Spray-on potting compound?

[blcpro]

Does anyone know of a spray-on potting compound. I have a circuit which needs to be insulated from water and moisture. Currently we are using a potting compound which is created by a mix of two of its ingredients. As well as this does work, when the mixture ratio is off or the ingredients get older, the potting takes many days (and sometimes weeks) to fully dry, and in the meantime the circuit is a sticky mess. I am looking for another solution which is easier to apply and less messy. Our goal is to water-proof the board. Enclosing the board is not an option. I would think there should be a spray -on non-conductive sealer out there somewhere, but I havn't been able to locate any... Have any suggestions??

 

[ScottyUK]

Try Googling

"Conformal coating"

and

"Conformal spray"

Most of these are either acrylic based or silicone based compounds which are intended to either improve the resistance to corrosion, or to reduce surface tracking on HV circuitry. The silicone type is a nightmare to remove; the acrylic type is less resistant to chemicals but is easier to remove.



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If we learn from our mistakes,
I'm getting a great education!

 

[sreid]

Humiseal is probably the best known for conformal coatings.

http://www.humiseal.com/

John C. Dolph is another company you might want to look at.

http://www.dolphs.com/

 

[blcpro]

Thanks ScottyUK and sreid! I'll check out both of your suggestions...

 

[buzzp]

One other note, most applications can use acrylic instead of silicon. The only difference I seen was in the price (both tested the same - silicon a lot more expensive). Your technicians will also thank you for not using the silicon. However, it has gotten better to work with but still not as easy as acrylic but not as hard as it use to be.

Conformal coating is also used when electronics are exposed to high humidity. I believe they spec 95%. So if your condensing then might still consider an epoxy or if your not opposed to using a product above and beyond the mfgs recommendations, then use the coating. In any case, water barriers should be with an epoxy, mild moisture protection can be done with a coating.

From your statment " I have a circuit which needs to be insulated from water and moisture." its not real clear what your goal is.

 

[legalimit]

we used to use a compound which set in a few seconds when exposed to ultra violet light. worked very well.