Something could have changed in the flex piece. Is there an adhesive bonding the copper to the dielectric? The thermal conditions could degrade it. The ductility of the copper can also change with heat. The differential thermal expansion between copper and organics can introduce stress. Look to a difference in the thermal profile between the two runs. J S Sallo Sallo Consulting Phone or Fax 619 346 6717 *************************************************************************** * 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. * ***************************************************************************