Al-- I beleive that you may be in violation of MIL-STD-275E section 5.6.4 depending on you plating requirements. Along with that, it is also important to consider the physical location of the pwb with respect to the end product - is the chassis, casting, etc in physical contact with the the plane, and is there any electrical problems??? IMOA, cut the plane back from the edge of the board-- end of story!! Bob Vanech [log in to unmask]