Re: Superconducting tesla coil...

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

Original poster: "John Richardson" <jprich-at-up-dot-net> 

Hi Guys,

A couple of thoughts:

1)  I was at my wits end pulling cylinder liners on a big Cummins, and my
welding/gas shop offered to blast 'em with nitrogen for free.  Point is, if
you're friendly with your local supply shop, none of this should be a
problem, and it may cost nothing.  In fact, the last time my weld supplier
was out making a delivery, he saw an old pole pig in a corner and asked what
the heck it was for.  I told him, and promised to show him a small coil
soon, and the big one when it was finished.  He was very interested.  If you
can get someone with connections interested, they may help out, even
offering supplies and things a lay person really shouldn't have in their
possession for FREE!

2)  At a fire call once where there was a rolled CO2 tanker with a hole.
Tree branches in the blast zone were frozen solid, and one jab with a pike
pole shattered them.  Point being:  I think there will be issues where the
components coilers use may not survive the slightest bump without turning
your Tesla coil into a pile of  copper an plastic shards.

John Richardson

----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Friday, October 03, 2003 10:35 PM
Subject: RE: Superconducting tesla coil...


 > Original poster: "David Trimmell" <humanb-at-chaoticuniverse-dot-com>
 >
 > I looked into LN2 for a CryoPump some time ago, and the 45 gal Dewars
 > can easily be rented for $30/month (that includes the LN2!).
 > Unfortunately I have never run across one of those dewars for only $100.
 > Jim, what's your source?
 >
 > Regards,
 >
 > David Trimmell
 >
 > -----Original Message-----
 > From: Tesla list [mailto:tesla-at-pupman-dot-com]
 > Sent: Thursday, October 02, 2003 6:47 PM
 > To: tesla-at-pupman-dot-com
 > Subject: Re: Superconducting tesla coil...
 >
 > Original poster: Jim Lux <jimlux-at-earthlink-dot-net>
 >
 > Having done experiments along these lines, for those contemplating using
 >
 > LN2 and immersing a TC....
 >
 > At 05:55 PM 10/2/2003 -0600, you wrote:
 >  >Original poster: The MCP <ejkeever-at-comcast-dot-net>
 >  >Heck, liquid nitrogen isn't *that* expensive, is it?
 >
 > LN2 == Milk as far as cost goes... $.50/liter... $100 gets you a big
 > GP45
 > dewar (that's 45 gallons, folks)
 >
 >
 >
 >
 >  >  But I'd want to be
 >  >careful that my components have similar thermal expansions. Use
 > something
 >  >with a large theremal expansion coefficient as your winding on
 > something that
 >  >doesn't, and you'll get broken/stretched wire as the wire shortens and
 > tenses
 >  >up.
 >
 > Precisely the problem you'll have... particularly things that are
 > plastic,
 > aren't when cooled to 77K...
 >
 >
 >  >Other than that, you'll have to construct a vessel around the coil to
 > contain
 >  >the LN2.
 >
 > Styrofoam is your friend... Those inexpensive plastic water coolers from
 >
 > Home Depot work quite well to hold LN2.  However, seal up the hole where
 >
 > the spout is at the bottom before filling.. if it starts to leak, you'll
 >
 > never be able to patch it.  Putty or epoxy works fine.
 >
 > I'd try using something like sonotube in a larger sonotube (or 5 gal
 > plastic buckets) with the space between filled with "foam in a can" or
 > expanded vermiculite/perlite
 >
 >
 >
 >  >Reminds of an interesting reference from Ben Bova's Moonwar. They refer
 > to the
 >  >mass driver as using "cryogenic aluminum" magnets rather than
 >  >supercondcucting magnets. When was the book written; The first
 > high-temp
 >  >superconductor was created in the early 80's, right?
 >
 >
 > High power magnets have used LN2 cooling for many years.
 >
 >