Can someone tell me what the difference is between immersion gold and flash gold as a board finish? Is the 'flash' process a different type of plating process? Also, has anyone had any experience using Lead-free solder paste on a Flash gold finish? We're currently having some solder wetting issues with lead-free on flash gold where some of the pads on the boards exhibit complete lack of any wetting. It almost looks like what you get when you reflow solder paste on a ceramic substrate, where the solder just balls up. Is this an inherent problem with flash gold or do I have some kind of abnormal processing issue at the board vendor? Thanks in advance. Rick Thompson Sr. SMT Process Engineer SMTEK International, Inc. +1 (805) 532-2800 [log in to unmask] --------------------------------------------------- Technet Mail List provided as a free 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/html/forum.htm for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------