no real concern on
such items other than cosmetic.

Richard Hull, TCBOR






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