Depending on your oven you can generate enough delta t to do this sort of thing simply by placing boards too close together. You need enough time and temperature over liquidus to allow the solder to flow and wet, before the solder melts you need a profile that will deoxidise the oxide free powder to allow it to coalesce and still retain enough activity to help the above spread and wetting. Getting this bit wrong can produce the familiar (to some) it hasn't melted syndrome. When profiling therefore it is a good idea, if you didn't, to run some loaded boards (don't have to be functional) ahead of the thermo coupled one to simulate a loaded oven. 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 Black, Paul Sent: Friday, August 22, 2003 1:10 PM To: [log in to unmask] Subject: Re: [TN] Soft solder Thanks for the advice, Werner. I didn't realize this document existed. The original recipe was determined by running a thermocoupled assembly through the oven and matching the time/temperature graph supplied by the paste manufacturer. When the manufacturer made adjustments to the recipe, it was done with the aid of a Super MOLE. Thank you, Paul Black Manufacturing Engineer Kronos -----Original Message----- From: [log in to unmask] [mailto:[log in to unmask]] Sent: Friday, August 22, 2003 7:49 AM To: [log in to unmask]; [log in to unmask] Subject: Re: [TN] Soft solder Hi Paul, Are you profiling your assemblies to determine a proper oven recipe? Look ay IPC-7530. Just calling in your paste supplier is in many cases not sufficient. Regards, Werner Engelmaier Engelmaier Associates, L.C. Electronic Packaging, Interconnection and Reliability Consulting 7 Jasmine Run Ormond Beach, FL 32174 USA Phone: 386-437-8747, Fax: 386-437-8737, Cell: 386-316-5904 E-mail: [log in to unmask], Website: www.engelmaier.com --------------------------------------------------- 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ----------------------------------------------------- ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: This email, its content and any files transmitted with it are intended solely for the addressee(s) and may be legally privileged and/or confidential. If you are not the intended recipient please delete and contact the sender by return and delete the material from any computer. Any review, retransmission, dissemination or other use of, or taking of any action in reliance upon, this information by persons or entities other than the intended recipient is prohibited. Messages sent via this medium may be subject to delays, non-delivery and unauthorized alteration. This email has been prepared using information believed by the author to be reliable and accurate, but Indium Corporation makes no warranty as to accuracy or completeness. In particular, Indium Corporation does not accept responsibility for changes made to this email after it was sent. Any opinions or recommendations expressed herein are solely those of the author. They may be subject to change without notice. ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: --------------------------------------------------- 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/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 -----------------------------------------------------