I agree with the point raised about pre heating during rework and repair of ceramic capacitors. In the good old days the problem with these parts was a real issue. I have always evaluated ranges of parts for production buy immersing the parts in a solder bath without preheat for process compatibility as suggested in the IEC test method. This sorts out the men from the boys. All other guidelines for wave and reflow are still relevant but preheating of parts ????? When originally asked to comments on the IPC video tape on rework, which I guess this comes from, where the pre heating on a hot plate was suggested I stated that it did not happen in the real world. Cracking to day in parts is mainly seen as a result of flexture failure of parts. If they crack during soldering it is more likely to be a result of questionable parts. Bob Willis Process Engineering Consultant Electronic Presentation Services 2 Fourth Avenue, Chelmsford, Essex CM1 4HA. England. Tel: (44) 01245 351502 Fax: (44) 01245 496123 Home Page: http://ourworld.compuserve.com/homepages/Bwillis Email: [log in to unmask] *************************************************************************** * TechNet mail list is provided as a service by IPC using SmartList v3.05 * *************************************************************************** * To unsubscribe from this list at any time, send a message to: * * [log in to unmask] with <subject: unsubscribe> and no text. * ***************************************************************************