Sira, If your spec demands that you do not have solder balls, and you do ask how to remove them - try cleaning after soldering! I do not want to appear flippant, but if you are running no-clean with inert gas, then the propensity of solder balls generally increases. If the product is safety critical - clean it, it is usually cheaper and quicker. We have many customers who profess to run no-clean but who have many cleaners - to clean stencils, misprints and pallets and because they use a no clean flux/wire/paste, the cleaning bill is higher. Just some thoughts for consideration... Regards, Graham Naisbitt [log in to unmask] Concoat Limited Alasan House, Albany Park Phone +44 (0) 1276 691100 CAMBERLEY GU15 2PL UK Fax +44 (0) 1276 691227 -----Original Message----- From: Sira Rikulsurakan <[log in to unmask]> To: [log in to unmask] <[log in to unmask]> Date: 14 October 1998 22:01 Subject: [TN] No-Clean Solder Ball. >Dear Technetter. > We are facing Solder Ball problem for SMT No-Clean process. The >balls are always in contact with 0603 Chip capacitor and resistor and also >fixed by flux. Diameter of the balls is less than 5 mils. > Stencil thick is 6 mils. Stencil apertures of the 0603 component are >“ Home plate “ shapes. Solder paste thickness is about 7.4 mils. > We had extended “Preheat” portion of reflow profile to cure solder >paste and reduce peak temperature of “Reflow” portion to stop splash but >solder balls are still found after reflow. > Would anybody please suggest us how to eliminate the solder balls. >Thank you. >Mark. > >################################################################ >TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c >################################################################ >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's web site (http://www.ipc.org) "On-Line Services" section for additional information. >For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 >################################################################ > > ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ 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's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################