Re: strength of vacuum

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Jim Lux" <jimlux-at-earthlink-dot-net> 

Depending on the size, you don't need anything near 1/2".  If you're using
oil for insulation, you don't need inches and inches of it surrounding the
coil, do you?  The primary breakdown path will be through the air on the
outside of the tank.  A half inch or inch of oil around the windings should
be sufficient, and won't weigh much.

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Saturday, November 01, 2003 1:49 PM
Subject: Re: strength of vacuum


 > Original poster: "RIAA/MPAA's Worst Nightmare" <mike.marcum-at-zoomtown-dot-com>
 >
 > Actually I was planning on encasing the secondary in acrylic tubes with
1/2"
 > walls and sealed with cyanoacrylate glue (actually solvent welds the
 > acrylic) with the topload sticking out the top.
 >
 > ----- Original Message -----
 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > To: <tesla-at-pupman-dot-com>
 > Sent: Saturday, November 01, 2003 2:38 PM
 > Subject: Re: strength of vacuum
 >
 >
 >  > Original poster: Yurtle Turtle <yurtle_t-at-yahoo-dot-com>
 >  >
 >  > Of course, what good's running a Tesla coil inside a
 >  > solid steel vessel?
 >  >
 >  > "I know you can't see inside, but trust me, it's
 >  > sparkin' like mad!!!"
 >  >
 >  > Adam
 >  >
 >  >
 >  > --- Tesla list <tesla-at-pupman-dot-com> wrote:
 >  >  > Original poster: Jim Lux <jimlux-at-earthlink-dot-net>
 >  >  >
 >  >  > At 02:35 PM 10/31/2003 -0700, you wrote:
 >  >  > >Original poster: "Dr. Resonance"
 >  >  > <resonance-at-jvlnet-dot-com>
 >  >  > >
 >  >  > >The size of enclosure for TC parts in large high
 >  >  > vacu. would have so much
 >  >  > >surface area that the 15 PSI would probably crush
 >  >  > it.
 >  >  >
 >  >  > Nothing that a competent boiler manufacturer
 >  >  > couldn't make.  Big round
 >  >  > tanks with hemispherical ends can be easily
 >  >  > fabricated and will easily hold
 >  >  > vacuum.  The load's not all that high..  Say you
 >  >  > wanted a 6 foot diameter
 >  >  > chamber.  The hoop load would be 72 * 15 pounds per
 >  >  > linear inch of
 >  >  > chamber.. call it 1500 pounds.  If the chamber walls
 >  >  > were, say, 1/8" thick,
 >  >  > the stress would be 1500*8 psi, or 12000 psi, well
 >  >  > under the yield for
 >  >  > aluminum or steel.
 >  >  >   Naturally, you'd want a bit more sophisticated
 >  >  > design to account for
 >  >  > asymmetrical loads, etc.
 >  >  >
 >  >  > A bigger problem would be the surface finish and the
 >  >  > outgassing.  Large
 >  >  > chambers take a very long time to pump down (or a
 >  >  > very big/fast pump)
 >  >  > because of the large surface area.  I don't have my
 >  >  > Kurt J. Lesker catalog
 >  >  > handy here, but there's some rule of thumb about
 >  >  > outgassing rates per
 >  >  > square cm of area.
 >  >  >
 >  >  >
 >  >
 >  >
 >
 >