Electronics Forum | Mon Sep 26 16:48:32 EDT 2005 | PWH
Are you using masking? Conformal coat will de-wet (no pin holes usually, though) due to masking tape adjacent to affected areas if the tape glue chemistry isn't compatible with the conformal coat.
Electronics Forum | Tue Sep 27 11:46:02 EDT 2005 | jimby
surface tension of solder mask material on the board. Need to rough it up prior to board assembly. Use Silica (cabosil) and IPA mixture and rub
Electronics Forum | Tue Sep 27 12:04:35 EDT 2005 | Amol
Thank you patrick and jimb for you suggestions, will try them out and keep you posted. Amol
Electronics Forum | Fri Sep 30 11:00:14 EDT 2005 | Amol
i tried scrubbing the boards with xylene when they are hot from the bake, the the pockmarking seems to have almost disappeared! Amol
Electronics Forum | Tue Sep 27 09:18:17 EDT 2005 | patrickbruneel
Amol, Have you tried to conformal coat a bare board as it comes in from the board shop? If you still have the same results at least you know the problem is not related to your process. If you don't have the problem you need to have a closer look at
Electronics Forum | Mon Sep 26 15:17:54 EDT 2005 | Amol
Hi, I am spray coating PCB's with the above mentioned coating. The problem is that as soon as the boards are coated, there are pin holes on the surface that subsequently turn into localized areas of dewet on te PCB (its almost as it the coating is fl
Electronics Forum | Tue Sep 27 08:22:27 EDT 2005 | Amol
I am using masking tape, the 3M high temp blue masking tape. the problem though doesnt seem to be related to the masking tap as i am seeing pin holes and eventual dewets over entire ckt board (its almost as if the board has chickenpox under black lig
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