On Mon, 11 Jul 2016 19:48:43 -0700 (PDT), Phil Allison
wrote:

Jeff Liebermann wrote:


I also found that I can make things worse
by mixing my own and using too much oleic acid. It will not attack
gold or silver plated contacts, so those are safe. So, if you're
using the old stuff with oleic acid, wash off the contacts with
alcohol after you've removed the black silver oxide coating.

** The dark coating that forms on silver is *silver sulphate* (aka Ag2S).

I stand half way corrected. Y'er right. Most of the tarnish is
silver sulphide.
https://en.wikipedia.org/wiki/Silver_sulfide
"This dense black solid constitutes the tarnish that
forms over time on silverware and other silver objects."
Also, silver oxide is also dark colored:
https://en.wikipedia.org/wiki/Silver_oxide
"Tarnish" is a mixture of silver oxide and silver sulphide, in
proportions that vary with whatever is causing the silver to tarnish.
Silver sulphide tarnishes rather quickly in the presence of sulphur
bearing compounds, while silver oxide takes months to accumulate.
https://en.wikipedia.org/wiki/Silver_oxide
"...silver needs hydrogen sulfide to tarnish, although
it may tarnish with oxygen over time."

Luckily it is quite soft and wears off switch contacts in normal use
so a build up may occur which can be flushed clean with products
like WD40.

The idea of using oleic acid on electrical contacts worries as it
must become conductive under enough voltage.

What do you mean "must become conductive"? Do you mean that the oleic
acid becomes conductive, or perhaps the contact cleaner? Unlikely
because the oleic acid will attack copper and therefore must be washed
off by something after its used to clean the oxides, sulphides, crud,
dirt, tar, and oils off the contacts.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558