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Re: Helium(?) gap test.
Try setting up a container to allow the heavier gases to fall, and let
it sit for two weeks before experimenting again. Make sure that you have a
nozzle on the top of the container, use a vacumm pump to remove it, and
don't tilt, or shake the container.
>Original Poster: Terry Fritz <terryf-at-verinet-dot-com>
>
>Hi All,
> I repeated my spark gap voltage test with helium from a balloon filling
>kit sold at the party store today. As Bill mentioned a few days ago, this
>stuff is NOT pure helium. It will allow contact burning. I don't know
>what the other gasses are but they do cause gap damage. This gas also has
>very different properties from the argon. Instead of having a clean arc at
>the gaps, it tends to have more of a plasma glow. The losses are very
>high. Helium has a very high heat capacity that may account for the loss.
>Since this gas is not pure I can't say too much as to how pure helium will
>behave. Also the leak rate of helium is very high which is not desirable
>in my case. For now, I think the welding grade of argon is the best gas to
>use. Helium may work but my admittedly flawed tests today suggest it may
>have problems too.
>
>Here are the gap voltages but don't take them too seriously since the gas
>is contaminated.
>
>Gap Width (mil) Firing Voltage
>4 550
>8 620
>12 850
>16 920
>20 1090
>24 1200
>28 1250
>
>
> Terry Fritz
>
>
>