Re: Tungsten electrodes

From: 	D.C. Cox[SMTP:DR.RESONANCE-at-next-wave-dot-net]
Sent: 	Saturday, December 13, 1997 2:32 AM
To: 	Tesla List
Subject: 	Re: Tungsten electrodes

to: Gary L.

We use 1/2 dia brass with "screw-in" tungsten electrodes that have a
3/8-16NC thread.  We can supply them if necessary.  We run these at power
levels around 5-25 kva and they work fine.  The 1/8 inch rod can be
obtained at any welding supplier with dia up to 1/4 inch on special order. 
1/8 in and 3/16 in are commonly stocked by large welding supply shops.  We
use a minimum 1/2 inch thick and sometimes 5/8 in thick G-10 rotor with a
standard 3/4 HP motor at 1725 RPM.  Usually 10 electrodes seems to work


> From: 	Gary Lau  12-Dec-1997 1617[SMTP:lau-at-hdecad.ENET.dec-dot-com]
> Sent: 	Friday, December 12, 1997 2:50 PM
> To: 	tesla-at-pupman-dot-com
> Subject: 	Tungsten electrodes
> What sizes are tungsten welding rods available in?  All of the RSG
> electrodes I've seen discussed arc from the tip.  Seems to me that a
> geometry that has it arcing in a line along the side of a rod, similar to
> the tubes in an RQ static gap, would result in a cooler, lower impedance,
> faster quenching arc.  Is tungsten available in something like 1/8" rods?
> Also, can tungsten be silver-soldered?
> I'm envisioning 1/2" long by 1/8" dia rod segments, mounted radially and
> embedded in a .09" G10 disk, stator electrodes opposite side 1, tungsten
> rods silver-soldered to a copper plate heat sink on side 2 and
> electrically connected together on side 2.  Stator electrodes are also
> 1/2" long rods parallel to rotor rods.  Power level is 1-2KW, 1800 RPM.
> Gary Lau
> Waltham, MA USA