From: John Allain <allain_at_panix.com>
>Make sure any big Caps are discharged (actually, I'd avoid PSU's as
>well), Otherwise, the materials used are all impermeable to water.
at least HV SMPS! THose have enough high volts on the high side caps
that discharge first is the rule.
>Metal rust takes a few days in water to really begin and modern plastics
>are waterproof, etc.
Water does not cause rust for the most part, oxygen does! However
if the water has any impurities or even soaps in it there is a risk of
electrolisys (so, wash and dry quickly).
>I wash in a tub of water to avoid the high temperature steam.
>As for drying, I do a sort of toweling off, usually with paper towels,
then
>air dry for safety, 1~2 days.
I put them in the dishwasher on the power saving setting (no reheater).
I've done boards like MVII cpu, Qbus RAM, PDP-8f front pannel and
most of the boards (not the core board, loose cores would be ripped off)
I deemed too dircty for dusting. Success is assured as commercial
cleaners for electronics assembly do that.
Over the years (20+) Ive done this and it's a great way to degrunge the
nastiest (esp cigarett smoke). It's a most do for any electronics that
has
had salt exposure (Salt eats metals!) as it tend to remain even after
dried
does become hydroscopic leading to long term problems.
Key things:
Not too hot. How hot it too hot? 200f (100c) or cooler is safe.
most Semiconductors (transistors, diodes, ICs) will safely stand
150c (at the junction) so that is the way to hot point.
once cleaned rinse well if any soaps were used.
Isopropanal can be used to dry (dewater) but it must be 95%
or better. Rubbing Alchohol is usually either 70% or 91% with
the
rest being... water!
Dry as soon as possible and throughly. A 190F (87) oven works
well or blow dry.
If there are any moving parts, lubricate as required with the
correct
oil (or grease).
Paper, temperature sensitive plastics and any suspect items like
closed
but not sealed items (relays, some switches) may need closer
attention
to insure they dont get wet.
Oh yes, a note on dry brushes or vacuums... remember you may be
generating
static and even TTL can suffer long term damage from low level ESD.
Allison
Received on Thu Aug 02 2001 - 17:57:57 BST