A significant amount of industrial electronics is potted. No problems. You should be concerned with internal heat build-up. How hot do the inductors get? I've used several gallons of potting compound over the years and don't recall any problems developing because of it. Don't recall if anything had crystals in it, though. Your best bet is to obtain some of the potting compound that you plan to use and see what happens to your product. dwayne At 01:12 AM 7/2/2009, Jesse Lackey wrote: >Hello all, I have a client who wants to pot the board I'm making to make >it as indestructible as possible. > >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. -- Dwayne Reid Trinity Electronics Systems Ltd Edmonton, AB, CANADA (780) 489-3199 voice (780) 487-6397 fax www.trinity-electronics.com Custom Electronics Design and Manufacturing -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist