One test for a counterfeit (U.S.) bill is to rub it on a piece of paper.
The ink on a genuine bill never dries, so you'll always get a slight
smear. Somehow that doesn't seem like a good thing to leave behind on a
relay contact you're trying to clean.

Roy Lewallen, W7EL

Richard Clark wrote:
. . .
You could also use a typing eraser to clean the mating surface. This
is an old board cleaning tip that was NASA approved back when there
were typewriters to need typing erasers. These erasers had the right
amount of abrasive without having too much. The same goes for a
dollar bill having just enough abrasive (useful for cleaning fouled
relay contacts). But none of this really takes care of the problem.
It simply puts you into the lock-step of a chemical dependency.
. . .

Richard Clark wrote:


This all returns to the same lack of need when tightening up the
contact spring would do the trick just as Mark described. The "good"
chemicals that have been suggested are not cheap, and the "bad"
chemicals (Hydrochloric Acid no less) are extremely cheap to get, but
a pain to get rid of.

Not that I'd ever use Hydrochloric acid, but aren't we talking about a
simple acid/basic reaction to turn it into something benign? I used to
use an acidic Cibachrome photo developing solution which we used some
magnesium hydroxide to neutralize.

- Mike KB3EIA -

On Mon, 27 Oct 2003 20:39:04 GMT, Mike Coslo
wrote:

Richard Clark wrote:


This all returns to the same lack of need when tightening up the
contact spring would do the trick just as Mark described. The "good"
chemicals that have been suggested are not cheap, and the "bad"
chemicals (Hydrochloric Acid no less) are extremely cheap to get, but
a pain to get rid of.

Not that I'd ever use Hydrochloric acid, but aren't we talking about a
simple acid/basic reaction to turn it into something benign? I used to
use an acidic Cibachrome photo developing solution which we used some
magnesium hydroxide to neutralize.

- Mike KB3EIA -

Hi Mike,

Yes, I've done darkroom work too and I have worked professionally with
acids in chemistry analysis (Titration and back-titrations). The
difference there is that I could always measure my reaction products
with indicators or probes or test strips. None of that has been
offered as part of the regimen for fixing what an allen wrench can do
quite well with none of the risk of uncontrolled exposure. If you
have to buffer and wash the coil, you may as well skip the acid anyway
and do it right.

73's
Richard Clark, KB7QHC

Richard, When you are wrong then why not admit it instead of digging a
hole for yourself
Yes, you can clean a contact by drawing a clean piece of paper thru it
but never anything as abrasive as a file or sandpaper as the deposit
left is offtimes worse than the original contact contaminate.
Look back at Roy's comment with respect to wipe. It is probably for a
circuyit board insertion and where wipe is the one and the same as a
scrubbing
dimension, It says nothing about pressure. You also referred to
bifircated contacts in one of your wrigglings, a bifocated contact can
help in a life or reliability test only because the odds of closure
are enhanced because you have a backup contact. Unfortunaley if the
wipe or scrubbing action is not sufficient for closure it will not
help.....two bad apples does not trump
one single good apple. The fact is that you will do anything to knock
me and are now reducing yourself to 'on the fly' thoughts, thus Reg
said "garbage to another post contact by yourself as I also did with
your pressure statement.
Straighten yourself up. You are a very knoweledgable person even
though you do not have a technical degree but your studies in
Literature and Shakespere should not hold you to the of the voice of
Punchinello when you decide to dig a hole for somebody else.
Why not put hate thoughts aside and get back to sharing your
considerable
knoweledge in the electrical field
Regards
Art



Richard Clark wrote in message . ..
On Mon, 27 Oct 2003 03:58:10 GMT, wrote:

How about silver polish - is that any good for this?
Someone told me it is - but I don't know.

Hi OM,

If silver polish worked, then you could as easily boil it in water in
an aluminum pan - does the same thing.

You could also use a typing eraser to clean the mating surface. This
is an old board cleaning tip that was NASA approved back when there
were typewriters to need typing erasers. These erasers had the right
amount of abrasive without having too much. The same goes for a
dollar bill having just enough abrasive (useful for cleaning fouled
relay contacts). But none of this really takes care of the problem.
It simply puts you into the lock-step of a chemical dependency.

This all returns to the same lack of need when tightening up the
contact spring would do the trick just as Mark described. The "good"
chemicals that have been suggested are not cheap, and the "bad"
chemicals (Hydrochloric Acid no less) are extremely cheap to get, but
a pain to get rid of.

73's
Richard Clark, KB7QHC