Hello in there, No, you do not need to worry about losing bits off the bottom during second reflow. The surface tension of liquid solder is more than enough to keep little passives in place. All my boards have many, many passives underneath and a few IC's besides, and they all hang on there perfectly. Peter STAero ART HAMPTON <smt@Q-TRONIC To: [log in to unmask] S.NET> cc: (bcc: DUNCAN Peter/Asst Prin Engr/ST Sent by: Aero/ST Group) TechNet Subject: [TN] Bottom Side Reflow!! <[log in to unmask] ORG> 03/07/02 05:00 AM Please respond to "TechNet E-Mail Forum."; Please respond to ART HAMPTON Hello Out There, Recently I was assigned the task of creating profiles that would fall within the ( PWI ) for solder paste Kester ( 562 ) for processing pcbs with several (bga) components on the top side, however the bottom side of the pcb also has 1,200 placements of cap, and res. reflowed not epoxyed, do I need to be worried about losing my bottom side components? Art ____________________________________________________ (Embedded image moved to file: pic13944.gif) IncrediMail - Email has finally evolved - Click Here [This e-mail is confidential and may also be privileged. If you are not the intended recipient, please delete it and notify us immediately; you should not copy or use it for any purpose, nor disclose its contents to any other person. Thank you.] --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d 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 delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail 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 ---------------------------------------------------------------------------------