On 8/16/2019 12:53 PM, Paul Koning via cctalk wrote:
That reminds me, Tubes and More ( https://www.tubesandmore.com ) sell a
contact cleaner used for vacuum tubes. That may be useful for cleaning
cards and card edge sockets. Deoxit is the product and comes in assorted
From what I remember, the detailed analysis involves an "electrochemical
series", which has metals like sodium at one end, copper closer to the middle, and
gold at or near the other end. Metals are compatible if their potential value differs by
less than a limit. The limit depends on the environment; in an office you can have a
larger limit than on a ship where you have salt spray, or a tire factory with lots of SO2
in the air.
There are also some twists; I think stainless steel is compatible with many things thanks
to the alloy ("stainless") properties. In fact, I think the subject came up in
connection with failure analysis of coin cell battery holders. The battery cases are
stainless steel; the question is what contacts are acceptable. Gold is; there may be
others but some things that are used in the market are not good choices.
types depending what you are cleaning.