Jeffrey, With the given surface finishes listed below, try running them through lead-free soldering temperature cycles (6X) and check the wetability of each. You might even try 2 or 3X and you will see considerable differences. After you try this you might not see things the same as you do below. : / Regards, David Hoover - aka Groovy PS- I tend to agree with George Milad. ----- Original Message ----- From: "Jeffrey Bush" <[log in to unmask]> To: <[log in to unmask]> Sent: Monday, March 29, 2004 5:15 AM Subject: Re: [TN] Black Pad Prevalence ENIG processes are costly to maintain and this finish if not the preferred solution for soldering planarity. The Nickel deposition process requires a good deal of attention and the main issue is the process going south is the lack of work being processed through it. The cost of ownership of the ENIG outweighs the benefits sharply and both tin and silver exist as economic alternatives to gold and do not have the disadvantages which go beyond the black pad condition. Silver appears to be the most effective alternative as it is more forgiving for time delays between thermal excursions, but many assemblers have adapted their process to also run tin effectively, which has the lowest overall cost impact per unit. Stay away from ENIG and evaluate tin and/or silver. Jeffrey Bush Director, Quality Assurance and Technical Support 76 Technology Drive - POB 1890 Brattleboro, Vermont 05302-1890 Tel. 802.257.4571.21 Fax. 802.257.0011 [log in to unmask] http://www.vtcircuits.com -----Original Message----- From: Paul Truit [mailto:[log in to unmask]] Sent: Saturday, March 27, 2004 10:03 AM To: [log in to unmask] Subject: [TN] Black Pad Prevalence I have searched the archives and have found lot's of good info but nothing in regard to the prevalence or the statistical occurrences of this event. I have run tens of thousands of ENIG boards and I haven't observed this defect but I am concerned enough to ask. Is this a board fabricator controllable issue that has been minimized? Have you observed this phenomenon? How often will this occur? Is immersion silver the better way to go to assure the reliability and quality of the products? -- Paul Truit, Mfg. Eng. RBB Systems, Inc. 4265C E. Lincolnway Wooster, OH 44691 Ph. (330) 567-2906 ext 514 Fax (330) 263-5324 Email: [log in to unmask] --------------------------------------------------- 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 847-509-9700 ext.5315 ----------------------------------------------------- --------------------------------------------------- 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 847-509-9700 ext.5315 ----------------------------------------------------- --------------------------------------------------- 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 847-509-9700 ext.5315 -----------------------------------------------------