I agree with Brian on this one. We usually require baking on boards more then 6 to 8 months old. The FR-4 will have absorbed sufficient moisture in the (im)proper storage condition. Also verify for contamination on the components leads. Alain Savard, B.Sc. Chemical Process Analyst CAE Electronics Ltd. e-mail: [log in to unmask] -----Original Message----- From: Brian Ellis [mailto:[log in to unmask]] Sent: August 28, 2000 11:01 AM To: [log in to unmask] Subject: Re: [TN] Bubbles in through holes Franklin Rarely have I seen such an example of blowholing! You should patent your process for reducing the amount of lead in an assembly :-). Your board has simply absorbed a lot of moisture. A prebake will mitigate the problem, but prevention is better than cure. Brian Franklin D Asbell wrote: > Help... > > A customer has brought a problem to our attention. The yare experiencing > 'air bubbles' in through holes after wave soldering. > > The copper plating in the hole is averaging 1.25 mils, we have not seen > any compromised hole walls, only bubbles, they even extend up and out of > the hole next to the component leads. > > I have uploaded pictures on our website, any assistance would be > appreciated. > > These boards were fabricated here in Texas 13 months ago, the customer > did not bake the boards prior to processing. Thanks > > You can view these pictures at this link: > http://www.networkcircuits.com/technical.htm > > Franklin D Asbell > Network Circuits, Inc. > Irving, Texas 75061 ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ##############################################################