Brad, Thanks for your inputs. One thing I failed to mention was the non wetting occurrs on the thru hole pads on the wave solder side. I don't believe it is a case of heat being pulled away into the planes because the solder wets up the barrel of the thru hole pins. It just won't wet to the land areas. JIm Kittel -----Original Message----- From: [log in to unmask] [mailto:[log in to unmask]] Sent: Monday, March 11, 2002 9:09 AM To: [log in to unmask] Subject: Re: [TN] ENIG AND NON WETTING Jim, Sounds to me like your non wetting issue is related to the connector thermal planes. I have seen this time and time again. The culprit is always thought to be PWB, finish or connector, or assy process. If you have luxury of xsection of soldered connector (destructive) it will definitively show the effect of planes on the solder wetting. The only way to avoid this (if it is your problem) is redesign the I/O entry of planes to the connector by using trace entry (verses thermal), reducing or eliminating same hit thermals on same pin, reducing from four to two spoke thermal and or increasing OD on thermal diameter. As far as non wetting attributed to ENIG, we have not had a problem (never say never), but I still recommend moving away from it (using Silver or Tin). I differ in the upcoming IPC ENIG spec in that I prefer minimizing the amount of nickel to the 45-75 microinch thickness (and no high phos). This compels the user to FIFO or even better the JIT that has been discussed previously. Mind you, I am not knocking gold but in the case of an issue [i.e. Moonman dilemma] it is a nagging point of contention. Brad ---------------------------------------------------------------------------- ----- 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 ---------------------------------------------------------------------------------