Hi Earl, I'm not sure if I understand you correctly, you mean topside-reflow worked fine, but wetting problems on the wave-soldered bottomside ? If so, perhaps the time between reflow and wave was longer than it should ? ENIG is normally promoted as a finishing that keeps it's solderability as long as the bare board hasn't been in the storage room too long. In reality however, the time between the subsequent soldering steps is also very important. We've had some bad experiences where after reflow we had to wait several weeks for leaded components to be supplied. Nowadays we don't start production until we've got all the parts. We haven't had any solderability issues since. Daan Terstegge SMT Centre Thales Communications Unclassified mail Personal Website: http://www.smtinfo.net >>> Earl Moon <[log in to unmask]> 03/10 12:26 pm >>> Folks, Don't know yet for sure but I may have gotten my client and self in a bit of a problem. Used this very highly qualified fab supplier for some time. Used ENIG from them and other quppliers equally qualified and never had this issue arise and I'm not sure of the cause. I know even the best loose the recipe but rarely. Can't post the pictures now as I'm on a different computer without them. The non wetted pads are on the wave solder side (my assembly house didn't reflow the important top side using paste per my instructions. Some pads are partially wetted to about 50%. Many through hole pads wetted and many didn't. The board was requested to be a solder mask over bare copper, ENIG. Type. As the ENIG was the last wet chemical process, I'm trying to understand what is the problem. I mean, there is no resist left as the gold looks as it should and SM stripping was done over bare copper. What contamination could cause such problems? Thanks, Earl Moon --------------------------------------------------------------------------------- Technet 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 Technet To temporarily halt delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest 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 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- Technet 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 Technet To temporarily halt delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest 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 ---------------------------------------------------------------------------------