On Tue, 12 Jul 2016 23:07:52 -0700 (PDT), Phil Allison
wrote:
Jeff Liebermann wrote:
** 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.
** There is simply no silver oxide formed at room temp.
https://en.wikipedia.org/wiki/Tarnish
Tarnish is a thin layer of corrosion that forms over copper,
brass, silver, aluminum, magnesium and other similar metals
as their outermost layer undergoes a chemical reaction.
Tarnish does not always result from the sole effects of
oxygen in the air. For example, silver needs hydrogen sulfide
to tarnish, although it may tarnish with oxygen over time.
I'm not sure how much time is required, but my guess is that it's in
months.
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?
** I was referring to products that use oleic or any other acid in the mix.
Even the smallest leakage current can be a disaster with electronics -
track to track on PBCs or between plate and grid pins of a vacuum tube
or its socket.
Good point. However, I couldn't find anything on the electrical
conductivity of oleic acid.
https://www.ebi.ac.uk/chembldb/index.php/compound/inspect/ChEMBL8659
https://pubchem.ncbi.nlm.nih.gov/compound/445639
If I feel ambitious, I'll try some on a glass slide with my antique
hand crank Megger meter. Something like this:
http://www.richardsradios.co.uk/megger.html
Last time I used it, I managed to zap myself, so I'm not thrilled with
doing this. Still, it's handy for measuring leakage resistance and
torturing customers to pay my exorbitant fees.
Products like WD40 are certain to cause no leakage.
Well, at least you have the correct approach. If you don't know, try
it and see what it really does. It's much better to test than to
speculate. However, my opinions and experiences with WD40 are
somewhat different than yours. I'll use it for all kinds of
mechanical devices, but I keep it away from electronics for the same
reason you seem to dislike oleic acid. Both tend to migrate to where
they don't belong.
Drivel: No matter what the topic of the discussion, if it is about
chemicals for electronics, the discussion will inevitably gravitate
down to WD40.
--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060
http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558