Hello all, I have a client who wants to pot the board I'm making to make 
it as indestructible as possible.

I haven't done this before, and wonder a few things.
Maybe someone would like to offer advice?

Heat.  The components being potted generate some heat, not a lot, and 
there will be a heatsink of some sort on the underside of the board. 
(only the top is being potted).  So I'm not too worried about this.

My main concern is what being potted may do the following component types:

Electrolytic caps: they have some sort of safety vent, right?  If 
sealed, and should disaster occur somehow, I figure failing in potting 
couldn't be any worse than failing in open air?

Inductors: I'm using 5 for dc/dcs, 4 of which handle significant current 
(2amps) in pulses.  They get pretty warm.  I just wonder if the potting 
compound could cause them to change behavior (inductance value, current 
capacity) in a significant way, by possibly squeezing them a little when 
it cures?  Seems unlikely, thought I'd ponder.

Crystal: there is a 10mhz xtal that needs to be reasonably accurate 
(250K baud serial coming in), and I remember somebody here saying once 
how potting a board made their xtal drift.  How problematic might this be?

Any advice appreciated.

Thanks all-
J



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