Nancy, IPC-TM-650 microsection methods 2.1.1, manual microsectioning is the one referenced in the 276 document. This doesn't have figures illustrating the exact measuring locations, however the 6.1 para addresses that thickness should not be determined at nodules , voids, cracks or irregular and thin platings. If your hole wall was very rough, you might have nodules where the plating was thicker than others and deep folds where the plating thinned. These would not be indicative of the actual deposit if the hole wall was not rough. The thin areas are considered ok, if they do not go below 0.0008". Hope this helps Susan Mansilla Robisan Laboratory 317-353-6249