As asked I think two areas are jumbled here. Pb-free processing will require a higher process temp, but this is to accommodate the higher MP of the Pb-free solder, not the finishes. By and large lots of finishes on component leads do not contain lead now and may never have. Calling them quote lead free unquote doesn't change anything technically. By the same token a change from a finish which happens to contain lead to one of these no lead containing finishes is almost certainly not going to have a huge impact. You could even now be using a dual sourced component, one with lead and one without, for example, and not making any distinction. It is true that some alternative finishes may involve a theoretical small increase in soldering temp or time (see a related thread on this in the last few weeks), but as you already accommodate no lead finishes [now known as lead free] it shouldn't make any practical difference. You will still need to audit your components of course, not just for the lead free construction, but for the temp withstand. Regards Mike Fenner Applications Engineer, European Operations Indium Corporation T: + 44 1908 580 400 M: + 44 7810 526 317 F: + 44 1908 580 411 E: [log in to unmask] W: www.indium.com Pb-free: www.Pb-Free.com -----Original Message----- From: TechNet [mailto:[log in to unmask]]On Behalf Of Ofer Cohen Sent: Thursday, May 29, 2003 4:06 PM To: [log in to unmask] Subject: [TN] Combination Leadless and SnPb Hi all, Lately I receive messages from components manufacturers, stating they are moving from Tin-Lead finish to lead-less finish (not specified which one - my regular question that regularly is not being answered). Most of the components are still with the SnPb finish, the PCBs Tg are 145 deg C, unless I had a specific need (extra depth, for instance to move to what is currently called high Tg (and in the future will probably be the standard boards) and the pastes are, of course, SnPb, hence would not survive the higher soldering temperature needed to tickle the lead-less finish. Should I modify the work processes? Should I wait? Are there any workmanship/ reliability effects to these changes? Helppppppppppp... Regards Ofer Cohen Quality Assurance Manager Seabridge Ltd. --------------------------------------------------- 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 ----------------------------------------------------- --------------------------------------------------- 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 -----------------------------------------------------