same problem observed on moulding compound wick to the component's leads for PTH parts... (especially, cheap capacitor made in other side of the earth)--- if you test for the in coming part using the long leads - everything OK, the wick only take place near the body - where you try to reduce stand off and insert a bit deep into the hole... (if you look closely, it showed slightly demarcation on PTH solder joint--- but inside is non-wetting... hard to FA). On Feb 8, 2018, at 7:11 AM, Stadem, Richard D wrote: > Yes, that is a common occurrence and is one reason why many > connectors are exempt from coating. Conformal coating's capillary > action is incredible. It will seep into any and all space > available, and once in there and cured, will insulate the surfaces > covered. > > -----Original Message----- > From: TechNet [mailto:[log in to unmask]] On Behalf Of Jack Olson > Sent: Wednesday, February 07, 2018 4:17 PM > To: [log in to unmask] > Subject: Re: [TN] IPC-CC-830 (Conformal Coat) > > sorry for the long delay (and thank you for the responses) but as I > was reviewing these posts I had another question: > > Have you ever heard of problems with conformal coating material > wicking up the connector leads and causing intermittent connections? > > thanks again, > Jack > > > On Wed, 6 Dec 2017 14:09:46 -0500, lduso - Diamond-MT.com > <[log in to unmask]> wrote: > > (..snip...) >> It's up to me to decide how close to J1 to get with the coating. I >> once >> coated the leads of all the fine-pitch connectors and the customer >> said >> that was too close. The next customer will reject the work if I don't >> coat the leads.