In former incarnations, we always preheated the ceramic. I agree that you can get good solder joints without preheat, but it sure makes it much easier with the preheat. The problem I have seen is when you don't have the preheat, people feel under the gun and are forced to not do a good job (gotta ship and/or need to make my numbers). I strongly suggest that either keep the preheat or make it impossible to "cheat." ______________________________ Reply Separator _________________________________ Subject: Preheating of Ceramic Chip Capacitors Author: [log in to unmask] at Internet Date: 10/10/96 9:45 AM Dear Technet, We are a military assembly house that employs preheating plates for ceramic chip rework to reduce the risk of internal chip delamination from thermal shock. This has been done per IPC recommendations. However, this step in the rework process is time consuming and cumbersome. We have done minor and informal tests to determine the real value of this practice and found that it really is not needed if the operators take care in their soldering. If the tip size and heating time is controlled, there doesn't seem to be an immediate effect or a temperature cycling effect on the chips. I am interested to see how widespread the use of preheating plates actually is. I would like to hear from anyone having any experience indicating that the process is actually necessary. (or not necessary) Thank you in advance for any input. Jason Spera Manufacturing Engineering General Atronics Corporation *************************************************************************** * 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. * *************************************************************************** *************************************************************************** * 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. * ***************************************************************************