We currently have a board requirement for a 7 layer board. The design limits the modification to make it a balanced even numbered layup and to rearrange thicknesses. The cores are single sided cap with 3/8 oz. CU. .0039 core followed by .016 core 3/8 / 3/8 CU .016 core 3/8 / 3/8 CU .016 core 3/8 / 3/8 CU Question: Does anybody have any ideas to help reduce the warpage that will occur on this type of layup? ROR, Lagging, Cool Rates, etc..... thanks ################################################################ 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 ################################################################