RE: easy tungsten source?

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

Original poster: "Ted Rosenberg by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Ted.Rosenberg-at-radioshack-dot-com>

Bert, all:
I'd appreciate a hunch/guess comment if you would on the following:
A friend of mine manages a wire hanger factory. In the manufacturing
process, steel is drawn thinner and thinner by a series of tungsten carbide
dies that look like donuts.
I bought 9 of these in a suitable size...they are slightly larger than the
size of a Life Saver. I will mount them using 1/4-20 brass bolts so they are
lollypop like, one next to the other.
This is to replace my 9 copper sweat couplers which get oxidized badly every
two-three hours of use at Hangmans House.

The donuts appear gray, matte finish.

Any ideas?

And if the arrangement works as planned, I will tell everyone and I am sure
that my frien can get more. But they tend to be pricey, about $8 each.

Safety First

Ted
=====================================================
Subject: Re: easy tungsten source?

Original poster: "Bert Hickman by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<bert.hickman-at-aquila-dot-net>

All,

One other potential problem is that, as with so-called tungsten darts,
they are most likely a tungsten-nickel alloy containing 10-30% nickel
since pure tungsten tends to too brittle for most common applications.
If used in a spark gap some electrode metal is likely to be vaporized or
oxidized in operation, and these byproducts may then be accidentally
inhaled. The Material Safety Data Sheet (MSDS) for nickel lists it as a
possible cancer causing agent (a carcinogen). Similar warnings apply to
chromium, making stainless steel an unattractive electrode option as
well. Nickel's green and black oxides (Nickel II, Nickel III) also have
similar MSDS warnings, along with chromium oxide. They are all
potentially quite nasty compounds that you really DON'T want in your
body. Fortunately, no such warnings apply to pure tungsten or its
oxides.

For further information, check out the following MSDS site referenced by
Ed Wingate in a post last year:
http://www.espi-metals-dot-com/msds.htm

Safe coilin' to you!

-- Bert --


Tesla list wrote:
> 
> Original poster: "Lau, Gary by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<Gary.Lau-at-compaq-dot-com>
> 
> One of the design goals in constructing spark gap electrodes is that
> they should be reasonably thermally massive, so that the heat generated
> at the arcing point is rapidly conducted into the rest of the electrode,
> to keep the arcing point as cool as possible.  Should the arcing point
> become hot, it will quench poorly and arc at a lower voltage (static
> gap) or greater gap separation (RSG) than a properly cooled gap.
> 
> Pen tips are surely very thin and would have a high thermal resistance,
> and the arcing point would become very hot.
> 
> Gary Lau
> MA, USA
> 
> -----Original Message-----
> From: Tesla list [mailto:tesla-at-pupman-dot-com]
> Sent: Saturday, June 09, 2001 11:11 PM
> To: tesla-at-pupman-dot-com
> Subject: easy tungsten source?
> 
> Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
> <RQBauzon-at-aol-dot-com>
> 
> isnt tungsten used  for some pen tips? if so, would it be possible to
> use pen
> tips for a spark gap?