Has anyone experience during rework of a multilayer board black residue appearing around plated through holes and even under the solder mask. Enclosed is a picture of one such incident. Analysis said it was the result of under cured epoxy. Some of my questions are: 1. Is this a reliability issue. 2. Can this be conductive is charred or burnt? 3. Is it a defect if under the solder mask and between plated through holes? Thanks, Jon --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 1.8e To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL) To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search the archives of previous posts at: http://listserv.ipc.org/archives Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-615-7100 ext.2815 -----------------------------------------------------