I thought I would bring up another consideration in this discussion -- resource management. Is it better to leave the copper pads on the circuit board, or etch it off into the etchant? From the perspective of raw material usage, it seems to me that it would be better to leave the pads on, then, less resources, etchant-wise, are needed to remove those pads. Also, looking at the life cycle of a printed circuit, that copper would then be recycled or reclaimed in the same manner as the rest of the circuit. Here again, my gut feel is that this would consume less resources than etching off the pads. This is assuming standard processes are used -- namely subtractive; although there may be considerations for semi- or fully-additive technologies. Robert Lundquist Assistant Director -- MnTAP Suite 207 1313 Fifth St. SE Minneapolis, MN 55414 612-627-4557 612-627-4769 FAX [log in to unmask]