Re: Aluminum electrodes in TCBOR static gap


On Wed, 13 Oct 1999, Tesla List wrote:
> This leads me to believe that aluminum is a very poor conductor at high
> voltage levels. I'm still puzzled on why it worked well in the first few
> seconds, but then stopped. I looked at the spray pattern and it doesn't
> seem to have anything that would stop or impede spark movement. 

I'm far from being an expert on this, but I'd suspect a top layer of Al
has oxidized to non-conductive (or for HV to high resistance) Al2O3. 
Happens very easily and very fast even at "lower" temperatures - I know
this from blasting an aluminium pencil sharpener over a small flame... ;o)

Maybe sanding the aluminium parts will make it once again work 30 seconds
more? Other possibility is that the cap has broken down?

 Jan Florian Wagner
 jwagner-at-cc.hut.fi, petwag-at-kolumbus.fi