Kerry - the Tg is only a very small part of the equation, T288 and Td are more critical parameters. If you attempt to run a T288 on 406 it blows up before it even reaches the Isotherm. If you run a T260 it might survive 2 to 4 minutes - not a lot of thermal fudge factor given the possibility of multiple reflows and reworks. Isola, who manufactures the 406 does NOT recommend this material for 260C reflow situations and have introduced the 410 as it's replacement. At Photocircuits Corporation, we are recommending to our customers of either 406 or PCL370 to switch to IS410 or PCL370HR respectively. As the old saying goes - you can make one of anything but for a reliable material in the lead free assembly world forget the 406. Gerard O'Brien Dir. Of Material Test, Reliability and Technology -----Original Message----- From: Kerry McMullen [mailto:[log in to unmask]] Sent: Wednesday, May 11, 2005 12:03 PM To: [log in to unmask] Subject: [TN] FR406 Tg 175 Degrees C - Lead Free Processing Hi TechNetters Can I use FR406 175 Degrees C laminate during a lead free assembly process where the reflow temp will be around 260 Degrees C. ? The boards will be ENIG. Any disadvantages. I know there was a thread, but I can't find it. --------------------------------------------------- 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 847-615-7100 ext.2815 ----------------------------------------------------- --------------------------------------------------- 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 847-615-7100 ext.2815 -----------------------------------------------------