Re: Rotary Spark Gap

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

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

Hi CJ,

>At 12:55 AM 7/4/2001 -0700, you wrote: 
>I have been looking through a great deal of other coilers websites and 
>rotary spark gaps. I was planning on using a rotary spark gap in my next 
>tesla coil, but I am unsure if I can build it well enough. Can it be done 
>without using any power tools or extensive knowledge in machine work? I also 
>had some questions with the aspects of the RSG. 
> 
>1) What's the best way to attach the electrode onto the disc so that they 
>stay on well (and adjustable).

I like to run some type of screw through holes in the disk.  This is real
easy and your can make the tips adjustable and replaceable.  I use brass
acorn nuts.  One does have to be sure they stay on tight so as not to go
flying off but if anything gets loose, the tips will crash before that
happens.  Pics of some of mine are at:

http://hot-streamer-dot-com/TeslaCoils/MyCoils/BigCoil/Rgap.jpg
http://hot-streamer-dot-com/TeslaCoils/MyCoils/SmallCoil/small_gap1.jpg
http://hot-streamer-dot-com/temp/OldGap.jpg

Some people have tungsten electrodes but I will have to defer to them on
how to do that.  The electrodes get really hot so you almost have to have
some type of metal holder to dissipate the heat.

>2) When pressing several disks together, is it better to glue them together 
>or to use nuts to hold, or both? 

I would just bolt them together since glue is sort of a messy business and
you could easily cause imbalances.

>3) What's the difference in using 4/2 stationary electrodes 
>advantages/disadvantages? Is it possible to use just 1. (worrying about the 
>accuracy and the alignment of my electrodes)

1800 RPM sync gaps need four electrodes and 3600 RPM gaps need to for the
gap timing to work out right.  Async gaps can use any number of electrodes
but you probably want an even number.

> 4) How do you cut the tungsten electrode smooth and even. 

By a nice brand new file.  File a notch in them and snap the tungsten
apart.  Then file them flat or round or how you wish.  Tungsten files well
but it wears the file quickly and it is slow going but can be done
reasonably easily.

>5) How much does the dia. of the electrode affect performance (in a low 
>powered coil)

You want to big enough so that the electrodes will not arc to the motor
shaft but not too big that it gets to be hard to balance or loads the motor
down.

> 
>I will keep 'em coming as a try making more plans/drawings. 
> 

Cheers,

	Terry


>CJ Moore
>60871583
>