An impressive amount of conjecture and qty of recommendation here based on an external visual indicator and (apparently) an absence of any actual failure analysis. My $.02, start with x-sectional analysis. >-----Original Message----- >From: TechNet [mailto:[log in to unmask]] On Behalf Of Avni Selim Özçukurlu >Sent: Monday, July 01, 2013 6:36 AM >To: [log in to unmask] >Subject: [TN] Moisture in PCB > >Hello All, > > > > > >After a wave solder process of a PCB with lots of through-hole components >on it, I have seen that there are popcorn part near via on that PCB. The >flatness of the first layer of the PCB is gone after that process. I think >that moisture remaind inside PCB gets outsite during the wave solder >process and cause this problem. I didn't put the PCB in a vacuum oven >before wave solder. Is it possible that the problem is related of this. Is >there any alternative solution about that problem? > > > > >Actually I applied the heat up and vacuum to empty PCB before all process >of manufacturing. After that vacuum oven process, it has passed about 10 >days to start the wave solder process. During that 10 days, did PCB get >moisture inside? > > > >Thank you advance. > > > >Selim. > > >______________________________________________________________________ >This email has been scanned by the Symantec Email Security.cloud service. >For more information please contact helpdesk at x2960 or [log in to unmask] >______________________________________________________________________ > >______________________________________________________________________ >This email has been scanned by the Symantec Email Security.cloud service. >For more information please contact helpdesk at x2960 or [log in to unmask] >______________________________________________________________________ > >______________________________________________________________________ >This email has been scanned. > >______________________________________________________________________ >Aero Engine Controls is part of the Rolls-Royce Group, whose legal entity >is Rolls-Royce Engine Control Systems Limited which is registered in >England. >Registered office at Moor Lane, PO Box 31, Derby, DE24 8BJ. Company number >6686268, UK VAT number GB 939 396 075 > >______________________________________________________________________ >This email has been scanned by the Symantec Email Security.cloud service. >For more information please contact helpdesk at x2960 or [log in to unmask] >______________________________________________________________________ > >______________________________________________________________________ >This email has been scanned by the Symantec Email Security.cloud service. >For more information please contact helpdesk at x2960 or [log in to unmask] >______________________________________________________________________ > >______________________________________________________________________ >This email has been scanned. > >______________________________________________________________________ >Aero Engine Controls is part of the Rolls-Royce Group, whose legal entity >is Rolls-Royce Engine Control Systems Limited which is registered in >England. >Registered office at Moor Lane, PO Box 31, Derby, DE24 8BJ. Company number >6686268, UK VAT number GB 939 396 075 > >______________________________________________________________________ >This email has been scanned by the Symantec Email Security.cloud service. >For more information please contact helpdesk at x2960 or [log in to unmask] >______________________________________________________________________ > > > >______________________________________________________________________ >This email has been scanned by the Symantec Email Security.cloud service. >For more information please contact helpdesk at x2960 or [log in to unmask] >______________________________________________________________________ ______________________________________________________________________ This email has been scanned by the Symantec Email Security.cloud service. For more information please contact helpdesk at x2960 or [log in to unmask] ______________________________________________________________________