We have a number of printed wiring assemblies that are showing indications of bad (?) solder mask. Tape test is fine on PCBs prior to wave solder. And overall appearance prior to wave solder appears normal. After the wave soldering process, boards are water washed and dried. There is a powdery, whitish, streaky look to the boards. This does not come off, and it apparently is not on the surface. It appears to be inside the solder mask. Tape test still passes, no blistering or loss of adhesion is apparent. The customer wants Class 3 standards to apply, and cosmetically this looks terrible (yes, 610-C says okay - but also says customer must determine what is acceptable). Checking with a third party board house, we are being told this may be caused by the solder mask not being applied over clean PCB, or improper mixing of the mask and catalyst. Our concerns are: what is the long term consequences - will this break down, allow growth of something, or what. The boards are used in power distribution systems for 19 inch computer racks. Any help would be appreciated. Tom Parkinson WinTronics, Inc. --------------------------------------------------------------------------------- DesignerCouncil Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF DesignerCouncil. To set a vacation stop for delivery of DesignerCouncil send: SET DesignerCouncil NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------