I have an upcoming high volume product that requires a very tight tolerance on the bare PCB. I need to locate the center of 3 non-plated holes of 2mm diameter to +/- .004" X/Y tolerance to an etched feature. The etched feature is square and is on one of the outside layers of the board. These holes are used to mechanically align a component to copper features on the board. Improper alignment will result in massive shorts or opens. My questions are as follows: 1. For standard processing what tolerances are typical for NPTH to etch feature registration on a PCB. My experience is that it is somewhat greater than +/-.004" for standard processing. 2. Is there special automated equipment (or a process technique) that is available for high volume production (i.e. more than 10K per month) that can improve this tolerance? For example I have heard of optical drilling equipment that can drill a hole with great precision relative to an etch feature, much like a pick and place machine locates a SMT part to a fidicual. I've "heard" of it, but never seen it or talked to equipment manufacturers. 3. Is there any equipment out there that can measure this dimension? (i.e. the center of a non-plated hole to the center of a square copper pad). I'd appreciate any insights or comments. [log in to unmask]