How to encapsulate a small PCB?

[lorraineyappscoh]

New to this forum, I found a lead here for a sealant to encapsulate a small PCB but I don't know the process or whether I should use some kind of mold.

Brett (I can't find him here, now that I'm registered) asked about RTV, which I have identified for my project because it doesn't give off acetic acid, which causes the corrosion that can corrode the electronics but has the desired properties (air-, moisture-tight, resists vibration, impact, room temp curing) for finished encapsulation.

RTV-12 (a Momentive product, distributed by MG Chemicals in Canada; RS Hughes in U.S.) appears to be a product for my project but I don;t know whether I need to use a mold or dip and hang out to dry.

Anybody have any experience with encapsulating a small electric assembly for this neophyte electronics technician?

***Lorraine***

 

[(*steve*)]

In general you're looking for something that has the magic phrase "neutral cure".

There are apparently two major types of neutral cure silicone compounds, alkoxy and oxime. The former is better, and if the type of cure is not mentioned it will likely be the latter.

If you can fund a neutral cure silicone that lists itself as being suitable for polycarbonate, then you probably have an alkoxy cure silicone as oxime is not suitable for polycarbonate..