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Re: cap oil
> Original Poster: "jim lux" <jimlux-at-jpl.nasa.gov>
>
> That is NOT what you want. I'll bet the stuff stinks too? Gear oil typically
> has highpressure lubrication additives (like Molybdenum disulfide) and anti
> oxidants, etc. All of which you don't want.
>
> It is in fact mineral oil based, but so is the stuff you put in your
> transmission or crankcase, neither of which is particularly suitable for
> insulation purposes.
>
> You want transformer or capacitor oil. Shell Diala would be an example.
>
> The stuff you want is clear or slightly yellowish and smells basically like
> Vaseline. Ask for the MSDS on it, which will tell you if it has additives
> (you don't want any, except for some antioxidant like Vitamin E or BHA or
> BHT).
>
> The other thing about insulator oil is that it has low water content, which
> is very very important for your application. A few ppm of water dramatically
> reduces the dielectric strength.
>
> You can dry oil that is "wet" by running it through any of a number of
> chemical drying agents (metallic sodium, Calcium Chloride, Silica Gel, etc.)
Yes, it did smell, Jim. It smelled just like auto oil, though not as
thick. When I examined the label closer, it said "highly flammable-do
not expose to fire or flame". Hmmmm. Is a cap exposed to flames?! Since
I wasn't into pipe bomb capacitors, I called the retailer and he had
just gotten shipment of pure mineral oil in. I was able to exchange it
straight across, I filled my new caps, and am slowly breaking them in
today.
Thanks to everyone for the responses!
Bob V