And a happy holiday season to you Bill. Wouldn't it be better talking holiday cheer than of warped PCB's, though it's one of my favorite things. What are some others? Definitely love the smell eminating from a hot lamination press wherein epoxy, or my particular favorite - polyimide, is burning and turning out flat, or not, MLB's. It's even better when given the opportunity to help fix a problem or two associated with it. As you already know, if it ain't the design, it has to be the fab process or what goes into it - right or wrong. Materials, constructions, press condition, press cycles and some more interesting things make flat boards when carefully selected and managed. I suggest having a friendly visit with your supplier, say over some very highly laced egg nog, and discuss world conditions and those of the processes inside as well as those out when materials are brought up. It's really just too easy to make flat boards. Truth is, it's hard not to make them that way. Again, seasons best and sleep on the issue for a while because sleeping on the boards will not make them flat. MoonMan --------------------------------------------------------------------------------- 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 ---------------------------------------------------------------------------------