We used to heat soak assemblies to be reworked for 2 hours at 90 deg C in a calibrated oven, and re-heat them for half an hour after approx every 10 minutes of rework (if they took that long). Typically-used temperature ramp rate for PCA's is 5 deg C/minute. If you want to fine-tune the soak period to reduce the time in the oven, stick a couple of thermocouples on the board attached to a data logger, and see how long it takes for the board to reach the soak temperature. Peter Duncan "Rougeux, Scott" <Scott.Rougeux@P To: [log in to unmask] LEXUS.COM> cc: (bcc: DUNCAN Peter/Asst Prin Engr/ST Sent by: TechNet Aero/ST Group) <[log in to unmask] Subject: [TN] FW: preheating assemblies prior > to rework 09/27/01 03:21 AM Please respond to "TechNet E-Mail Forum." > Your input is requested on this issue. > In regards to preheating assemblies prior to reworking them on the Solder > Fountain/solderpot. > We have been asked to look into preheating components or boards during > rework. This opens many questions: > * What is the desirable preheat temperature? > * How is it measured? > * Where is it measured? > * How quickly can the assembly be heated? > Thanks. > --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 --------------------------------------------------------------------------------- [This e-mail is confidential and may also be privileged. If you are not the intended recipient, please delete it and notify us immediately; you should not copy or use it for any purpose, nor disclose its contents to any other person. Thank you.] --------------------------------------------------------------------------------- Technet Mail List provided as a free service by IPC using LISTSERV 1.8d To unsubscribe, send a message to [log in to unmask] with following text in the BODY (NOT the subject field): SIGNOFF Technet To temporarily halt delivery of Technet send the following message: SET Technet NOMAIL Search previous postings at: www.ipc.org > On-Line Resources & Databases > E-mail Archives Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ---------------------------------------------------------------------------------