Spark gap erosion resistance

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

Original poster: "Terry Fritz" <twftesla-at-qwest-dot-net>

Hi All,

While testing my CW coil for Marc, I noticed that the "bullet" inserts he
sent me are extremely resistant to erosion.  Here is a picture comparing
one to a 1/8 inch pure tungsten rod after running a big arc about the same
length of time.

http://hot-streamer-dot-com/temp/erode.jpg

The tungsten rod is well discolored and the tip was burning off.  However,
the bullet is hardly discolored at all on the very tip!  They should make a
wonderful high power spark gap tip.

These "bullets" are apparently used as tungsten carbide tip inserts for big
rock drilling bits.

http://www.torquato-dot-com/acc.html

http://www.mining-technology-dot-com/contractors/drilling/sandvik_smith/sandvik_
smith6.html

This is something people that need super high power spark gaps should look
into...

BTW - I am seeing about borrowing a 2500 watt power supply from work to do
higher power testing :-))  It's three phase but can run from my home's two
phase in a pinch...  Maybe then I will get fire balls.  If not, we have
some 200kW ones... ;o))

Cheers,

	Terry