Caitlen,
It is the general consensus of the IPC coating committees that coating the
board edges is not a value added item in most cases.  My company treats it
as a "don't care" condition.  If there is coating there as an artifact of a
spray coating process, that is OK, unless the board edge is being used
specifically for heat conduction.  In that case, the board edge is treated
as a required keep out zone and marked as such on the drawing.

Unless you have a good technical reason to either coat or not coat the
board edge, I suggest treating it as a "don't care".


Doug Pauls
Principal Materials and Process Engineer
Rockwell Collins

On Thu, Mar 1, 2018 at 7:45 AM, Caitlen Gahm <[log in to unmask]>
wrote:

> Greetings,
>
> We are wondering what the general thought is regarding whether or not the
> edge of a CCA/PWB needs to be conformally coated?  We received CCA's from a
> supplier and noticed that the edges were not coated.  Our thinking thus far
> is that since our drawing does not state that coating on the edge is
> optional or not required, it would be required.
>
> What we are curious to know is what the general consensus is regarding
> whether or not it is necessary to coat the edge of the CCA and instances
> when this would or would not be desired.
>
> Thank you,
> Caitlen Gahm
> Materials and Process Engineer
> Crane Aerospace & Electronics
>