> 1. Some portions of the PCB library have values associated with > footprints, e.g. "1M" resistors and "100K" resistors, etc. I thought > this was unnecessary. Or maybe I'm missing some vital point... > you can tell me about it.
Before gEDA, pcb was used stand-alone. In that mode, it made sense to have one footprint for each part you have in inventory, not just for generic parts. The m4-based library and the table of contents made supporting this pretty trivial. > 4. I did not understand the rationale for the drill dias of the pads > in some of the parts in the PCB database. I have tried to select > the drill dia carefully here, based on my limited knowledge of > the lead diameters. Different people designed the symbols around different sample parts. > 5. In my hobby electronics experience, I find that the annular > copper ring around a drill hole for a pad needs to be at least > 10 mil in width, preferably 15mil, YMMV. I prefer 6-8 mil unless the hole is structural (mounting screws, terminal blocks). > But with this brilliant decision of PCB to keep all file formats > as ASCII, it'll be easy for someone to write a script to patch > the pin annular widths as per your preferences if you wish. (I > would love to have a script which can do with a PCB layout what > Eagle does in its DRC: set a min width and max width for annular > rings, with a percentage of drill dia as the guiding rule for > in-betweens.) Write one. The plugin system makes this pretty easy. > 8. I wanted elongated pins/pads for some of the higher-current > devices. So I incorporated them. I don't know whether it'll > work in reality when I include the device in PCB. I haven't yet > generated Gerbers and checked. Should, if the pads and pins have the same number. _______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
