Bob, My two cents for the Friday - If I read the question correctly, you are asking about adhering either a 0.1um tin plated part, or a 2um tin plated part to bare, non-metallized FR-4. Given that the tin plated components are virgin/not oxidized, it is my belief that the adhesive will adhere much better to the bare FR-4 than to either of the tin plated components. In the virgin state, I would not expect much, if any difference between them. Should the Sn plated components have been subjected to a thermal exposure of some kind - what was formerly beneath the thin Sn plating may now also be oxidized and corrupting the surface making it's interface weaker sooner. Heat cure adhesive, UV, or room temp? - I am not a great fan of adhesively bonding [long term] to Sn. The higher the heat cure, likely the worse it will get. Will see how much other traffic this starts :-) Steve -----Original Message----- From: TechNet [mailto:[log in to unmask]] On Behalf Of bob wettermann Sent: Thursday, April 09, 2009 11:17 AM To: [log in to unmask] Subject: [TN] Friday Theorizing Dear Technetters: Has anyone done any adhesion testing of a 2um tin-electrocoated surface (copper carrier) to FR-4? How about a 0.100um tin electrocoated surface? Can someone theorize on which might give better adhesion using a 2-part epoxy? Regards Bob Wettermann BEST PH 847-767-5745 --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 ----------------------------------------------------- --------------------------------------------------- Technet Mail List provided as a service by IPC using LISTSERV 15.0 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 -----------------------------------------------------