Julien, It is not clear whether your pick and place equipment works by moving the circuit pack on a dynamic x-y table or whether the pick and place heads do all the moving. If your system is the former, then why not program it so that your problem part is placed last so it is not subjected to any of the sudden stops and starts of the table? If the part is moving from just the normal forward movement of the conveyor belt and its attendant slow stops, then you have a more difficult problem to solve. One company I know of solved this sort of movement problem by getting its problem board made with Precision Pad Technology (PPT) and sticking the part down with a tack flux. The tack flux was sufficient to keep the part in place, unlike the solder paste on ordinary boards. regards, Bev Christian XLTEK -----Original Message----- From: Julien Bouchard [mailto:[log in to unmask]] Sent: Monday, September 11, 2000 11:04 AM To: [log in to unmask] Subject: [TN] Displacement of PQFP with heat slug Hi everybody, We currently have problems with some PQFP ( 208 and 240 pins ) that have a piece of metal mold inside the IC to enhance the thermal exchange. Because of this metal, the IC is very heavy, in comparaison of other IC. After they have been place by the pick and place machine, they often move from there original position when the conveyor start or stop. It seem that the IC is so heavy, and is inertia is taller than the retention force of the paste. We try a lot of solution, but none of them give a good and constant result. We want to know if someone have similar problem and if a good solutions have been found. Thank you. Julien Bouchard Matrox - Process Engineer Email : [log in to unmask] ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8d ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - 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 1.8d ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ##############################################################