Re: tungsten electrodes

["Barton B. Anderson" <tesla123-at-pacbell-dot-net> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Hi John M., 

I had to reply after taking a peak at the tungsten sight you posted. 
 From the 4 types listed, Pure tungsten is rated the best arc stability at AC.
Obviously, these are for welding electrode applications and probably could be
used in an RSG application. My RSG uses pure tungsten 0.375" diam. They are
fantastic! With most other metals, there is some amount of contamination,
pitting, etc., but pure tungsten will out last them all. It's pricey however. I
would recommend at least 1/4" diameter. My reasoning for this is if you round
the tips, the radius of curvature becomes effective in the gap (they will last
longer as well). You will probably get a better price simply buying a length of
rod stock from McMaster-Carr, MSC Industrial Supply, or the like. The
stationary's will get hot of course, but mounting them in a mass of brass will
dissipate the heat to keep them cool. I use brass blocks for my stationary
standoffs. 

Bart 

Tesla list wrote: 
>
> Original poster: John_Morawa-at-em.fcnbd-dot-com 
>
> Hey Terry and John, 
>
> I don't remember asking either of you what the material of your RSG 
> electrodes is.  Do you use tungsten?  if you take a peek at this site; 
> www.arcsmith-dot-com/wni/products/tungsten/tungsten.htm     they give some 
> interesting descriptions/characteristics of some of the different types 
> of tungsten.  Have you ever tried any of these or know which is most 
> sought after for use in RSG's?  Also, what diameter would you recomend 
> if running 450 - 900VA through them and would you recomend a larger 
> diameter on the stationary electrodes to dissapate heat better since 
> each of the stationaries arcs X times more than any single electrode on 
> a disk with X number of disk electrodes. 
>
> Thanks much, 
> John M.