Re: newbie question - spark gap and toroid

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

Original poster: "robert heidlebaugh" <rheidlebaugh-at-desertgate-dot-com> 

Ho Shu Huang : Aluminum has a major problem. As the power arc 's the surface
oxygen combines with the metal forming an insulating coating that will stop
the electric current. The arc contacts should be conductive of copper,
nickel or tungsten. Bronze or brass work well if cleaned from time to time.
The connecting wires should be large enough to carry the current.
      Robert   H
-- 


 > From: "Tesla list" <tesla-at-pupman-dot-com>
 > Date: Sun, 31 Oct 2004 12:48:23 -0700
 > To: tesla-at-pupman-dot-com
 > Subject: newbie question - spark gap and toroid
 > Resent-From: tesla-at-pupman-dot-com
 > Resent-Date: Sun, 31 Oct 2004 12:50:28 -0700
 >
 > Original poster: "ho \[shu\] huang" <shuhuang-at-singnet-dot-com.sg>
 >
 > Hey!
 >
 > I've got my tesla coil to work but I've got a couple of quick questions for
 > you pros out there: -
 >
 > 1. My SG spark gap's made from aluminium curtain rail, not copper pipe. The
 > rail is flat, so it's easier to mount. Does it matter? My coil works, but
 > I'm not sure if aluminium hinders performance in any way.
 >
 > 2. Does it matter that air isn't blown directly at the sparks? Do the
 > sparks require a lot of air to be "quenched", or will a bit of moving air
 > be enough? In other words, is more wind better?
 >
 > My spark gap (pic here: http://web.singnet-dot-com.sg/~shuhuang/spark_gap3.jpg
 > ) sparks at the ends of the rails, which is sort of shielded by the 10mm
 > thick plastic support. I can easily reconfigure it so that the sparks get
 > most of the breeze from the fan, but I'm wondering if it's worth the
 > effort. The fans blow, rather than suck, BTW.
 >
 > 3. I used 2 aluminium wok covers joined together
 > (http://web.singnet-dot-com.sg/~shuhuang/tesla_coil_lab.jpg ), ~210mm wide and
 > 320mm in diameter, as a toroid but I suspect a traditioanl toroid might
 > work better. Believe it or not, I'm actually having a hard time flexible
 > drainage pipe. It's apparently not used very often any more...where I live
 > (SIngapore) anyway. I came across the pool float toroid design on a
 > webpage, and I've found one on sale cheap. It's 23" in diameter and 8"
 > thick. Is that too big a toroid for my 15kV 30mA, 90mm 900 turns AWG 24
 > wire secondary coil, set up?
 >
 > thanks!
 >
 > Shu
 >
 >
 >