This is obviously a subject where the collective wisdom has plenty of
experience, so I won't reiterate.
One 'gotcha' that I haven't seen mentioned is ensuring that your
encapsulant will actually bond to the surfaces you are potting. For
example, PCBs with flux remaining and plastic mouldings (including looms
with moulded plugs) that still have release agent on them.
If there is a minute gap between the potting compound and the surface, it
will draw water in by capillary action.
For the same reason, don't use the potting as strain relief.

Steve.

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  Very funny Scotty.  Now beam down my clothes.
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Steve Baldwin                Electronic Product Design
TLA Microsystems Ltd         Microcontroller Specialists
PO Box 15-680                email: steveb@kcbbs.gen.nz
New Lynn, Auckland           ph  +64 9 820-2221
New Zealand                  fax +64 9 820-1929
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