Well Jack, sometimes the board edges are metallized so that it serves as a grounding path and sometimes as a thermal conduction path. In those cases, the presence of conformal coating interferes with the function of the board and so it should not be present. That is usually the question I ask designers all the time - will conformal coating in Location X interfere with the form, fit or function of the unit. If yes, then it is a keep out zone. Doug Pauls Principal Materials and Process Engineer Rockwell Collins On Mon, Mar 5, 2018 at 10:00 AM, Jack Olson <[log in to unmask]> wrote: > Typically the goal is to protect conductive surfaces, and board edges > don't often have conductive surfaces (and if they do, they might need to > stay exposed). > > If you have seen the board edges coated it is probably a result of the > method that was used to coat them (spraying or dipping), not because it was > required. > > > > On Thu, 1 Mar 2018 09:45:26 -0600, 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 >