Are these caps on the topside or bottom side going through the wave? >>> "Kane, Joseph" <[log in to unmask]> 05/14/98 10:33am >>> We are experiencing failures of .25% film capacitors, presumably from heat damage during wave solder. Top side preheat temperatures measured 210F, within the process range we like. Tried cooling it down to 163F topside, got more solder defects, and some caps still going out of tolerance. We suspect that parts can't take thermal transfer during transit through the wave, where topside gets about 100F warmer (of course part bodies see less). Manufacturer says no, it's our preheat, still too high at 163F, even though they claim that the film can withstand 284F in the preheat zone. Boards are at least 10 layers with planes, and soldering cooler than 163 will mean lots of defects, especially where the RMA doesn't dry out or activate properly. Speeding up the conveyor results in lots of top side insufficients. Hand soldering works, but is expensive. Can't live with these parts, can't flush them. Should we consider cooler preheat, or are there other wave solder tricks we can try? Joe Kane Lockheed Martin Control Systems ################################################################ 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 web site (http://jefry.ipc.org/forum.htm) for additional information. For the technical support contact Dmitriy Sklyar at [log in to unmask] or 847-509-9700 ext.311 ################################################################ ################################################################ 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 web site (http://jefry.ipc.org/forum.htm) for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################