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Jeff Liebermann Jeff Liebermann is offline
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Default Repaired Harbor Freight digital caliper

On Sun, 20 Nov 2011 23:47:58 +0000 (UTC), gregz
wrote:

Jeff Liebermann wrote:
On Sat, 19 Nov 2011 22:19:11 -0600, Jim Yanik
wrote:

I wonder if Cramolin/DeOxit would work on the conductive strip?


http://siber-sonic.com/electronics/caig.html
Sorta. The original Cramolin contained about 5% oleic acid, which is
great for removing surface oxidation, but is also mildly corrosive to
copper. The current version is DeOxit from Caig Labs. It comes in an
amazing variety of forms, and is allegedly non-corrosive.
http://store.caig.com/s.nl/sc.2/.f
The MSDS data shows the active ingredients as a "trade secret". Oh
well.


I never have been able to get much visible effect of so called corrosion
removers. Oleic acid probably being best, but supposedly the cramolin
chemist also had input on making deoxit. On a short term test I can visibly
wipe off oxide with an alcohol swipe, being just as effective. Most of the
removing is mechanical in nature, and any liquid helps.


The oleic acid is only about 5% of the contact cleaner. Over a period
of time, it will help remove any oxide deposits. However, at such a
low concentration, it should not be expected to dissolve a substantial
oxide accumulation. Basically, any detergent will do as well if you
can live with the residue.

More on Cramolin:
http://www.pitt.edu/~szekeres/caigcram.htm
http://siber-sonic.com/electronics/caig.html

Cleaning brass clocks. Note the section on oleic acid.
http://www.abbeyclock.com/brass2.html
The oleic acid therefore has two functions: to remove
the oxide layer from the metals and to act as a soap
to remove the dirt and oils. The cleaning solution
has about 90% ammonia solution with about 5% oleic
acid and 5% acetone added, thereby leaving plenty
of excess ammonia molecules to keep the solution
alkaline.
The acetone is to accelerate evaporation. Oleic acid also has the
advantage of being common, cheap, and non-toxic. It's a by product of
corn and veggie oil production.

http://www.dialcover.com/components.html
Scroll down to "Cease and Desist" contact cleaner. Much the same as
my home made formula except I won't use acetone because it eats
plastic. Ordinary isopropyl alcohol is safer.

Homebrew cleaners and protectors:
http://www.pitt.edu/~szekeres/cleaner.htm
The comments on the effects of silicones plus salt in WD40 are
interesting.

--
Jeff Liebermann
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