Re: oil quenched spark gap

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

Original poster: "BunnyKiller by way of Terry Fritz <twftesla-at-qwest-dot-net>" <bigfoo39-at-telocity-dot-com>

Tesla list wrote:

>Original poster: "Alfred Erpel by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<alfred-at-erpel-dot-com>
>
>Howdy All,
> 
> 
>    I just built the oil quenched spark gap shown here
><http://www.neongold-dot-com/public/1/oil_quenched_spark_gap.jpg>http://www.neo
>ngold-dot-com/public/1/oil_quenched_spark_gap.jpg . The unit is shown partially
>filled with oil, but it is totally filled when it is running. The 4 gaps were
>set to a .003 opening (another .001 and they wouldn't fire). The submersed
pump
>was a continuous duty submersible pump available from Grainger for about $22.
>The oil was EDM oil purchased in a 5 gallon pail from MSC. It is rated to
break
>down at about 50,000 volts. This is not it's dielectric strength volts/mil but
>the voltage at which the oil should decompose. I ran a Franceformer 6020SE 6kv
>150 VA transformer across the 4 gaps connected in series for about 20 minutes.
>There were bubbles issuing forth from between the 4 gaps which immediately
>perplexed me. Periodically I had to move the gaps closer because the spark
>would suddenly stop. The transformer barely got warm, but was slightly
>perceptibly above room temperature after 20 minutes. Suddenly the unit
sprung a
>leak and was squirting oil out at high pressure. I shut it down and it was
then
>that I realized that the bubbles I saw were pressurizing the unit. So I assume
>that the oil was breaking down, but it isn't supposed to. 
> 
>Anyone have any ideas on this. Like is there a different oil or substance that
>would be a good idea to run through this? Etc. ?  If I get this working, I
will
>post complete shop blue prints in .pdf format for anyone to use.
> 
> 
>Regards,
> 
>Al Erpel
> 
> 
>
>
>
>
>
Hi Al...

We use an EDM machine at work and it produces bubbles when it is 
cutting...  even tho the oil isnt supposed to asorb water ( moisture) it 
still does. the bubbles ( what Ive been told by the Eng. in the cutting 
lab) is the moisture breaking down into Hydrogen and oxygen... a small 
portion of the gasses being produced are the trapped gasses in the metal.
I suppose a vent may be needed for your enclosure.....

Scot D