It's Monday morning and my head is....etc. I'm cleaning my TechNet mails a number of months back. Found a mail from Fluke that is possibly of interest for warpagers. I got this from Fluke just when we had a w. problem, and Fluke's advice came in right time. Of course, not a general problem solver equation, anyway, hope it adds something to someone. Regards Ingemar Hernefjord Ericsson Microwave Systems DEWARP PROCEDURE De-warping shall be accomplished using the Press Area oven as the primary tool. If it is unavailable, the Screening Area oven may be used as a backup. All de-warping must be coordinated with the Press Area operators to ensure that press schedule is not compromised. If there is a conflict of order priority, the final decision will be made by the Process Owner. STACKUP PANELS Place the Oven Shelves no lower than the 4th slot from the bottom to prevent them from coming too close to the heating elements. Stack panels to be de-warped (maximum 4 high), using the following configuration. DO NOT PLACE ANY WEIGHT ON TOP OF STACK! BAKE THE STACKUP If using Press Area oven, preheat to 325°F. If using Screening Area oven, preheat and verify oven setting of 300°F. Place stack-up inside preheated oven. Bake for (4) hours. After (4) hours, shut down oven. Allow panels to cool slowly inside oven with doors closed, to below 120°F. before removing them from the oven. IT IS EXTREMELY IMPORTANT THAT PANELS COOL SLOWLY! Remove panels from oven. RE-MEASURE FOR BOW AND TWIST Re-measure for Bow and Twist using the criteria in the previous instructions. Fill out a Discrepancy Report to MRB any panels that do not meet the bow and twist criteria. Complete the Log Sheet and indicate how many panels were MRB (scrapped) AFTER de-warping. MARKING DEWARPED PANELS THAT HAVE MET THE CRITERIA Using an electric engraver, scribe a ¼" letter "W" within a ½ inch of one of the auto-insertion holes (not slots) on the carrier frame. Mark the letter "W: on the Circuit 1 side only. Do not make any marks on the actual PCB (part). Mark the carriers, only. Fred J. Paul, Staff Engineer, PCB Operations FLUKE Corporation, P.O. Box 9090, Everett, WA 98206 VOICE: 425 356 5734 FAX: 425 356 6070, [log in to unmask] ############################################################## TechNet Mail List 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://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Gayatri Sardeshpande at [log in to unmask] or 847-509-9700 ext.5365 ##############################################################