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Re: brass or tungsten (fwd)

---------- Forwarded message ----------
Date: Sun, 08 Jul 2007 18:16:31 -0700
From: Frank <fxrays@xxxxxxxxxx>
To: Tesla list <tesla@xxxxxxxxxx>
Subject: Re: brass or tungsten (fwd)

Brass will work if you use induction coils or static machines but 
using NST's (higher currents)  the brass tends to vaporize on the arc 
face and then tarnish. The gap works for a while and then it starts 
to sputter and you have to file the faces to remove the pitting.

Tungsten is far superior but it is hard to work with and expensive as 
you indicated.

A good alternative is zinc! This was a popular arc electrode in 1-5 
KW spark transmitters. It is cheap and easy to thread and cut.

You can find large cast zinc rods from pluming shops, they are in 
water heaters. If you are near a lake or the ocean (much better) you 
can find zinc anodes of various sizes for the engines and heat 
exchangers. Do a quick search and you will find 1/4" zinc rod by the 
length and cheap. Cut with a hacksaw, thread if needed and you have 
electrodes! I think zinc is even cheaper than brass.

If you want to make a zinc disc, go to an art supply place, 
especially on a college campus, and you can buy zinc plate. Artists 
use it for print making.
I still have some 2 ft square sheets of the stuff that is 1/16" thick 
for various projects.


At 06:44 PM 7/8/2007 -0600, you wrote:

>---------- Forwarded message ----------
>Date: Sun, 08 Jul 2007 20:28:00 -0400
>From: Scott Bogard <teslas-intern@xxxxxxxxxxx>
>To: tesla@xxxxxxxxxx
>Subject: brass or tungsten
>Hey everybody,
>      A quick question, would I be better off using a tungsten rod or a brass
>rod in a propeller rotary gap?  my thinking is that tungsten would be able
>to withstand the heat better, but it is expensive and fussy to work with,
>and brass would conduct better and be cheaper, and I could get it in a
>bigger diameter (making it last longer because of improved heat
>dissipation).  When it wears out, I can just move the stationary electrodes
>in to compensate.  I'm just looking for other opinions, and maybe if
>somebody has done some experiments, that would be cool.  Thanks a bunch.
>Scott Bogard.