Hi, For quiet long I've heard people said that the reflow profile must be change for each board depending of the thermal mass of the board. My question is how do you calculate this Thermal mass? Or to have a good profile do you take all the datasheet of the component on the board and take an average of that? Hope you can help me with this issue. Thanks You Yannick Brisson ============================ Technicien SMT Technician SMT M2S Électronique 2855, Rue de Celles Québec, Québec G2C 1K7 Téléphone: (418) 842-1312 Ext: 264 Télécopie: (418) 842-0123 [log in to unmask] ============================ --------------------------------------------------- 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 -----------------------------------------------------