[Hallicrafters] A potion for cleaning and rejuvenating radios

[Mike Everette]

While working on my SX-28 I was confronted with a real
problem in cleaning it up.  The chassis, control
shafts, etc were covered with a layer of what looked
like oil soot, and nothing I tried -- solder flux
remover, conventional degreasers, or anything else we
normally resort to -- would remove it.

In desperation I tried wiping it down with a
penetrating oil called "P B Blaster," sold in
automotive stores.  This stuff is supposed to be a
super corrosion-buster, and very fast acting.  I had
once used it to free some long-frozen control shafts
in a BC-221 that had been deemed hopeless, which it
did just fine.

Using the aerosol P B Blaster VERY sparingly.  Put it
on a paper towel or cotton swab, coat the area you
wish to clean and then scrub it with the towel or
swab.  DO NOT DO NOT DO NOT "HOSE" the area!  This is
some pretty potent stuff, and I would not trust it
around anything with wax or plastic insulation; so
don't let it get into your I-F cans or power
transformer.  And be careful around the gum-rubber
grommets under the variable capacitor.

Within a couple of minutes the corrosion will begin to
break up.  A little more scrubbing with the P B
Blaster will remove most of it.  Then, wipe the area
dry with a cloth towel.  Follow this by scrubbing down
with "NeverDull," a cotton wadding product impregnated
with some kind of solvent.  (NeverDull is also found
in automotive stores; it comes in a metal can.) Scrub
until you get no more black or gray residue on the
wadding; this may take quite a while, but the results
are well worth it.

The chassis of my SX-28, which had been covered in
black grime and had the usual oxided look underneath
the sooty stuff, almost glows.  It's polished to a
nice shine; achieving that has taken a lot of elbow
grease but after I saw what a wonder the P B Blaster
was, it became a matter of pride to finish it.

The P B Blaster will also penetrate riveted ground
connections.  Let it work for a day or so and then
wash it out with a regular electronic-equipment
degreaser product.  I have noted a marked improvement
in the resistances of several in my receiver.

WARNING:

Use the P B Blaster and NeverDull with PLENTY of
ventilation.  The fumes are dangerous.  Either one is
bad enough by itself, but the two together are
extremely powerful.

DO NOT let the P B Blaster ANYWHERE NEAR a dial!  I
have not had to cope with this, but I believe it would
eat the markings in very short order, if not the dial
itself.

DO NOT spray P B Blaster into a trimmer capacitor.  It
is, however, very good for cleaning the wipers in a
variable cap -- but use it SPARINGLY.  A drop goes a
long way.

Again, DO NOT "HOSE" anything with P B Blaster.  The
best way to use this stuff is by soaking a cotton swab
with it (or a paper towel) and using that to apply it.

Be Patient.

All things in moderation -- but none to excess.

73

Mike WA4DLF

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