Re: Static Gap question.

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

Original poster: Bart Anderson <classi6-at-classictesla-dot-com> 

Antonio,

I've built a couple static gaps to adjust spacing with parallel pipes. I 
simply built a TCBOR gap in a pvc pipe on threaded rods.
The first attempt I used 2 screws per pipe. Found I should have done a 
better job drilling the holes.
The second attempt I used a single screw center to the pipe. This worked as 
I could simply spin the pipe to get it as parallel as possible to the next 
pipe and tighten down. Because it's in a pvc pipe, as the screws are 
extended inward, the electrodes can slowly be adjusted closer or further 
away. But, the problem is "way to much work and time" fiddling around.

I don't remember who (maybe Duck?), but several pipes were attached to a 
bendable piece of "something". As the this "something" was bent, it would 
increase or decrease the gap distances. That's probably the easiest design 
I've seen thought up. I think the next gap I set up will be something of 
that nature.

Take care,
Bart

Tesla list wrote:

>Original poster: "Antonio Carlos M. de Queiroz" <acmq-at-compuland-dot-com.br>
>Tesla list wrote:
> >
> > Original poster: Ed Phillips <evp-at-pacbell-dot-net>
>
> >         I'm not experienced in this area but did built one "parallel 
> pipe" gap
> > which worked quite well.  Used 3/4" couplings for copper pipe and
> > rounded the ends a bit by chucking the pieces in the lathe and using a
> > fine file until things "looked right".  I was surprised that when the
> > pipe was reasonably parallel there didn't seem to be any particular
> > tendency to spark at the ends only.  My gap has 7 pipes, with spacing
> > which will just "note break down" with the 12 kV NST connected open
> > circuit.  I found that by mounting the gap so the axis of the pipes was
> > vertical I had enough convection cooling to permit 30 second runs at
> > around 600 watts input to the transformer.  When I originally ran the
> > thing I had problems with fairly hard black "stuff" building up on both
> > sides of each gap.  Once I cleaned the pipes the first time this effect
> > almost disappeared.
>
>I found a (bad) picture of a parallel pipe gap that I use:
>
>http://www.coe.ufrj.br/~acmq/tesla/567gap.jpg
>
>My original intention was to be able to adjust the gap spacing by
>rotating all the pipes to the same angle. But this would require
>very precise positioning of the screws that hold the pipes at their
>centers, what was not the obtained result. Anyway, I can adjust the
>gap easily, but the angles betwen the pipes become irregular. It uses
>3/4" brass tubes, and becomes too hot after about 30 seconds too,
>without forced ventilation.
>
>It can be observed that the gap sparks at the edges when the pipes
>are not very parallel, but shows no big preference when they are
>almost parallel.
>Maybe because the sparks push the hot, or ionized, air to the sides,
>and then the spark keeps running along the pipes randomly, or because
>other elements close to the pipes distort the electric field.
>
>Antonio Carlos M. de Queiroz
>
>
>
>