I am trying to decide how to go about defining pads and traces so that I may extract photoplot files for pcbs from the drawing. so far for pads I have come up with a nested block the main block is defined as DXXX for the aperture name and the aperture description for the nested block such as D10 for the block name and ADD10C_.055 for the name of the nested block. the graphic in the nested block is the whatever you want it to look like on your drawing. the description for the drill blocks would be TXXX and the name of the nested block would be the diameter of the hole in whatever format you want for the Excellon file. traces and silkscreen graphics would be extracted from the entities section from plines or from the layer name. if I use plines then the data for all of the files would be available in one dxf file. then I could use the layer names to define the names of the Gerber and Excellon files. Any other ideas or links to relevant information. How I structure the Autocad dwg file determines how I have to write the conversion software.
Bob