Homebrew PCBs

Yes, silicone is quite porous. It will stop liquid but vapor penetrates 
it quite easily.

Les

> Also, as a side note that might be slightly relevant and perhaps of use to someone here, in tests on Peltier modules, sealing out water vapor, epoxy was the only sealant that performed well. Silicone, surprisingly, did not...I guess it's fine for bathtubs and aquariums, but where there's heat cycling water vapor can still get through the molecular matrix.
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