nospam said:
I have a Philips frequency counter with PCB mounted radio button type
switches. After about 10 years the switches were intermittent and a getting
to be a real pain in the arse.
I tried cleaning them several times with solvents (PCB cleaner and IPA tape
head cleaner) which made little difference I tried some WD40 which worked
wonders. It is probably another 10 years on now and the switches are still
fine.
I have also used WD40 very sparingly as a lubricant for PGA processor pins
in the days before motherboards had ZIF sockets. It made a huge difference
to the force required to get a chip in or out and had no noticeable
detrimental effects.
Well, so far, after reading at least ten followups to this thread,
you're the only one that's for using WD-40. The others are all against.
Sorry to say it, but I agree with the others. WD-40 leaves a film that
attracts dust and just causes more problems later.
A week ago I took one of the smog control sensors apart on my car, and
found it to be working okay, but I'm still getting the trouble light.
The sensor has a spring loaded pin that sticks out and touches the
diaphragm, and as the pin is pushed in, the resistance of the sensor
varies from 2k or so to zero. The end of this pin had a small dab of
white grease to lube it. It's essentially a pot with the ends at ground
and +5V, and the wiper at somewhere in between. But the three pins on
the connector were coated with a clear grease, which prevents corrosion
but doesn't insulate the mating contacts from one another. This
connector is sealed with a rubber gasket to keep out all that nasty junk
from the engine. So these sensors rely on a small amount of special
grease and a good seal to protect them from corrosion, and keep them
from giving the wrong position info to the controller.
Whatever lubricant you use on a switch, it should be designed to do the
proper job, and WD-40 was not designed for that purpose. Use a contact
cleaner and lubricant that's made to clean and lubricate contacts.