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Re: cap oil
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.)
-----Original Message-----
From: Tesla List <tesla-at-pupman-dot-com>
To: tesla-at-pupman-dot-com <tesla-at-pupman-dot-com>
Date: Friday, February 05, 1999 1:00 PM
Subject: cap oil
>Original Poster: Robert Volk <smrtmny2-at-earthlink-dot-net>
>
>Hi all!
>HELP?! I purchased a five gallon bucket of "mineral oil" from a local
>supplier. The bucket was labeled "Worm Gear lube 90" from 76 company. I
>questioned the dealer about it and he said it was mineral oil. When I
>opened it tonight to use it, it seemed darker than the mineral oil at
>the drug store. Is this normal? I've put too much work into my new
>polled poly caps to have them blow because of bad oil. The oil is not
>thick but it's definitely not as thin as the pharmaceutical brands.
>
>Can any one give me direction here?
>Thanks, Bob
>
>
>