[R-390] Cleaning Chassis and rebuliding -Long

[blw]

> I dumped the silver parts into the liquid and scrubbed them with a
> toothbrush.... the Silverdip has magic properties and restores a clean
> silver
> finish to most parts after about five minutes immersion. (BTW it is only
> about =A32 a bottle, enough for about 4 R390s). So having rewound the magne=
t
> for the whip antenna channel and re assenbled the relay parts, I now have=
 a
> pretty good looking coax relay at the back of my set.
>=20
>> It restores that shine by taking off the oxides, and again, word was som=
e
> of the un-oxidized metal as well.  That's a problem with plating.  Better=
 to
> use something like DeOxit.  Even though it doesn't magically shine that
> well, if you just burnish the mating surfaces and apply some DeOxit, that
> generally does the trick without risking what's left of the plating.
>=20
> Barry



Yes, there was some good discussion on oxidation....maybe last year. I thin=
k
we even debated how to clean tube pins.

I think the main point is that anything liquid will leave some film behind
when it dries. Tape manufacturers recommended alcohol to clean tape heads
when recorders were very primitive in the late 60's. A few layers of dried
alcohol was enough to prevent recording and playback in some cases.

I always try to use a soft eraser first to burnish and clean the metal
surfaces. Then, DeOxit is applied to finish up the job. If I had to use a
substance to cut through crud or corrosion I would clean the metal the best
I could, wipe dry, use the eraser to polish the metal surface clean, and
then apply DeOxit. DeOxit is the only thing I want between metal to metal
contacts.


Barry